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Researchers Explain Why Flu Comes In the Winter
First time accepted submitter ggrocca writes "Using human mucus as a testbed for how well influenza virus thrives in different humidity conditions, researchers at Virginia Tech found that the virus survived best if humidity is below 50%, a typical indoor situation during the winter in temperate climates due to artificial heating. The virus begins to find itself at home again only when humidity reaches almost 100%. Unsurprisingly, the latter finding explains flu spikes during rainy season in tropical climates. Full paper on PLOS ONE."
But influenza is not exactly something new. Why is this a new discovery?
First sneeze
rewriting history since 2109
Where does Madagascar fit in that theory?
I have asked this question for years without a satisfactory response. Finally, a scientific answer!
wait, the virus survives best @ 50% humidity and less - but the virus feels at home @ nearly 100% humidity? does not compute
Just because central heating drives down the relative humidity to 50% indoors doesn't mean it's not also near 100% outdoors, where colder temperatures give much higher relative humidity for the same humidity ratio.
Very silly. When it's humid outside, it's humid inside.
Feb 2009 article found the same thing:
http://articles.cnn.com/2009-02-11/health/healthmag.humidifier.flu_1_humidity-water-vapor-winter-flu-season?_s=PM:HEALTH
In Phoenix, relative humidity is below 50% on average from April thru September. In Albuquerque, it's March through June. Does flu hold out year round in those areas?
The virus is around year round. However, in the winter you stay inside and get less sunlight...thus less vitamin D.
Doctors destroy health, lawyers destroy justice, universities destroy knowledge, religion destroys spirituality
The cold windows do.
I always figured schools were a big part of it. Pack 25-35 kids in a classroom. Reshuffle the kids 6 to 8 times per day. It's an ideal environment for spreading any contagious disease.
So are airplanes.
the fact that when it's cold outside, more people are inside, especially communal indoor places like malls, food halls, etc. A more efficient route of transfer?
My wife *knows* it is caused by exposure to cold weather :)
I work outside year round with a week or two off when its really cold. (below 20 F). I hardly ever get sick. Yes I'll get head colds runny nose and maybe a light cough but who doesn't when the weather is changing. but as far a s the flu. almost never. I can only think of twice in the last 17 years and the firs time I still worked.
"Drive Fast Kill Slow"
Typical indoor HVAC design conditions: Summer - 75F / 50% RH, Winter - 70F / 30% RH. So indoors I would think the virus would survive well year round, just better during winter.
Outdoors the air temperature might swing 20-30F between the day and night. This is going to swing the RH levels in an even wider range - maybe between 20% and 80% depending on season, time of day, local climate etc.
I would think the virus survival would correlate better with time periods when there isn't much change in the outdoor air temperature/humidity levels for several days during winter, rather than anything with indoor conditions.
In winter, people make little to no vitamin D: http://en.wikipedia.org/wiki/Vitamin_D_and_influenza
Even in places near the equator, if people stay indoors to avoid rain, they will have lower vitamin D levels, unless they supplement.
A 21st century issue: the irony of technologies of abundance in the hands of those still thinking in terms of scarcity.
http://www.drfuhrman.com/shop/super_immunity_book.aspx
Things to be aware of that he would mention:
* vitamin D deficiency
* iodine deficiency
* B-complex deficiency
* omega-3s deficiency
* eat a lot of vegetables, fruits, and beans, and some nuts, seeds, and whole grains
* avoid refined sugars and grains
* avoid food additives (artificial colors, artificial flavors, most preservatives)
Many vegans and vegetarians eat a refined starch-heavy diet with too little vegetables and so are sicker than meat-eaters who also eat a lot of veggies.
In the case of influenza, a lot of it is probably due to vitamin D deficiency in the winter, whether from the Earth's tilt relative to the sun or from cloudy weather and stay indoors in rainy season near the Equator. People probably generally eat less vegetables in winter, too.
A 21st century issue: the irony of technologies of abundance in the hands of those still thinking in terms of scarcity.
There is a major flaw in the study. First it states that the flu virus thrives in humidity conditions below 50% which explains why in the winter we have these outbreaks. However, with modern heating and cooling systems, indoor humidity levels are almost always below 50%. At 55% is where mold begins to grow, so unless your home or office is damp enough to grow mold, chances are that year round you are at 50% or less humidity, not just during the winter.
The other flaw is that the researchers point out that the humidity needs to be low as in a room with "...really heated air..." so that the mucos droplets evaporates leaving the virus to float freely. That is not going to be your typical living space, because if it is hot enough to be evaporating mucus droplets in the air then it is either really hot (85 deg F or greater) or really dry, less than 25% humidity, which would mean that most people would be having nosebleeds and other problems.
So, while the research may be accurate on the zones that the virus does best in, it does not actually translate into the environments we live in and explain the outbreaks we see.
"...the winter in temperate climates due to artificial heating."
Is anyone else missing the lower humidity we generally have in the winter -outside- in temperate climates due to it, you know, being cold?
Said to me, today actually, cuz she have a "common flu" at this moment, is that usually she gets it in "cool season". Which means from December till February/March.
Raining season or hot season, no problems. But cool season*... problems.
*= Cool .. 33 at day 22-25 at night, low humidity.
It really doesn't tell me why does the federal government puts out flu. Population control. We need real research into that.
Never ever touch your eyes or nose, wash your hands often and you will very likely avoid getting the flu.
By the way, the overall conditions of winter (cold weather outside, dry air inside) make people much more likely to touch their eyes and nose. Observe people in hospital even at the peak of the flu season and you will see them sooner or later touch their face while waiting.
Here is Arduino based project to control humidity in apartment.
Not really I could have drainage witch
Is a "drainage witch" anything like a Ditch Witch?
I suspect that the body getting cold lowers resistance. The other reason is that they purposely release these flus to make us sick.
Is it one of these things?
I bought four of them a few years ago. They don't go below 16%. They also differ in their opinions of the humidity by as much as 20%, even when they're all sitting right next to each other. Indeed, one had to be placed in incredibly moist air, otherwise it never displayed anything other than 16%.
What about places such as Wyoming and Colorado that are dry (under 50%) for most of the year?
Also, my family had a hog farm growing up. The hogs were outside exposed to the elements. Every November in the early '80s we got hit with a major influenza outbreak in the hogs approaching 100% among the hogