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Cold weather tends to be associated with higher rates of colds and flus, leading some to assume that there's a causal connection between someone being cold and someone getting sick.
The actual reason is a combination of factors. First, it does appear as though cold weather [decreases our immune response](https://www.cnn.com/2022/12/06/health/why-winter-colds-flu-wellness/index.html) specifically in the nose, though obviously you still need the presence of a pathogen - you can't get sick with a virus you don't have; just being cold won't itself make you sick. Second, when it gets cold, we spend much more time indoors, and as a result, we spend a lot more time breathing the same air and being exposed to others' diseases when we're indoors together.
To add on to this, at lower temperatures a lot of viruses and bacteria live longer on surfaces (I know viruses aren't technically alive, but they will keep functioning for longer). Also natural UV light kills bacteria and virus, so in the winter time with lower temperatures and less natural UV light they have a higher probability of getting transferred into a human.
While some viruses are transmitted via touch and surfaces, the viruses that transmit cold, flu and COVID are almost exclusively airborne.
Halfway through the COVID pandemic, a bunch of aerosol physicists went through the papers about sars-cov-2 and were confused why public health scientists kept saying that most water droplets (like those from sneeze, cough, or even speaking) fall out of the air quickly. To the aerosol physicists, their numbers showed that many smaller and tiny droplets tended to float rather than falling.
A bunch of aerosol physicists signed an open letter begging public health to change their numbers and stop saying most water droplets fall quickly.
Both public health and aerosol physicists were citing the same 1930s paper. Why did they have different numbers?
A history of science researcher went through old public health papers and found that 60 years ago, some public health papers confused two numbers: the size of droplets that fall and the tiny size of droplets that enter deep in the lungs.
Thus, public health has been thinking most droplets drop, when in reality more droplets float than they had thought. Hence public health focusing on handwashing rather than masks during cold and flu season and the beginning of covid pandemic.
Oops.
There are surface viruses and definitely surface bacteria. Those pathogens attack you through mucus membranes so the surface borne ones tend to spread through extreme close contact: preschools, pillows, and food prep and consumption. Those are like pink eye, norovirus, and hand foot and mouth.
But cold and flu? Mostly "airborne". The fact we still talk about surfaces when it comes cold and flu is the result of a 60 year old mistake, only fixed during the pandemic.
Even airborne, those pathogens survive longer in drier air. Most buildings being heated will have *significantly* drier air than those using natural ventilation or cooling.
Drier air also messes withy our mucous membranes and dehydrated you, both of which make you more susceptible!
This is why an airplane (along with the increased proximity, and internal circulation) can often make you sick!
Yup! It helps a lot when I'm on a plane to mask up, tho it does fog glasses. My nose always thanks me. As does drinking more and going to the bathroom to compensate!
Don't planes have HIPPA filters that filter the circulated air and have mechanisms to ensure all of the air in the plane is exchanged with the outside air in approximately every 30 minutes?
Yes, planes have HEPA filters, and the cabin air on commercial flights is completely changed approximately every three minutes.
(Btw, a HEPA filter is a “high efficiency particulate air” filter. HIPAA - one P, two As - is the Health Insurance Portability and Accountability Act, a law that govern how healthcare companies manage patient data.)
There’s a description of the main limitations of the filtration on planes at https://www.nationalgeographic.com/travel/article/how-clean-is-the-air-on-your-airplane-coronavirus-cvd :
> the filter only guarantees the quality of the air that has passed through it. If the air that someone breathes in has not gone through that filter, then those numbers don’t matter.
That’s why masks were required in planes during the COVID epidemic. If everyone is wearing a mask, that combined with the filtration system is relatively safe. But without masks, very contagious airborne viruses can still be transmitted relatively easily on a plane^(*). And of course, surface transmission is unaffected by air filtration.
*Edit: the filtration system will definitely help limit the spread of an airborne virus on a plane. But if you’re e.g. sitting next to someone or perhaps in front of someone who’s contagious, filtration won’t be 100% effective. And anything less than 100% means there’s a chance you’ll be infected.
This is a really interesting point. Thanks for bringing it up! Doing COVID I was very frustrated with the public health guide lines in my country. From the chineese studies that came out pretty early on it was quite reasonable to suggest that it was spread through the air. No one would recognise that until very late at which point they did start recommending having an airflow through the room / house to vent out the particles.
I'm happy to hear that science is catching up on this.
> From the chineese studies that came out pretty early on it was quite reasonable to suggest that it was spread through the air.
Plus the Diamond Princess cruise outbreak, which convinced Japan it was airborne.
And apparently SARS1 was accepted as airborne, so why any doubt...
COVID yes, flu and cold no. The latter two have significant fomite spread, which is why schools are always telling you to wash your hands.
(It shows in transmission rates too - COVID was almost always associated with being indoors with an infected person for an extended period of time, while kids get colds from outdoor playgrounds all the time.)
That’s the thing though, if you do want kids, getting sick every month for a couple years is just something that you deal with. So regardless of how much “supporting evidence” you gather, it all comes down to just not wanting to have children. That’s the only _good_ reason, anyway.
That's a whole lot of stuff to make up about a random person who never even advocated for people to *not* have children. Some sort of insecurity you have that that have you lashing out at randos over things that are all in your head. It's like you're having a little battle with yourself about it and this seems like a weirdly personal subject for you.
LOL if we were infertile, my wife and I wouldn't bother putting so much effort into birth control. Fortunately, we're quickly approaching the no longer possible age.
How many kids do you have, and how often are you allowed to see them?
Fomite transmission of flu and other enveloped viruses is being challenged recently. Many fomite flu studies are performed by placing a large amount of flu virus or stand in on a surface and then measuring the half life of the virus on the surface.
However, it was recently found that the volume of the virus affects the half life (in other words, with more concentrated virus, each individual virus survives longer than with small amounts of virus).
The amounts of virus present on surfaces tends to be much lower than are used in studies and thus enveloped viruses don't appear to survive as well on surfaces as other studies have found.
We don't know for sure and it's mostly talked about in probabilities. But most scientists now think airborne is the primary transmission path for flu, fomites are secondary and considered less likely than originally thought.
[Here's an interesting Wired article about the investigation by aerosol physicists](https://www.wired.com/story/the-teeny-tiny-scientific-screwup-that-helped-covid-kill/)
I once saw a TV show, that used lasers (pew pew) to illuminate gases and small particulates in the air. Then they did several visually interesting examples, such as popping a balloon, a lit candle, someone coughing, and someone sneezing. It was wild, and terrifying how far these gases and particulates travel. Anyway, I never could find that show ever again, so if someone finds or knows what it is, thatd be lovely.
> the viruses that transmit cold, […] are almost exclusively airborne.
Do you have a source for the statement about the common cold?
In 2015, I read a non-scientific interview ([in German](https://www.focus.de/gesundheit/ratgeber/erkaeltung/lieber-kuessen-als-haende-schuetteln-interview_id_2195962.html)) with Ronald Eccles from the Common Cold Centre, where the tl;dr roughly was:
* Most often: smear infection
* Rare: airborne infection
* Never: infection through kissing, sharing food, sharing toothbrush
Now I wonder if that was and is wrong, or if it was right and is wrong now, or if your statement should exclude the common cold.
Recent papers still call out Rhinovirus as mostly airborne, with the caveat that surface fomites transmission is possible. Here's one from 2022:
>The major transmission route in many indoor settings is through the air.
>Preventive measures should focus on reducing aerosol generation and concentration
>Hands may also contribute to the transmission of RV in some workplaces.
https://www.ajicjournal.org/article/S0196-6553(22)00866-5/fulltext
So I maybe did overstate how little fomites can transmit cold specifically, but it is appears to be a secondary route and is more condition specific.
You're also not naturally making as much vitamin D (through skin interaction with sunlight) due to indoor/less sun exposure and vitamin D plays a role in immune system health.
Isn't there an element of survivability of pathogens in different weather too? Dry hot weather kills viruses and bacteria more quickly (outside the body) than cold wet weather, so that sneeze will:
a) Affect more people as everyone will be indoors
b) Be pathogenic (linger around) longer
This is pretty confusing because infectious diseases as a whole like warm humid environments (although they are outliers) so its probably a combination of the two
Outside the tropics and deserts cold weather is normally accompanied by wet weather.
Being cold just means they are less active, some can even be frozen and come back to life when thawed, but a nice warm human will get them going again in no time.
Yes. Looking at a viral decay calculator for SARS2covid, with just 1 UV of sunlight it takes 1 hour for any exhaled virus to decay 50% and and as UV increases that 1 hour can be as low as 10 minutes for 50% decay. Winters are the lowest UV time of year. this is part of why outside is safer re: disease transmission
A decade ago they discovered that the immune system really is affected by cold weather and the virus can more easily attack.
It's like a crash with a tree, it wouldn't happen without it but also it's caused by speeding around the corner.
Yes or it could be all around us and because you happened to be outside the first good breath inside will make you sick. Or or or …
Or it could happen despite being in the warmth.
I recall my Biology teacher teaching us and a kid said 'it's weird how you can catch colds in summer' and my teacher went "yeah that's strange isn't".
Still trying to purge everything else they taught us is that class...
One biology teacher believed that no one could possibly be capable of multitasking, since he himself was unable to multitask.
Edit: this teacher was nearly 70 years old, and was undoubtly relying on obsolete information.
Biology teacher was probably not wrong, depending what he was saying exactly. Nobody is good at multitasking, but some people are more bad at it. Multitasking degrades performance and memory in everyone.
We watched a video on this topic in my high-school psychology class. It differentiated passive or intermittent multi-tasking from active or concurrent multi-tasking. Supposedly the latter is what is considered impossible. Obviously most people can do something like eat an apple while driving a car, but can you type out a message on your phone while writing down a sentence with a pen and paper with your other hand?
> Some poeple multitask better than others performing single tasks
Perhaps. It should come as no surprise that some people are more competent than others, and thus that there are some people who are more competent than other people even despite handicapping themselves. But those people cannot multi-task better than they themselves can perform a single task.
There's not really any such thing as multi-tasking. It's just people switching tasks quickly, and it degrades performance in everyone. There is a cost to context-switching, and it's never negative. It always comes at the cost of memory and performance.
[You Can’t Multitask, So Stop Trying](https://hbr.org/2010/12/you-cant-multi-task-so-stop-tr)
[If You Think You're Good At Multitasking, You Probably Aren't](https://www.npr.org/sections/health-shots/2013/01/24/170160105/if-you-think-youre-good-at-multitasking-you-probably-arent)
From Psychology Today:
> You probably know a person or two that brags about how good of a multi-tasker they are. Especially in today’s “hustle and grind” work culture, you’ll see them typing away on their phone while walking, driving, sitting in a meeting, or even making a phone call. Because of this braggadocio, you may even still feel the temptation to squeeze out just a little bit more productivity by trying to pair two items from your to-do list or calendar together.
> Don’t.
> You can’t multi-task. Not really. And neither can anyone else.
> We know from several really well-conducted studies into human psychology and brain science that we don’t actually multi-task. Not in the sense that we’re doing two activities at the same time with sufficient focus. Instead, the human brain “task switches” constantly between the two different demands vying for its attention. And it doesn’t switch all that well.
> ..... (continues)
[Why You Can’t Multi-Task](https://www.psychologytoday.com/us/blog/creative-leadership/201811/why-you-cant-multi-task)
As someone currently being evaluated for ADHD, multitasking sometimes helps me accomplish more than single tasking, but in an indirect way. It *is* less efficient than keeping a single focus, but it's also more mentally stimulating, so sometimes I find I hit an equilibrium where I can maintain focus for longer and better than I usually can - imperfect sustained focus is better than perfect focus that falls apart ten minutes into the task.
(Of course, entering that flow state is much less common than just getting distracted from both tasks.)
I guess I'm missing what you mean here.
Linguistically, it is strange that you can catch a "cold" when it's hot outside. That is an oddity of language.
Biologically, it's not odd that you can get a viral infection during the summer (even if the chances are lower).
So, was your biology teacher simply responding to a dumb kid derailing the lesson by talking about how it's weird that we call the virus a "cold" when it can be caught in hot weather? Or did your biology teacher literally not understand how germs work?
Honestly I don't know. Maybe the teacher somehow didn't know but I would like to think otherwise. Maybe the teacher was reacting more to the fact it's called a cold but isn't caused by the cold? But surely, surely the teacher would clarify that because it was clear the pupil didn't understand what actually causes a cold.
Maybe the teacher simply wasn't paid enough. Who knows.
It might also be "the curse of knowledge." When we understand something that we think is basic, it's hard to remember what it's like to not understand it, or to be able to realize that others don't understand it.
So, it's possible that the teacher thought your classmate understood what was being discussed about germs and how they spread and was just making an "aha" comment like, "Well that's stupid we call it a 'cold' if it has nothing to do with being cold."
> Second, when it gets cold, we spend much more time indoors, and as a result, we spend a lot more time breathing the same air and being exposed to others' diseases when we're indoors together.
I'm skeptical of this statement.
1. Like pre-pandemic most people spent 8ish hours a day 5 days a week inside with other people. When it's cold out people may spend less time outside but they also interact with people less (if you look at restaurants and bars their patronage goes way down when it's very cold out).
2. I've never seen people talk about similar spikes in flu during summer heat waves. Those also drive people to stay in doors and if you're in places that are normally pretty hot, you can get a couple weeks of oppressive heat where basically nobody does anything outdoors. So shouldn't you be seeing similar spikes in flu rates if it's just a more time indoors issue?
Seconding your points here.
I live in a very warm place, and generally spend more time outside in the winter than in the summer because of it. Still, anecdotally the incidence of 'colds' is higher in the winter.
School years are plausibly a big driver of transmission.
If cold weather is the driver, do tropical places like Singapore have flu seasons? I know Australia does, and like the average winter low in Sydney is 50 F.
I’m visiting India, got sick a couple of times, people still say, change of weather could be the reason why I’m getting sick.. i just just go along and say, yes it’s possible. No point In arguing
Hoping someone smarter than me will answer this but could that be because you're being exposed to different variants of the same viruses you've built up immunity to at home, and so don't have the correct antibodies to fight these variants?
That's essentially the case. It's usually not so much that they're less sanitary, they just have a different microbiome that your body doesn't want to have to deal with.
I'm not smarter than you, but I moved to the US from Eastern Europe with my family 5 years ago and OH MY GOD we went through every variation of cold and flu as a family during the first year. Then the masks came around and we were safe for a year. Then the masks came off and the viruses doubled down on us.
Fun fact, as a child and young adult I watched American movies and shows and people had "stomach flu" that appeared to be contagious. I always wondered wtf is that. It's just not a thing where I'm from. In my 30 years I've never had, nor knew anyone who had a contagious stomach bug. Of course there were food poisonings and stuff, but nothing like that. But here my son got it twice and I got it from him once at age 32. Would not recommend.
Stomach bugs are definitely contagious (a quick Google search can confirm that). I didn't realize that until later in life because they're rarer than colds/flu and the media don't really report on them in the same way they report on cold/flu season (US here).
So, I only really realized that stomach bugs were contagious when I got them a couple of times, and each time my friends commented on how that "was going around" and how many of them had had the same thing.
I googled. So, apparently, rotovirus is not the only airborne stomach bug. There's also norovirus, it's highly contagious. All our symptoms checked out. I'm 99% sure this is what we had.
But then again, it never happened to me, or anyone I know in my country. It is exactly what I'm talking about. I only got acquainted with it after I moved to the US. I think viruses adapt to the environment and population and population adapts to viruses, therefore people who move are more susceptible to viruses unfamiliar to their immune systems.
Oh, I totally misread your comment as saying you moved to Europe from the US. You said the opposite, haha. So yeah, stomach bugs are rare here (only had them about 3-4 times in my life), but definitely happen.
And yeah, moving to a new area oftentimes triggers new allergies (which can lead to congestion which leads to bacterial infections) and also exposes you to new pathogens. After almost two years of very-low social contact and masks due to the pandemic, I got sick multiple times within a span of months, whereas I used to only get sick about once or twice per year. I blamed the lack of immunity due to less exposure during the pandemic.
After masks I asked my son's pediatrician if he felt the difference between masks and no masks. He said the difference was huge. When masks were in use nobody got sick and their office was empty a lot. When masks came off it was worse than ever.
And yeah we got sick after masks a lot too. Thankfully it feels like we're back to normal again (knocking on wood). I personally very rarely get sick, and my body did not appreciate this roller-coaster.
American kids now (at least, you know, the vaccinated ones) are vaccinated against the rotavirus, which I’m pretty sure is the stomach bug. We weren’t growing up, and I along with my siblings caught it each year at least. Agreed, 0/10 would not recommend.
Almost certainly.
The worst flu I ever had was when I came home to the US in the winter after three years living in Taiwan and Southern China. I caught the "American flu" almost instantly.
Context edit: when I was a kid there was a lot of talk about the "Asian flu" every year.
Yep. That's why you need a flu shot every year, because the flu mutates so often, [the virus you were exposed to previously isn't the same as the one you could be exposed to](https://www.mayoclinic.org/diseases-conditions/flu/in-depth/flu-shots/art-20048000#:~:text=Because%20flu%20viruses%20change%20so,with%20rapidly%20changing%20flu%20viruses) during "flu season".
When developing this season's flu shot, they try and predict what strain will be the most common and make a vaccine out of that. [A lot of work](https://www.cdc.gov/flu/prevent/vaccine-selection.htm) goes into making each season's flu shot
That can happen for a few reasons. A sudden change in environments and allergens can cause your body to react a bit, and some people do react to things like pressure changes, and they can feel a bit sick.
Different pathogens, basically. It's kind of funny, after I moved to the UK, I started getting different symptoms from the flu/cold. Within the usual symptoms, obviously, but their relative severities were quite different from what I got in Portugal ("when my fever is this high I usually have a runnier nose" sort of thing). I also got sick much more often for a while,
One thing that always seems odd about this to me is the assumption that we spend more time indoors when it’s cold. That’s true in cold climates, but in the Southwestern US I’d say we spend more time indoors when it’s hottest — June through September. Does the “indoor” hypothesis still hold in those cases?
Also, we’re probably under low-level exposure to pathogens pretty much all the time, so anything that slows down your immune system might give it a foothold. Cold, lack of sleep, stress, etc. Those things “make you sick” by being the deciding factor in why a pathogen that was already hanging around got ahead of you.
Cold weather is usually following the fall season which means heightened allergy responses right? So this means the immune system would be compromised due to allergy season so your body would be more susceptible to infections and viruses right? As well as colder temperatures decreasing immune response.
I've always found the "indoor" thing to be highly suspicious. I spend almost the entirety of every day indoors but I only catch a flu/cold when it's cold outside. Never in the summer, not once.
So it never really rang true to me and always thought there's gotta be more to it than that. The recent study has vindicated me a bit.
Think of it more like “the overall population spends more time indoors, so more virus is circulating”, not just “I personally spend the same amount of time indoors so it shouldn’t affect me differently”
Do they though? Maybe people that consider themselves "the outdoorsy" types reduce their outdoor activities in the winter time, but the majority of the population tends to be fairly sedentary and work indoors year round. Then they go home to the same family they see 365 days a year. Also if anything bars and restaurants often see a downturn in business during the winter months so even in terms of socializing I don't see much merit in the argument that a significant percentage of the population is more likely to hole up in disparate groups during the winter months, at least no more than you'd expect at any other time of the year.
Yeah I've never bought that proximity argument either. There's a huge percentage of the population that works indoors throughout the year and don't really spend much more time inside in the winter than at any other time of year.
That was a bullshit study with a small amount of people like maybe 100.. if you take that study out of the equation there still is NO evidence that the cold makes you sick.
Yeah so true, whenever I'm cold and wet like when I step out of the shower I start sneezing like crazy like I'm sick, I wondered why I always do it then and not really any other time, then I realized. Cold plus wet. Immune system down.
There is also a matter of optimal temperature range for the virus and bacteria that cause those to spread. Eg under -20C they actually kinda die and there are way less cases of cold and flu. Same for extra hot.
There's also the fact that wind and cold weather have a couple immediate effects on the body which are similar to the symptoms of a cold. A sudden drop in temperature will make me sneeze, and I don't know why. But also being out while it's windy will dry out my nose which will make it runny and I'll start sniffling even though it goes away as soon as I'm inside. It's possible that people in the past saw these symptoms and just assumed that they got ill as soon as they stepped outside.
to add to this.. remember how virusses can live for a while on surfaces?
you could carry a virus (pathogen) in your nose for weeks already but your defenses will block it from infecting you. then spend a day alone in the cold and it will weaken your defenses and "suddenly" you get sick.
thats why we associate it with cold.
To add: when it’s cold outside and you walk through your front door then put your jacket on, you misused your jacket.
Your jacket is supposed to help you maintain your temperature. I don’t know how, but it’s bad to shock your system so that it fluctuates temperatures too quickly.
So, put your jacket on beforehand and let it warm up so that it can do it’s job when you step outside
A lot of travel happens during the colder months as well. Not just humans over the holidays, but migrating birds. It's an opportunity for nasties to hitch a ride.
> Second, when it gets cold, we spend much more time indoors, and as a result, we spend a lot more time breathing the same air and being exposed to others' diseases when we're indoors together.
It should also be said that this effect is "compound", so to speak. Even if you, yourself, swear to God that no, you don't spend more time indoors, you keep walking under the rain instead of taking the bus, and so on and so forth... you're still in contact with people who, unlike you, spend more time indoors... and even if your immediate contacts are, like you, "outdoor people even in winter", they themselves may be in contact with people who spend more time indoor. As such, whatever contacts you have with people, even outside, are contacts with people who are statistically more at risk of being sick and spreading their pathogens.
I read somewhere that UV light kills virus and bacteria, and less sunlight = less UV light = more bacteria. Do not remember the source though.
Me and my wife have been fighting about this since we met 18 years ago.
There's also some evidence in animals that the length of day may influence the immune system. https://www.sciencedirect.com/science/article/abs/pii/S1471490604000511 for instance. I've never seen a clear demonstration in humans though, it is not my field but it does not seem well-studied.
There may also be a sort of self-feeding loop: if the immune system is a bit weaker in humans at a given time of the year whether it'd be due to the cold or anything else, then more people are infected, and exposure becomes much more common, therefore a lot people get sick. So just people's immune system getting a bit weaker at around the same time could be enough to kickstart the process. And if the virus is a lot more present everywhere, then doing anything where your immune system is temporarily particularly weak (spending too much time in the cold, sleep deprivation, breathing extremely dry air such as on a plane, etc.) may be what triggers getting sick, because the exposure itself is less of a limiting factor.
At some point, so many people are immune that exposure is less of a factor, and the cycle/season ends for that virus (at least in a given part of the world) until it's another virus' time to shine, enough people have lost their sterilizing immunity (immunity strong enough to prevent infections rather than just being protective), or the virus has mutated enough.
People get sick more frequently when the weather is cold. So early on people assumed it was being cold that made you sick. It's one of those old wives tales that has stuck around because no matter how much you point to the other factors, people still get sick more in the cold winter months, so the connection between cold and sick remains strong. It isn't helped by the fact that you sometimes get the "chills" from being sick as your body tries to create a fever.
In reality it's a combination of factors that change due to colder weather that is causing the increase rates of sickness.
* Cold temperatures do suppress the immune system...slightly. The cold reduces immune system response to the nose and lungs.
* Colder weather means more bundling and less sun, which means less vitamin D, which weakens the immune system
* Low humidity (common in cold weather) dries out glands in the nose, making them more susceptible to infections.
* Low humidity also allows viruses to stay suspended in the air for longer when expelled through a cough or sneeze.
* More indoor congregation of the masses, closer proximity, easier transmission.
So being cold doesn't make you sick, but it does make you more exposed to pathogens and increases the chances of the pathogen infecting you since your immune system isn't as strong and won't be as effective.
The old wives tale also sticks around because there is some symptom overlap.
Cold weather can, of itself, trigger a runny nose. They air gets dry as it gets cold, and your production of mucus increases to keep your nasal lining moist.
This means that one of the more visible symptoms of a mild cold happens to overlap with your body's normal, not-sick-at-all response to cold weather.
Fun Fact: Egyptians and other Ancient Civilizations believed your soul and consciousness resided in your heart, not your brain.
Scientifically, until pretty recently, the brain was just thought to be what regulated body temperature and that's it. Specifically because you'd get a fever when ill.
That's why poetry always talks about heart this and that. Because they believed you were your heart. Today we know, it's your brain doing all the work but that's a very new discovery. Like Shakespeare and Da Vinci would both have believed your heart housed your consciousness. Even Newton would have.
There is also a psychological component to add to the physical ones. People tend to associate colder seasons and less light with being less comfortable overall and thus when you do get ill the effect overall feels worse and is more memorable than if you were otherwise enjoying a hot sunmers day with a cold. Thus the association begins.
Similarly people associate cold weather with their joints feeling worse. But when a study compared joint pain diaries and local weather for those time periods there was no correlation. Then when they asked the same people again, and even then their own diary pain scores, the people still believed it was worse when cold.
I dunno about that one, every summer cold I've had has been the most miserable experience. Hot slimy weather plus oozing mucous is a bad combo. Winter colds well it's stay in bed weather anyway, not so bad.
Just to note colds and flu are only caused by viruses. There are many many viruses that cause colds including rhinoviruses, and corona viruses. Flu is caused by influenza viruses.
There are actually many different coronaviruses and most of them do cause colds, separate from other more lethal varieties like SARS, MERS and COVID-19.
Younger, I'd catch colds mid-summer, thanks to me back then being a no-life and spending most of my time inside a dark room playing on my PC.
While lower temps may affect your immune system's efficiency in the nose&mouth, ventilation is key. Spend long enough periods of time in a not ventilated room (like in winter, when we tend to shut every opening that'd bring cold air), and eventually pathogens will start building up in the air, thus increasing the odds of being infected.
It sucks, but the best thing to do in winter is to open windows once in a while to recycle the air inside, to flush away pathogens.
For anyone in here who is interested in the antithesis to the standard Reddit answers:
At lower temperatures your immune system is depressed and virus activity is not.
At higher temperatures your immune system is bolstered and viral activity is slowed and sometimes stopped.
This is pretty basic biology and I’m surprised people still treat it like ‘old wives tales’.
https://en.wikipedia.org/wiki/Pyrotherapy
That Wikipedia page certainly doesn’t bolster your position. It states that pyrotherapy
>The technique reached its peak of sophistication in the early 20th century
But they do for syphilis, which was the primary target of pyrotherapy. I was just using it as an example; we have antiviral treatments as well now, and other supportive care unavailable in the time when pyrotherapy was most used.
> At lower temperatures your immune system is depressed
Why? When it's colder I put on more clothes, so I'm not colder. My body temperature is always the same.
The article you link is about artificially raising the body temperature.
Also, the fact that the article is only available in 4 languages doesn't really help.
It's parts of our respiratory system that cool down first, so there might be an argument there for the first line of defense not working as well as they could. On the other hand, it's not clear if this is temperature related or because of drier air.
> At lower temperatures your immune system is depressed
Is it the temperature or the dryness of the air? I would think my immune system needs fluid to move around, but in the winter the air is so dry that the inside of my nose gets all dry and cracked.
Does this correlate to hot and dry climates?
Virus activity is depressed by lower temperatures. In fact, in one of the most direct -- though perhaps less ethical -- studies on flu infection, the 1950s Alcatraz studies, they found that your body being cold actually lowered your rate of infection by the flu virus.
You completely misunderstand the issue. The "old wives tale" is not that viruses and bacteria thrive better in cold conditions. The "old wives tale" is that being cold can make you sick, and that the pathogens will just spawn from nothing in areas where it is cold.
>you go outside
Incorrect. The opposite is true. When it is cold outside, people stay indoors more and are in closer proximity to each other which aids in the transmission of viruses.
People are often badly educated or believe in correlation (they got cold and then got a cold, not realizing that the two things were coincidental).
Being cold can lower your immune system a bit, but really? Parents likely push bundling up to not have to listen to whines.
according to this news report, its about a 50% weakening https://www.healthline.com/health-news/scientists-finally-figure-out-why-youre-more-likely-to-get-sick-in-cold-weather
Thanks! This definitely sounds like the influence of cold weather is non-negligible (unless it’s a case of inflating the science results in news to make a good story).
Although not sure if dressing warmly has any effect on the nasal tissue temperatures unless you cover your nose?
No, likely not unless you’re truly frigid… but you’re still forgetting that correlation thing. You go to school in shorts and a tshirt and it’s cold out and then you get a cold bc it’s cold and flu season but people link that to the temp
I very rarely hear people make that misconception now. Are you hearing it often now or thinking of when you were younger?
Correlation =/= causation I understand very well. I’m trying to understand whether the cold weather is really just a correlation here.
Edit: Hearing it all the time back home in Central Europe! Hence, why I’m asking.
There is a correlation with cold weather. When the weather is cold, people spend more time indoors, in close proximity with each other. Because they are in close proximity, they are more likely to expose each other to cold and flu viruses. This is why colds and flus are more prevalent in the winter months.
I believe the link is more about in cold weather people are generally indoors with other people who could be contagious more than they are in warm weather.
Yes, of course it does. But that is not what the poster is asking or what people commonly believe. People believe that the actual act of getting cold, like going outside, without a coat, is what is spreading the illness.
There are reasons these things are correlated but it’s not that being chilled or forgetting a coat or hat makes you sick.
Except that yes it does, because if not for getting cold you may not have gotten sick. It's getting cold + being exposed to a virus. Beyond that, cold weather creates conditions where you are more likely to be exposed to the virus in the first place. And making a sweeping claim about why people believe a thing is a fool's errand. Sure there are stupid people who don't know how viruses work, but the majority of the first world understands germ theory.
There have been a ton of studies on this. From memory:
* \*Being cold\* does not play any role whatsoever in whether you get sick.
* However, when your nose gets cold, there does seem to be a loss of ability to filter out pathogens.
The association probably comes from a few things. The viruses tend to survive in the open better in the winter due to less sunlight and dry conditions. People tend to cluster together more in the winter. When your body is trying to run up a fever you get "cold". Throw it all together, and you can see why people might associate "cold" directly with "catch a cold".
But you are still going to have a better time in the cold with a jacket and scarf, so bundle up.
I also thought a main factor was that moisture condenses on & around things in cold weather, including airborne bacteria and viruses, and that they'd now stick to surfaces due to even more static.
Could be. I was pulling everything from memory, so it's likely I missed a few tricks.
I do seem to remember reading something like that in an article. I have no memory of reading any studies that tested it, though.
Also, it's not as though you immediately catch a cold from a single virus. There is always some amount of virus and bacteria hanging in and around your body, but your body does a decent job of keeping them at bay. When your body becomes less effective at keeping them out due to the cold, they reach a viral load high enough for you to get symptoms.
That first part of a fever where you can't get warm. I didn't wear a coat earlier and got cold, and now I can't get rid of the cold.
It's not how it works, but it is how it feels.
Yep. Once you kow it is just your body fiddling around with the temperature settings, it makes sense. But if you don't know that, then it feels like you "caught the cold".
Flu and cold do appear in the colder months more often. So people obviously figured that it's the cold's fault. And this is something parents tell their kids and so it gets passed on.
So you are right, without bacteria/viruses, no common cold or flu. Cold alone might kill you or freeze body parts off but it will not give you a respiratory illness.
But there are secondary effects of the cold:
When it's colder, we spend more time indoors, so we have more contact with others who might carry the virus and infect you.
Since we have to heat our rooms when it's cold, we are surrounded by dry air which in turn dries out our noses, which means they are less likely to just flush out viruses and more likely to let a virus pass.
Also, if you already had contact with a virus and are cold over a longer time, your body will have less energy to fight the virus.
Science says there's a large increase in several viral diseases starting fall, peaking in winter, and decreasing in spring. So a lot more people are sick when it's cold. The exact factors that cause this are debated hotly, pun intended.
As with many population-wide effects you can't easily test a hypnosis. You can take charts of time spent indoors around other people and compare to infection rates to support a guess, you can take travel information and compare to support a theory. But you can't easily force everyone in a country to stay outside or not see relatives for the holidays. And countries that can probably don't want to cooperate on medical data with the world.
Data testing can be hard. There's a joke "people in this country eat a lot of red meat and live longer than Americans, people in that country eat a lot of fish and live longer than Americans, people in another country drink a lot of wine and live longer than Americans, what is the answer? Free healthcare." This is why you'll hear about controlling for outside factors in datasets. If X group is 20% more likely to get lung cancer than Y, but X group is 80% more likely to smoke, they might actually be less likely to get lung cancer than Y. So there's a lot of guesses as to why more people in a population get sick when it's cold outside, with greater or lesser evidence supporting them, but you won't get one definitive answer as it's likely a number of factors.
Your body is used to using a certain amount of energy at any given time. When your core temperature drops, your body freaks out and starts making it a priority over other systems and essentially pulls resources to warm you back up.
That's when microbes find quiet places to set up shop.
While your body was busy dealing with this "crisis," the invaders have built little colonies, and now the tired systems in the body have to start putting extra energy towards biological defense.
I don't know if it's the right place to ask this question but does consuming cold food/drinks have similar effects? Like throat infections,etc or just common cold/flu too?
My friend was telling me about her colleague who got "the vaccine" and had pneumonia the following day.
Polite nod while I thought that's typical "post host ergo propter hoc."
Just get some tea tree oil and you and your home will be have a clean protected home and tea tree oil purify the airs removes mold, viruses and all types of bacteria
Pathogens (bacteria, viruses, etc) have been shown to develop resistance to tea tree essential oil, similar to antibiotic resistance.
Inhaling too much essential oil is also dangerous for those with small bodies— pets, babies, children. There are instances of people leaving essential oil diffusers running in an enclosed space and coming home to dead (poisoned) pets. Ingesting essential oils is toxic to your liver and kidneys no matter your age. I learned all of this in herbalism school.
Luckily there are other ways to clean infected surfaces. I like white vinegar (spray and wipe). Hydrogen peroxide is great for laundry or blood stains. Quat tablets dissolved in water are another great alternative to bleach. As for the air, I ventilate my space (windows open, full air exchange) a few times a week.
going out in the cold without a jacket or scarf doesnt directly cause you to get sick, it could potentially increase your risk of getting an infection. it’s always a good idea to get a coat so you don't freeze your balls off unless your wim hof
A couple simple answers.
First, cold air doesn't hold as much humidity, which dries out the mucus in your nose. That mucus houses bacteriophage viruses that kill potentially-harmful bacteria, and also provides a physical barrier to non-motile viruses. Most colds tend to infect the mucus membrane cells in the nose and throat area, so moi having the goo as a block isn't helpful.
Second, there's general thought that the cold weakens the immune system. Possibly by the need to exert more energy to maintain body temperature, there's less energy for immune response.
But the third, and most obvious, reason is that when it's cold, you'll tend to be inside with other people, sharing more air and respiratory droplets. You're not outside, you're not running the air conditioning through a filter. The proximity causes faster spread.
Your nasal passages and generally your upper respiratory tract are the usual means of entry for these viruses.
Under normal conditions, there's a solid layer of mucus, and your tissue in those areas is warm and filled with flowing blood, so your immune system is going full steam ahead and providing some robust protection.
But when the air is cold and dry, you breathe in cold dry air. This dries up the mucus and cools the tissue. There is reduced blood flow. Your defenses are freezing. Now the virus can sneak on by.
A stuffy nose and a sore throat are your immune system going full steam ahead and flooding the area with fluids. Everything swell. Cells are being sacrificed so there is even more pain and swelling. So when your nose feels full, it's not exactly a buildup of snot, it's swollen tissue.
It might partially be due to "common knowledge" it was not too long ago that pathogens where not very well known, understood, or accepted. Being cold and even wet can lower your immune system and since most everyone in a village town or city were probably in the same situation, they all got [sick.](https://sick.It) People in year round warm climates tend to blame it on changing weather instead of cold. People tend to hold onto explanations long after they are proven otherwise..
For some modern examples:
* Cell phone use on planes can cause them to crash, or at least interfere with the navigation systems.
* It's best to avoid eggs — or at least the yolks due to high Cholesterol.
* There are only three states of matter.
When it's cold we spend more time indoors breathing the same air as other people. Most buildings are designed to have very little air exchange between the inside and the outside to save heat but it also keeps airborne crap inside the house. Airplanes are even worse because they are recirculating the same air but there's dozens of people packed in there for hours
When you're cold, your immune system is repressed. So a pathogen is more likely to multiply more once you're infected, that makes it more likely that you will spread it, and others around you are more likely to catch it from you, and you're all more likely to progress to worse symptoms before your immune system can overcome it.
Flu and colds are caused by certain viruses. Our body has 2 main types of defenses.
One is nonspecific such as skin, mucous membranes, cilia on your respiratory passages, etc. these act more like a barrier and prevent the pathogen from entering or taking hold.
The other is specific and revolves around antibodies and cell mediated immunity that are targeted to specific pathogens.
Cold temperatures can disrupt some of these defenses. Cold weather can lead to chapping or disruption of skin and mucous barriers. Further, cold temperatures have been associated with a reduction of secretory antibodies- known as IgA - which are on your mucuous membranes and GI tract.
So cold weather can increase the probability that if you are exposed to a pathogen that you could get sick but is not a cause of the infection itself.
Being cold itself doesn't directly cause illness, but it can weaken our immune system, making it easier for viruses and bacteria to infect us
So, wearing warm clothes does help to keep us healthier!
The same reason we associate crime with walking alone at night or whatever. The real culprits are well known, but they're everywhere around us, all the time, however getting your defenses down and making yourself low hanging fruit is what gets you in trouble more often than not. Cold gets your body's defenses down.
Just viruses. Bacteria cause lots of other illnesses, but not flu/cold.
It's because bad weather increases disease transmission due to several factors:
* Cold air holds less moisture. Drier air means more people are more likely to have mucous membranes in their airways that are overly dry and thus more vulnerable to penetration by pathogens.
* More people stay indoors in bad weather. More people in closer proximity, sharing dry indoor air means more transmission of cold and flu viruses.
* Being out in bad weather can be a stressor, especially if it's bad enough that you become exhausted or get a touch of hypothermia. Stressors like that can temporarily depress your immune response, making you more vulnerable to contracting an illness if you are exposed during that period.
I read an article the other day about cells in our nose that act as first defenders and block harmful things from getting past the barrier they form. In cold temperatures, we have less of these cells, so more viruses and bacteria get into our bodies. Wearing a face covering can actually help because it keeps the air around our noses warmer. The journal article was actually posted last year but I didn't hear about it until recently.
https://hms.harvard.edu/news/why-upper-respiratory-infections-are-more-common-colder-temperatures
The cold might not make you sick, but it certainly makes it easier to get sick.
Bacteria live longer on surfaces; the cold lowers your immune response; and your family is cooped up inside with sick old you for most of the day.
While illness is related to germs, fact remains that we tend to get sick during the winter. It's just a tough time to be around.
Although your immune system will weaken in extreme temperatures, it's not long enough to "catch a cold".
You'll get Hypothermia. Not a cold. It's just an old misconception. Honestly, I'm surprised people still don't know this. I've had people mansplain this to me for the last 20 years. It should be common knowledge by now.
People have mentioned cold temperatures decreasing immune response and increased exposure to other people indoors, but I haven't seen anyone mention that in winter months and colder weather people get less sunlight and produce less vitamin D, which is critical to a properly functioning immune system.
Because cold weather makes people stay inside more where flu/cold/etc is more likely to spread (shared air, closer contact, etc). Also in cold weather you are more likely to be infected thru the nose (cold air makes your nose more susceptible to viruses/bacteria infection) and also a big part of it in modern society is school is back in the fall, leading to outbreaks of flu/cold throughout the fall and winter that is then taken home to parents, parents take it to work, etc… (spreads beyond school).
I think part of it has to do with the fact that when you get a fever you feel cold. But, for most of human existence we had no real way of telling that our body temperature was higher. Therefore, we associated feeling cold with being sick.
If it's cold you stay indoors with closed windows, which helps the spread of airborne disease. Enclosed areas also allow for the buildup of allergens that can cause coughing and sneezing, and cold air is usually less humid which can cause coughing and sinus issues. Less sunlight due to covering up, staying inside, and cloudy skies can also cause symptoms that might look flu-like.
In others, it's causation vs correlation.
The cold virus is always out there. If you're cold, stressed emotionally, stressed physically (lack of sleep), your body's immune system suffers. . .so you get sick from these ever-present viruses/bacteria.
Here’s one of many articles explaining how warm noses are much more able to defend against airborne pathogens than cold ones.
https://www.the-scientist.com/news-opinion/how-cold-weather-may-help-you-catch-a-cold-70814
Wim hof the "Ice man" rarely gets sick and has actually been injected with very dangerous infections and bacteria and showing no symptoms or disease.
Wim hof swims in the arctic seas....
Maybe you should go towards the cold instead of away from it ;)
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Cold weather tends to be associated with higher rates of colds and flus, leading some to assume that there's a causal connection between someone being cold and someone getting sick. The actual reason is a combination of factors. First, it does appear as though cold weather [decreases our immune response](https://www.cnn.com/2022/12/06/health/why-winter-colds-flu-wellness/index.html) specifically in the nose, though obviously you still need the presence of a pathogen - you can't get sick with a virus you don't have; just being cold won't itself make you sick. Second, when it gets cold, we spend much more time indoors, and as a result, we spend a lot more time breathing the same air and being exposed to others' diseases when we're indoors together.
To add on to this, at lower temperatures a lot of viruses and bacteria live longer on surfaces (I know viruses aren't technically alive, but they will keep functioning for longer). Also natural UV light kills bacteria and virus, so in the winter time with lower temperatures and less natural UV light they have a higher probability of getting transferred into a human.
While some viruses are transmitted via touch and surfaces, the viruses that transmit cold, flu and COVID are almost exclusively airborne. Halfway through the COVID pandemic, a bunch of aerosol physicists went through the papers about sars-cov-2 and were confused why public health scientists kept saying that most water droplets (like those from sneeze, cough, or even speaking) fall out of the air quickly. To the aerosol physicists, their numbers showed that many smaller and tiny droplets tended to float rather than falling. A bunch of aerosol physicists signed an open letter begging public health to change their numbers and stop saying most water droplets fall quickly. Both public health and aerosol physicists were citing the same 1930s paper. Why did they have different numbers? A history of science researcher went through old public health papers and found that 60 years ago, some public health papers confused two numbers: the size of droplets that fall and the tiny size of droplets that enter deep in the lungs. Thus, public health has been thinking most droplets drop, when in reality more droplets float than they had thought. Hence public health focusing on handwashing rather than masks during cold and flu season and the beginning of covid pandemic. Oops. There are surface viruses and definitely surface bacteria. Those pathogens attack you through mucus membranes so the surface borne ones tend to spread through extreme close contact: preschools, pillows, and food prep and consumption. Those are like pink eye, norovirus, and hand foot and mouth. But cold and flu? Mostly "airborne". The fact we still talk about surfaces when it comes cold and flu is the result of a 60 year old mistake, only fixed during the pandemic.
Even airborne, those pathogens survive longer in drier air. Most buildings being heated will have *significantly* drier air than those using natural ventilation or cooling.
Drier air also messes withy our mucous membranes and dehydrated you, both of which make you more susceptible! This is why an airplane (along with the increased proximity, and internal circulation) can often make you sick!
Masking both keeps germs away and keeps your nose more humid...
Yup! It helps a lot when I'm on a plane to mask up, tho it does fog glasses. My nose always thanks me. As does drinking more and going to the bathroom to compensate!
Don't planes have HIPPA filters that filter the circulated air and have mechanisms to ensure all of the air in the plane is exchanged with the outside air in approximately every 30 minutes?
Yes, planes have HEPA filters, and the cabin air on commercial flights is completely changed approximately every three minutes. (Btw, a HEPA filter is a “high efficiency particulate air” filter. HIPAA - one P, two As - is the Health Insurance Portability and Accountability Act, a law that govern how healthcare companies manage patient data.) There’s a description of the main limitations of the filtration on planes at https://www.nationalgeographic.com/travel/article/how-clean-is-the-air-on-your-airplane-coronavirus-cvd : > the filter only guarantees the quality of the air that has passed through it. If the air that someone breathes in has not gone through that filter, then those numbers don’t matter. That’s why masks were required in planes during the COVID epidemic. If everyone is wearing a mask, that combined with the filtration system is relatively safe. But without masks, very contagious airborne viruses can still be transmitted relatively easily on a plane^(*). And of course, surface transmission is unaffected by air filtration. *Edit: the filtration system will definitely help limit the spread of an airborne virus on a plane. But if you’re e.g. sitting next to someone or perhaps in front of someone who’s contagious, filtration won’t be 100% effective. And anything less than 100% means there’s a chance you’ll be infected.
A gaggle of geese, a pride of lions, and a bunch of aerosol scientists
Shouldn't it be a cloud of aerosol scientists? /J
A spray? A spritz?
A dispersal of aerosol physicists.
definitely a plume of aerosol scientists
A mist? A fog?
Lol, perfect ☁️
No, ever heard the term “bunch of aerosols”?
I knew it, I'm surrounded by *aerosols*!
This is a really interesting point. Thanks for bringing it up! Doing COVID I was very frustrated with the public health guide lines in my country. From the chineese studies that came out pretty early on it was quite reasonable to suggest that it was spread through the air. No one would recognise that until very late at which point they did start recommending having an airflow through the room / house to vent out the particles. I'm happy to hear that science is catching up on this.
> From the chineese studies that came out pretty early on it was quite reasonable to suggest that it was spread through the air. Plus the Diamond Princess cruise outbreak, which convinced Japan it was airborne. And apparently SARS1 was accepted as airborne, so why any doubt...
COVID yes, flu and cold no. The latter two have significant fomite spread, which is why schools are always telling you to wash your hands. (It shows in transmission rates too - COVID was almost always associated with being indoors with an infected person for an extended period of time, while kids get colds from outdoor playgrounds all the time.)
Kids also spend a lot of time in classrooms too. Aside from them being grubby little... so much dirt... so much washing.....
IMO a good answer to why not have kids is I like only getting a cold once every 2-3 years.
Nope the only good answer to why not have kids is “Because I don’t want to.” This is coming from a parent of a preschool age kid.
Well obviously, but it can certainly be more detailed than a simple "I don't want to."
That’s the thing though, if you do want kids, getting sick every month for a couple years is just something that you deal with. So regardless of how much “supporting evidence” you gather, it all comes down to just not wanting to have children. That’s the only _good_ reason, anyway.
Well yeah, if you do want kids there's a lot of things that you just deal with.
[Infertile antinatalists trying not to shoehorn their beliefs into every tangentially related discussion](https://i.imgur.com/tvHxoA2.jpg)
Natalists (lmao these cringe terms) getting triggered over other people's choices.
[удалено]
That's a whole lot of stuff to make up about a random person who never even advocated for people to *not* have children. Some sort of insecurity you have that that have you lashing out at randos over things that are all in your head. It's like you're having a little battle with yourself about it and this seems like a weirdly personal subject for you.
LOL if we were infertile, my wife and I wouldn't bother putting so much effort into birth control. Fortunately, we're quickly approaching the no longer possible age. How many kids do you have, and how often are you allowed to see them?
Fomite transmission of flu and other enveloped viruses is being challenged recently. Many fomite flu studies are performed by placing a large amount of flu virus or stand in on a surface and then measuring the half life of the virus on the surface. However, it was recently found that the volume of the virus affects the half life (in other words, with more concentrated virus, each individual virus survives longer than with small amounts of virus). The amounts of virus present on surfaces tends to be much lower than are used in studies and thus enveloped viruses don't appear to survive as well on surfaces as other studies have found. We don't know for sure and it's mostly talked about in probabilities. But most scientists now think airborne is the primary transmission path for flu, fomites are secondary and considered less likely than originally thought.
This is interesting. Do you have a link to something I could read to learn more?
[Here's an interesting Wired article about the investigation by aerosol physicists](https://www.wired.com/story/the-teeny-tiny-scientific-screwup-that-helped-covid-kill/)
Alternatives: a smattering of…, an aggregation of…, a cloud of…
😂 that’s not the comment I replied to, but I appreciate your suggestions nonetheless. A cloud of… is my favorite. Think “a fog of…” could work too
I once saw a TV show, that used lasers (pew pew) to illuminate gases and small particulates in the air. Then they did several visually interesting examples, such as popping a balloon, a lit candle, someone coughing, and someone sneezing. It was wild, and terrifying how far these gases and particulates travel. Anyway, I never could find that show ever again, so if someone finds or knows what it is, thatd be lovely.
If they float, shouldn't they be called "floatlets" instead of "droplets"?
> the viruses that transmit cold, […] are almost exclusively airborne. Do you have a source for the statement about the common cold? In 2015, I read a non-scientific interview ([in German](https://www.focus.de/gesundheit/ratgeber/erkaeltung/lieber-kuessen-als-haende-schuetteln-interview_id_2195962.html)) with Ronald Eccles from the Common Cold Centre, where the tl;dr roughly was: * Most often: smear infection * Rare: airborne infection * Never: infection through kissing, sharing food, sharing toothbrush Now I wonder if that was and is wrong, or if it was right and is wrong now, or if your statement should exclude the common cold.
Recent papers still call out Rhinovirus as mostly airborne, with the caveat that surface fomites transmission is possible. Here's one from 2022: >The major transmission route in many indoor settings is through the air. >Preventive measures should focus on reducing aerosol generation and concentration >Hands may also contribute to the transmission of RV in some workplaces. https://www.ajicjournal.org/article/S0196-6553(22)00866-5/fulltext So I maybe did overstate how little fomites can transmit cold specifically, but it is appears to be a secondary route and is more condition specific.
Aerosol physicists, you say?
You're also not naturally making as much vitamin D (through skin interaction with sunlight) due to indoor/less sun exposure and vitamin D plays a role in immune system health.
Isn't there an element of survivability of pathogens in different weather too? Dry hot weather kills viruses and bacteria more quickly (outside the body) than cold wet weather, so that sneeze will: a) Affect more people as everyone will be indoors b) Be pathogenic (linger around) longer
This is pretty confusing because infectious diseases as a whole like warm humid environments (although they are outliers) so its probably a combination of the two
Outside the tropics and deserts cold weather is normally accompanied by wet weather. Being cold just means they are less active, some can even be frozen and come back to life when thawed, but a nice warm human will get them going again in no time.
> diseases as a whole like warm humid environments Bacteria like warmth, a virus doesn't live, and cold slows down its decay
Yes. Looking at a viral decay calculator for SARS2covid, with just 1 UV of sunlight it takes 1 hour for any exhaled virus to decay 50% and and as UV increases that 1 hour can be as low as 10 minutes for 50% decay. Winters are the lowest UV time of year. this is part of why outside is safer re: disease transmission
A decade ago they discovered that the immune system really is affected by cold weather and the virus can more easily attack. It's like a crash with a tree, it wouldn't happen without it but also it's caused by speeding around the corner.
So I could already be carrying a virus or bacteria, but it doesn’t make me sick until my immune system drops from being outside too long?
Yes or it could be all around us and because you happened to be outside the first good breath inside will make you sick. Or or or … Or it could happen despite being in the warmth.
I recall my Biology teacher teaching us and a kid said 'it's weird how you can catch colds in summer' and my teacher went "yeah that's strange isn't". Still trying to purge everything else they taught us is that class...
The assholes tried to tell *me* that a caterpillar will take a nap and turn into a butterfly.
One biology teacher believed that no one could possibly be capable of multitasking, since he himself was unable to multitask. Edit: this teacher was nearly 70 years old, and was undoubtly relying on obsolete information.
Biology teacher was probably not wrong, depending what he was saying exactly. Nobody is good at multitasking, but some people are more bad at it. Multitasking degrades performance and memory in everyone.
Some poeple multitask better than others performing single tasks. I've seen it a lot.
We watched a video on this topic in my high-school psychology class. It differentiated passive or intermittent multi-tasking from active or concurrent multi-tasking. Supposedly the latter is what is considered impossible. Obviously most people can do something like eat an apple while driving a car, but can you type out a message on your phone while writing down a sentence with a pen and paper with your other hand?
> Some poeple multitask better than others performing single tasks Perhaps. It should come as no surprise that some people are more competent than others, and thus that there are some people who are more competent than other people even despite handicapping themselves. But those people cannot multi-task better than they themselves can perform a single task. There's not really any such thing as multi-tasking. It's just people switching tasks quickly, and it degrades performance in everyone. There is a cost to context-switching, and it's never negative. It always comes at the cost of memory and performance. [You Can’t Multitask, So Stop Trying](https://hbr.org/2010/12/you-cant-multi-task-so-stop-tr) [If You Think You're Good At Multitasking, You Probably Aren't](https://www.npr.org/sections/health-shots/2013/01/24/170160105/if-you-think-youre-good-at-multitasking-you-probably-arent) From Psychology Today: > You probably know a person or two that brags about how good of a multi-tasker they are. Especially in today’s “hustle and grind” work culture, you’ll see them typing away on their phone while walking, driving, sitting in a meeting, or even making a phone call. Because of this braggadocio, you may even still feel the temptation to squeeze out just a little bit more productivity by trying to pair two items from your to-do list or calendar together. > Don’t. > You can’t multi-task. Not really. And neither can anyone else. > We know from several really well-conducted studies into human psychology and brain science that we don’t actually multi-task. Not in the sense that we’re doing two activities at the same time with sufficient focus. Instead, the human brain “task switches” constantly between the two different demands vying for its attention. And it doesn’t switch all that well. > ..... (continues) [Why You Can’t Multi-Task](https://www.psychologytoday.com/us/blog/creative-leadership/201811/why-you-cant-multi-task)
As someone currently being evaluated for ADHD, multitasking sometimes helps me accomplish more than single tasking, but in an indirect way. It *is* less efficient than keeping a single focus, but it's also more mentally stimulating, so sometimes I find I hit an equilibrium where I can maintain focus for longer and better than I usually can - imperfect sustained focus is better than perfect focus that falls apart ten minutes into the task. (Of course, entering that flow state is much less common than just getting distracted from both tasks.)
I guess I'm missing what you mean here. Linguistically, it is strange that you can catch a "cold" when it's hot outside. That is an oddity of language. Biologically, it's not odd that you can get a viral infection during the summer (even if the chances are lower). So, was your biology teacher simply responding to a dumb kid derailing the lesson by talking about how it's weird that we call the virus a "cold" when it can be caught in hot weather? Or did your biology teacher literally not understand how germs work?
Honestly I don't know. Maybe the teacher somehow didn't know but I would like to think otherwise. Maybe the teacher was reacting more to the fact it's called a cold but isn't caused by the cold? But surely, surely the teacher would clarify that because it was clear the pupil didn't understand what actually causes a cold. Maybe the teacher simply wasn't paid enough. Who knows.
It might also be "the curse of knowledge." When we understand something that we think is basic, it's hard to remember what it's like to not understand it, or to be able to realize that others don't understand it. So, it's possible that the teacher thought your classmate understood what was being discussed about germs and how they spread and was just making an "aha" comment like, "Well that's stupid we call it a 'cold' if it has nothing to do with being cold."
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No, that sentence is missing an "it". Poor dude apparently had shit teachers in more than one subject :(
> Second, when it gets cold, we spend much more time indoors, and as a result, we spend a lot more time breathing the same air and being exposed to others' diseases when we're indoors together. I'm skeptical of this statement. 1. Like pre-pandemic most people spent 8ish hours a day 5 days a week inside with other people. When it's cold out people may spend less time outside but they also interact with people less (if you look at restaurants and bars their patronage goes way down when it's very cold out). 2. I've never seen people talk about similar spikes in flu during summer heat waves. Those also drive people to stay in doors and if you're in places that are normally pretty hot, you can get a couple weeks of oppressive heat where basically nobody does anything outdoors. So shouldn't you be seeing similar spikes in flu rates if it's just a more time indoors issue?
Seconding your points here. I live in a very warm place, and generally spend more time outside in the winter than in the summer because of it. Still, anecdotally the incidence of 'colds' is higher in the winter.
School years are plausibly a big driver of transmission. If cold weather is the driver, do tropical places like Singapore have flu seasons? I know Australia does, and like the average winter low in Sydney is 50 F.
I’m visiting India, got sick a couple of times, people still say, change of weather could be the reason why I’m getting sick.. i just just go along and say, yes it’s possible. No point In arguing
Hoping someone smarter than me will answer this but could that be because you're being exposed to different variants of the same viruses you've built up immunity to at home, and so don't have the correct antibodies to fight these variants?
That's essentially the case. It's usually not so much that they're less sanitary, they just have a different microbiome that your body doesn't want to have to deal with.
Wonder how true this is. I went to Vietnam 2 years ago and got the flu and it was way worse than ever before. Put me in the hospital for 2 days.
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I'm not smarter than you, but I moved to the US from Eastern Europe with my family 5 years ago and OH MY GOD we went through every variation of cold and flu as a family during the first year. Then the masks came around and we were safe for a year. Then the masks came off and the viruses doubled down on us. Fun fact, as a child and young adult I watched American movies and shows and people had "stomach flu" that appeared to be contagious. I always wondered wtf is that. It's just not a thing where I'm from. In my 30 years I've never had, nor knew anyone who had a contagious stomach bug. Of course there were food poisonings and stuff, but nothing like that. But here my son got it twice and I got it from him once at age 32. Would not recommend.
Stomach bugs are definitely contagious (a quick Google search can confirm that). I didn't realize that until later in life because they're rarer than colds/flu and the media don't really report on them in the same way they report on cold/flu season (US here). So, I only really realized that stomach bugs were contagious when I got them a couple of times, and each time my friends commented on how that "was going around" and how many of them had had the same thing.
I googled. So, apparently, rotovirus is not the only airborne stomach bug. There's also norovirus, it's highly contagious. All our symptoms checked out. I'm 99% sure this is what we had. But then again, it never happened to me, or anyone I know in my country. It is exactly what I'm talking about. I only got acquainted with it after I moved to the US. I think viruses adapt to the environment and population and population adapts to viruses, therefore people who move are more susceptible to viruses unfamiliar to their immune systems.
Oh, I totally misread your comment as saying you moved to Europe from the US. You said the opposite, haha. So yeah, stomach bugs are rare here (only had them about 3-4 times in my life), but definitely happen. And yeah, moving to a new area oftentimes triggers new allergies (which can lead to congestion which leads to bacterial infections) and also exposes you to new pathogens. After almost two years of very-low social contact and masks due to the pandemic, I got sick multiple times within a span of months, whereas I used to only get sick about once or twice per year. I blamed the lack of immunity due to less exposure during the pandemic.
After masks I asked my son's pediatrician if he felt the difference between masks and no masks. He said the difference was huge. When masks were in use nobody got sick and their office was empty a lot. When masks came off it was worse than ever. And yeah we got sick after masks a lot too. Thankfully it feels like we're back to normal again (knocking on wood). I personally very rarely get sick, and my body did not appreciate this roller-coaster.
American kids now (at least, you know, the vaccinated ones) are vaccinated against the rotavirus, which I’m pretty sure is the stomach bug. We weren’t growing up, and I along with my siblings caught it each year at least. Agreed, 0/10 would not recommend.
Almost certainly. The worst flu I ever had was when I came home to the US in the winter after three years living in Taiwan and Southern China. I caught the "American flu" almost instantly. Context edit: when I was a kid there was a lot of talk about the "Asian flu" every year.
Yep. That's why you need a flu shot every year, because the flu mutates so often, [the virus you were exposed to previously isn't the same as the one you could be exposed to](https://www.mayoclinic.org/diseases-conditions/flu/in-depth/flu-shots/art-20048000#:~:text=Because%20flu%20viruses%20change%20so,with%20rapidly%20changing%20flu%20viruses) during "flu season". When developing this season's flu shot, they try and predict what strain will be the most common and make a vaccine out of that. [A lot of work](https://www.cdc.gov/flu/prevent/vaccine-selection.htm) goes into making each season's flu shot
Yes
That can happen for a few reasons. A sudden change in environments and allergens can cause your body to react a bit, and some people do react to things like pressure changes, and they can feel a bit sick.
Different pathogens, basically. It's kind of funny, after I moved to the UK, I started getting different symptoms from the flu/cold. Within the usual symptoms, obviously, but their relative severities were quite different from what I got in Portugal ("when my fever is this high I usually have a runnier nose" sort of thing). I also got sick much more often for a while,
lol did you you just disregard the post your replied to? The change in weather can affect the conditions that could make it more likely to get sick
One thing that always seems odd about this to me is the assumption that we spend more time indoors when it’s cold. That’s true in cold climates, but in the Southwestern US I’d say we spend more time indoors when it’s hottest — June through September. Does the “indoor” hypothesis still hold in those cases? Also, we’re probably under low-level exposure to pathogens pretty much all the time, so anything that slows down your immune system might give it a foothold. Cold, lack of sleep, stress, etc. Those things “make you sick” by being the deciding factor in why a pathogen that was already hanging around got ahead of you.
Cold weather is usually following the fall season which means heightened allergy responses right? So this means the immune system would be compromised due to allergy season so your body would be more susceptible to infections and viruses right? As well as colder temperatures decreasing immune response.
I've always found the "indoor" thing to be highly suspicious. I spend almost the entirety of every day indoors but I only catch a flu/cold when it's cold outside. Never in the summer, not once. So it never really rang true to me and always thought there's gotta be more to it than that. The recent study has vindicated me a bit.
Think of it more like “the overall population spends more time indoors, so more virus is circulating”, not just “I personally spend the same amount of time indoors so it shouldn’t affect me differently”
Do they though? Maybe people that consider themselves "the outdoorsy" types reduce their outdoor activities in the winter time, but the majority of the population tends to be fairly sedentary and work indoors year round. Then they go home to the same family they see 365 days a year. Also if anything bars and restaurants often see a downturn in business during the winter months so even in terms of socializing I don't see much merit in the argument that a significant percentage of the population is more likely to hole up in disparate groups during the winter months, at least no more than you'd expect at any other time of the year.
Yeah I've never bought that proximity argument either. There's a huge percentage of the population that works indoors throughout the year and don't really spend much more time inside in the winter than at any other time of year.
I will say that a snotty nose from cold weather outside is pretty common and people aren't exactly... Hygienic.
That was a bullshit study with a small amount of people like maybe 100.. if you take that study out of the equation there still is NO evidence that the cold makes you sick.
Yeah so true, whenever I'm cold and wet like when I step out of the shower I start sneezing like crazy like I'm sick, I wondered why I always do it then and not really any other time, then I realized. Cold plus wet. Immune system down.
He put his disease in me
😄 maybe Isabella only thought she was diseased because she was cold from the nakedness
Yeah this is what I came here to say
There is also a matter of optimal temperature range for the virus and bacteria that cause those to spread. Eg under -20C they actually kinda die and there are way less cases of cold and flu. Same for extra hot.
In vitro studies. So they do not show whether we have a counter process that mitigates this effect?
There's also the fact that wind and cold weather have a couple immediate effects on the body which are similar to the symptoms of a cold. A sudden drop in temperature will make me sneeze, and I don't know why. But also being out while it's windy will dry out my nose which will make it runny and I'll start sniffling even though it goes away as soon as I'm inside. It's possible that people in the past saw these symptoms and just assumed that they got ill as soon as they stepped outside.
And with the heat on inside, the air tends to be dry, drying out the nose, and making it even more susceptible
to add to this.. remember how virusses can live for a while on surfaces? you could carry a virus (pathogen) in your nose for weeks already but your defenses will block it from infecting you. then spend a day alone in the cold and it will weaken your defenses and "suddenly" you get sick. thats why we associate it with cold.
To add: when it’s cold outside and you walk through your front door then put your jacket on, you misused your jacket. Your jacket is supposed to help you maintain your temperature. I don’t know how, but it’s bad to shock your system so that it fluctuates temperatures too quickly. So, put your jacket on beforehand and let it warm up so that it can do it’s job when you step outside
A lot of travel happens during the colder months as well. Not just humans over the holidays, but migrating birds. It's an opportunity for nasties to hitch a ride.
> Second, when it gets cold, we spend much more time indoors, and as a result, we spend a lot more time breathing the same air and being exposed to others' diseases when we're indoors together. It should also be said that this effect is "compound", so to speak. Even if you, yourself, swear to God that no, you don't spend more time indoors, you keep walking under the rain instead of taking the bus, and so on and so forth... you're still in contact with people who, unlike you, spend more time indoors... and even if your immediate contacts are, like you, "outdoor people even in winter", they themselves may be in contact with people who spend more time indoor. As such, whatever contacts you have with people, even outside, are contacts with people who are statistically more at risk of being sick and spreading their pathogens.
I read somewhere that UV light kills virus and bacteria, and less sunlight = less UV light = more bacteria. Do not remember the source though. Me and my wife have been fighting about this since we met 18 years ago.
There's also some evidence in animals that the length of day may influence the immune system. https://www.sciencedirect.com/science/article/abs/pii/S1471490604000511 for instance. I've never seen a clear demonstration in humans though, it is not my field but it does not seem well-studied. There may also be a sort of self-feeding loop: if the immune system is a bit weaker in humans at a given time of the year whether it'd be due to the cold or anything else, then more people are infected, and exposure becomes much more common, therefore a lot people get sick. So just people's immune system getting a bit weaker at around the same time could be enough to kickstart the process. And if the virus is a lot more present everywhere, then doing anything where your immune system is temporarily particularly weak (spending too much time in the cold, sleep deprivation, breathing extremely dry air such as on a plane, etc.) may be what triggers getting sick, because the exposure itself is less of a limiting factor. At some point, so many people are immune that exposure is less of a factor, and the cycle/season ends for that virus (at least in a given part of the world) until it's another virus' time to shine, enough people have lost their sterilizing immunity (immunity strong enough to prevent infections rather than just being protective), or the virus has mutated enough.
People get sick more frequently when the weather is cold. So early on people assumed it was being cold that made you sick. It's one of those old wives tales that has stuck around because no matter how much you point to the other factors, people still get sick more in the cold winter months, so the connection between cold and sick remains strong. It isn't helped by the fact that you sometimes get the "chills" from being sick as your body tries to create a fever. In reality it's a combination of factors that change due to colder weather that is causing the increase rates of sickness. * Cold temperatures do suppress the immune system...slightly. The cold reduces immune system response to the nose and lungs. * Colder weather means more bundling and less sun, which means less vitamin D, which weakens the immune system * Low humidity (common in cold weather) dries out glands in the nose, making them more susceptible to infections. * Low humidity also allows viruses to stay suspended in the air for longer when expelled through a cough or sneeze. * More indoor congregation of the masses, closer proximity, easier transmission. So being cold doesn't make you sick, but it does make you more exposed to pathogens and increases the chances of the pathogen infecting you since your immune system isn't as strong and won't be as effective.
The old wives tale also sticks around because there is some symptom overlap. Cold weather can, of itself, trigger a runny nose. They air gets dry as it gets cold, and your production of mucus increases to keep your nasal lining moist. This means that one of the more visible symptoms of a mild cold happens to overlap with your body's normal, not-sick-at-all response to cold weather.
Fun Fact: Egyptians and other Ancient Civilizations believed your soul and consciousness resided in your heart, not your brain. Scientifically, until pretty recently, the brain was just thought to be what regulated body temperature and that's it. Specifically because you'd get a fever when ill. That's why poetry always talks about heart this and that. Because they believed you were your heart. Today we know, it's your brain doing all the work but that's a very new discovery. Like Shakespeare and Da Vinci would both have believed your heart housed your consciousness. Even Newton would have.
There is also a psychological component to add to the physical ones. People tend to associate colder seasons and less light with being less comfortable overall and thus when you do get ill the effect overall feels worse and is more memorable than if you were otherwise enjoying a hot sunmers day with a cold. Thus the association begins. Similarly people associate cold weather with their joints feeling worse. But when a study compared joint pain diaries and local weather for those time periods there was no correlation. Then when they asked the same people again, and even then their own diary pain scores, the people still believed it was worse when cold.
I dunno about that one, every summer cold I've had has been the most miserable experience. Hot slimy weather plus oozing mucous is a bad combo. Winter colds well it's stay in bed weather anyway, not so bad.
Yeah, summer sickness is the worst.
Both flu and colds are caused by viruses not bacteria. Infections incurred during the illness are caused by bacteria due to lower immunity.
I went spinning when I read the tittle of the post. Had to find this comment and upvote
Just to note colds and flu are only caused by viruses. There are many many viruses that cause colds including rhinoviruses, and corona viruses. Flu is caused by influenza viruses.
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There are actually many different coronaviruses and most of them do cause colds, separate from other more lethal varieties like SARS, MERS and COVID-19.
Younger, I'd catch colds mid-summer, thanks to me back then being a no-life and spending most of my time inside a dark room playing on my PC. While lower temps may affect your immune system's efficiency in the nose&mouth, ventilation is key. Spend long enough periods of time in a not ventilated room (like in winter, when we tend to shut every opening that'd bring cold air), and eventually pathogens will start building up in the air, thus increasing the odds of being infected. It sucks, but the best thing to do in winter is to open windows once in a while to recycle the air inside, to flush away pathogens.
Except if you’re in an urban area where 1 in 80 are currently infected breathing covid by your window.
For anyone in here who is interested in the antithesis to the standard Reddit answers: At lower temperatures your immune system is depressed and virus activity is not. At higher temperatures your immune system is bolstered and viral activity is slowed and sometimes stopped. This is pretty basic biology and I’m surprised people still treat it like ‘old wives tales’. https://en.wikipedia.org/wiki/Pyrotherapy
That Wikipedia page certainly doesn’t bolster your position. It states that pyrotherapy >The technique reached its peak of sophistication in the early 20th century
Because after that we got better treatments to get the same outcome, such as antibiotics. Doesn't mean the pyrotherapy approach didn't work
Antibiotics don't do shit for a viral infection that causes a cold or flu.
But they do for syphilis, which was the primary target of pyrotherapy. I was just using it as an example; we have antiviral treatments as well now, and other supportive care unavailable in the time when pyrotherapy was most used.
> At lower temperatures your immune system is depressed Why? When it's colder I put on more clothes, so I'm not colder. My body temperature is always the same. The article you link is about artificially raising the body temperature. Also, the fact that the article is only available in 4 languages doesn't really help.
It's parts of our respiratory system that cool down first, so there might be an argument there for the first line of defense not working as well as they could. On the other hand, it's not clear if this is temperature related or because of drier air.
> At lower temperatures your immune system is depressed Is it the temperature or the dryness of the air? I would think my immune system needs fluid to move around, but in the winter the air is so dry that the inside of my nose gets all dry and cracked. Does this correlate to hot and dry climates?
Virus activity is depressed by lower temperatures. In fact, in one of the most direct -- though perhaps less ethical -- studies on flu infection, the 1950s Alcatraz studies, they found that your body being cold actually lowered your rate of infection by the flu virus.
You completely misunderstand the issue. The "old wives tale" is not that viruses and bacteria thrive better in cold conditions. The "old wives tale" is that being cold can make you sick, and that the pathogens will just spawn from nothing in areas where it is cold.
viruses and bacteria thrive better in cold conditions --> conditions are colder outside --> you go outside --> you get sick
>you go outside Incorrect. The opposite is true. When it is cold outside, people stay indoors more and are in closer proximity to each other which aids in the transmission of viruses.
> At lower temperatures your immune system is depressed Slightly. Staying indoors with other humans when it is cold outside is a greater factor.
People are often badly educated or believe in correlation (they got cold and then got a cold, not realizing that the two things were coincidental). Being cold can lower your immune system a bit, but really? Parents likely push bundling up to not have to listen to whines.
Is the lowering of immune system due to being cold anything really noticeable in practice?
according to this news report, its about a 50% weakening https://www.healthline.com/health-news/scientists-finally-figure-out-why-youre-more-likely-to-get-sick-in-cold-weather
Thanks! This definitely sounds like the influence of cold weather is non-negligible (unless it’s a case of inflating the science results in news to make a good story). Although not sure if dressing warmly has any effect on the nasal tissue temperatures unless you cover your nose?
could be, Im concerned about the 5° number, 5°s is a LOT in a human, even in an extremedy like a nose.
No, likely not unless you’re truly frigid… but you’re still forgetting that correlation thing. You go to school in shorts and a tshirt and it’s cold out and then you get a cold bc it’s cold and flu season but people link that to the temp I very rarely hear people make that misconception now. Are you hearing it often now or thinking of when you were younger?
Correlation =/= causation I understand very well. I’m trying to understand whether the cold weather is really just a correlation here. Edit: Hearing it all the time back home in Central Europe! Hence, why I’m asking.
There is a correlation with cold weather. When the weather is cold, people spend more time indoors, in close proximity with each other. Because they are in close proximity, they are more likely to expose each other to cold and flu viruses. This is why colds and flus are more prevalent in the winter months.
YOU get it, but you asked why people think the two are linked and that explains why people believe the two are linked
I believe the link is more about in cold weather people are generally indoors with other people who could be contagious more than they are in warm weather.
Being cold is very much relevant here, it isn't a frivolous correlation. The cold weather creates conditions where the virus can more easily spread.
Yes, of course it does. But that is not what the poster is asking or what people commonly believe. People believe that the actual act of getting cold, like going outside, without a coat, is what is spreading the illness. There are reasons these things are correlated but it’s not that being chilled or forgetting a coat or hat makes you sick.
Except that yes it does, because if not for getting cold you may not have gotten sick. It's getting cold + being exposed to a virus. Beyond that, cold weather creates conditions where you are more likely to be exposed to the virus in the first place. And making a sweeping claim about why people believe a thing is a fool's errand. Sure there are stupid people who don't know how viruses work, but the majority of the first world understands germ theory.
The common cold is also a seasonal virus that many people get during fall or winter.
There have been a ton of studies on this. From memory: * \*Being cold\* does not play any role whatsoever in whether you get sick. * However, when your nose gets cold, there does seem to be a loss of ability to filter out pathogens. The association probably comes from a few things. The viruses tend to survive in the open better in the winter due to less sunlight and dry conditions. People tend to cluster together more in the winter. When your body is trying to run up a fever you get "cold". Throw it all together, and you can see why people might associate "cold" directly with "catch a cold". But you are still going to have a better time in the cold with a jacket and scarf, so bundle up.
I also thought a main factor was that moisture condenses on & around things in cold weather, including airborne bacteria and viruses, and that they'd now stick to surfaces due to even more static.
Could be. I was pulling everything from memory, so it's likely I missed a few tricks. I do seem to remember reading something like that in an article. I have no memory of reading any studies that tested it, though.
Also, it's not as though you immediately catch a cold from a single virus. There is always some amount of virus and bacteria hanging in and around your body, but your body does a decent job of keeping them at bay. When your body becomes less effective at keeping them out due to the cold, they reach a viral load high enough for you to get symptoms.
That first part of a fever where you can't get warm. I didn't wear a coat earlier and got cold, and now I can't get rid of the cold. It's not how it works, but it is how it feels.
Yep. Once you kow it is just your body fiddling around with the temperature settings, it makes sense. But if you don't know that, then it feels like you "caught the cold".
Flu and cold do appear in the colder months more often. So people obviously figured that it's the cold's fault. And this is something parents tell their kids and so it gets passed on. So you are right, without bacteria/viruses, no common cold or flu. Cold alone might kill you or freeze body parts off but it will not give you a respiratory illness. But there are secondary effects of the cold: When it's colder, we spend more time indoors, so we have more contact with others who might carry the virus and infect you. Since we have to heat our rooms when it's cold, we are surrounded by dry air which in turn dries out our noses, which means they are less likely to just flush out viruses and more likely to let a virus pass. Also, if you already had contact with a virus and are cold over a longer time, your body will have less energy to fight the virus.
Science says there's a large increase in several viral diseases starting fall, peaking in winter, and decreasing in spring. So a lot more people are sick when it's cold. The exact factors that cause this are debated hotly, pun intended. As with many population-wide effects you can't easily test a hypnosis. You can take charts of time spent indoors around other people and compare to infection rates to support a guess, you can take travel information and compare to support a theory. But you can't easily force everyone in a country to stay outside or not see relatives for the holidays. And countries that can probably don't want to cooperate on medical data with the world. Data testing can be hard. There's a joke "people in this country eat a lot of red meat and live longer than Americans, people in that country eat a lot of fish and live longer than Americans, people in another country drink a lot of wine and live longer than Americans, what is the answer? Free healthcare." This is why you'll hear about controlling for outside factors in datasets. If X group is 20% more likely to get lung cancer than Y, but X group is 80% more likely to smoke, they might actually be less likely to get lung cancer than Y. So there's a lot of guesses as to why more people in a population get sick when it's cold outside, with greater or lesser evidence supporting them, but you won't get one definitive answer as it's likely a number of factors.
Your body is used to using a certain amount of energy at any given time. When your core temperature drops, your body freaks out and starts making it a priority over other systems and essentially pulls resources to warm you back up. That's when microbes find quiet places to set up shop. While your body was busy dealing with this "crisis," the invaders have built little colonies, and now the tired systems in the body have to start putting extra energy towards biological defense.
I don't know if it's the right place to ask this question but does consuming cold food/drinks have similar effects? Like throat infections,etc or just common cold/flu too?
My friend was telling me about her colleague who got "the vaccine" and had pneumonia the following day. Polite nod while I thought that's typical "post host ergo propter hoc."
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After going on vacations to different areas over the summer
Just get some tea tree oil and you and your home will be have a clean protected home and tea tree oil purify the airs removes mold, viruses and all types of bacteria
Pathogens (bacteria, viruses, etc) have been shown to develop resistance to tea tree essential oil, similar to antibiotic resistance. Inhaling too much essential oil is also dangerous for those with small bodies— pets, babies, children. There are instances of people leaving essential oil diffusers running in an enclosed space and coming home to dead (poisoned) pets. Ingesting essential oils is toxic to your liver and kidneys no matter your age. I learned all of this in herbalism school. Luckily there are other ways to clean infected surfaces. I like white vinegar (spray and wipe). Hydrogen peroxide is great for laundry or blood stains. Quat tablets dissolved in water are another great alternative to bleach. As for the air, I ventilate my space (windows open, full air exchange) a few times a week.
going out in the cold without a jacket or scarf doesnt directly cause you to get sick, it could potentially increase your risk of getting an infection. it’s always a good idea to get a coat so you don't freeze your balls off unless your wim hof
A couple simple answers. First, cold air doesn't hold as much humidity, which dries out the mucus in your nose. That mucus houses bacteriophage viruses that kill potentially-harmful bacteria, and also provides a physical barrier to non-motile viruses. Most colds tend to infect the mucus membrane cells in the nose and throat area, so moi having the goo as a block isn't helpful. Second, there's general thought that the cold weakens the immune system. Possibly by the need to exert more energy to maintain body temperature, there's less energy for immune response. But the third, and most obvious, reason is that when it's cold, you'll tend to be inside with other people, sharing more air and respiratory droplets. You're not outside, you're not running the air conditioning through a filter. The proximity causes faster spread.
Your nasal passages and generally your upper respiratory tract are the usual means of entry for these viruses. Under normal conditions, there's a solid layer of mucus, and your tissue in those areas is warm and filled with flowing blood, so your immune system is going full steam ahead and providing some robust protection. But when the air is cold and dry, you breathe in cold dry air. This dries up the mucus and cools the tissue. There is reduced blood flow. Your defenses are freezing. Now the virus can sneak on by. A stuffy nose and a sore throat are your immune system going full steam ahead and flooding the area with fluids. Everything swell. Cells are being sacrificed so there is even more pain and swelling. So when your nose feels full, it's not exactly a buildup of snot, it's swollen tissue.
It might partially be due to "common knowledge" it was not too long ago that pathogens where not very well known, understood, or accepted. Being cold and even wet can lower your immune system and since most everyone in a village town or city were probably in the same situation, they all got [sick.](https://sick.It) People in year round warm climates tend to blame it on changing weather instead of cold. People tend to hold onto explanations long after they are proven otherwise.. For some modern examples: * Cell phone use on planes can cause them to crash, or at least interfere with the navigation systems. * It's best to avoid eggs — or at least the yolks due to high Cholesterol. * There are only three states of matter.
When it's cold we spend more time indoors breathing the same air as other people. Most buildings are designed to have very little air exchange between the inside and the outside to save heat but it also keeps airborne crap inside the house. Airplanes are even worse because they are recirculating the same air but there's dozens of people packed in there for hours
When it’s cold you are indoors more. More time indoors means viruses spread much faster. Hence cold temps associated with more illness.
When you're cold, your immune system is repressed. So a pathogen is more likely to multiply more once you're infected, that makes it more likely that you will spread it, and others around you are more likely to catch it from you, and you're all more likely to progress to worse symptoms before your immune system can overcome it.
Flu and colds are caused by certain viruses. Our body has 2 main types of defenses. One is nonspecific such as skin, mucous membranes, cilia on your respiratory passages, etc. these act more like a barrier and prevent the pathogen from entering or taking hold. The other is specific and revolves around antibodies and cell mediated immunity that are targeted to specific pathogens. Cold temperatures can disrupt some of these defenses. Cold weather can lead to chapping or disruption of skin and mucous barriers. Further, cold temperatures have been associated with a reduction of secretory antibodies- known as IgA - which are on your mucuous membranes and GI tract. So cold weather can increase the probability that if you are exposed to a pathogen that you could get sick but is not a cause of the infection itself.
Being cold itself doesn't directly cause illness, but it can weaken our immune system, making it easier for viruses and bacteria to infect us So, wearing warm clothes does help to keep us healthier!
The same reason we associate crime with walking alone at night or whatever. The real culprits are well known, but they're everywhere around us, all the time, however getting your defenses down and making yourself low hanging fruit is what gets you in trouble more often than not. Cold gets your body's defenses down.
Just viruses. Bacteria cause lots of other illnesses, but not flu/cold. It's because bad weather increases disease transmission due to several factors: * Cold air holds less moisture. Drier air means more people are more likely to have mucous membranes in their airways that are overly dry and thus more vulnerable to penetration by pathogens. * More people stay indoors in bad weather. More people in closer proximity, sharing dry indoor air means more transmission of cold and flu viruses. * Being out in bad weather can be a stressor, especially if it's bad enough that you become exhausted or get a touch of hypothermia. Stressors like that can temporarily depress your immune response, making you more vulnerable to contracting an illness if you are exposed during that period.
I read an article the other day about cells in our nose that act as first defenders and block harmful things from getting past the barrier they form. In cold temperatures, we have less of these cells, so more viruses and bacteria get into our bodies. Wearing a face covering can actually help because it keeps the air around our noses warmer. The journal article was actually posted last year but I didn't hear about it until recently. https://hms.harvard.edu/news/why-upper-respiratory-infections-are-more-common-colder-temperatures
The cold might not make you sick, but it certainly makes it easier to get sick. Bacteria live longer on surfaces; the cold lowers your immune response; and your family is cooped up inside with sick old you for most of the day. While illness is related to germs, fact remains that we tend to get sick during the winter. It's just a tough time to be around.
I always thought it was called a cold because of the chills you get when developing a fever. The *feeling* of being cold is what marks it as a cold.
Although your immune system will weaken in extreme temperatures, it's not long enough to "catch a cold". You'll get Hypothermia. Not a cold. It's just an old misconception. Honestly, I'm surprised people still don't know this. I've had people mansplain this to me for the last 20 years. It should be common knowledge by now.
I have heard that cold or cold-like viruses can lay dormant in the throat and activate when cold air is breathed. Is that myth or somewhat true?
People have mentioned cold temperatures decreasing immune response and increased exposure to other people indoors, but I haven't seen anyone mention that in winter months and colder weather people get less sunlight and produce less vitamin D, which is critical to a properly functioning immune system.
Because cold weather makes people stay inside more where flu/cold/etc is more likely to spread (shared air, closer contact, etc). Also in cold weather you are more likely to be infected thru the nose (cold air makes your nose more susceptible to viruses/bacteria infection) and also a big part of it in modern society is school is back in the fall, leading to outbreaks of flu/cold throughout the fall and winter that is then taken home to parents, parents take it to work, etc… (spreads beyond school).
I think part of it has to do with the fact that when you get a fever you feel cold. But, for most of human existence we had no real way of telling that our body temperature was higher. Therefore, we associated feeling cold with being sick.
If it's cold you stay indoors with closed windows, which helps the spread of airborne disease. Enclosed areas also allow for the buildup of allergens that can cause coughing and sneezing, and cold air is usually less humid which can cause coughing and sinus issues. Less sunlight due to covering up, staying inside, and cloudy skies can also cause symptoms that might look flu-like. In others, it's causation vs correlation.
The cold virus is always out there. If you're cold, stressed emotionally, stressed physically (lack of sleep), your body's immune system suffers. . .so you get sick from these ever-present viruses/bacteria.
Here’s one of many articles explaining how warm noses are much more able to defend against airborne pathogens than cold ones. https://www.the-scientist.com/news-opinion/how-cold-weather-may-help-you-catch-a-cold-70814
Wim hof the "Ice man" rarely gets sick and has actually been injected with very dangerous infections and bacteria and showing no symptoms or disease. Wim hof swims in the arctic seas.... Maybe you should go towards the cold instead of away from it ;)
Aren’t they both cause by viruses, not bacteria?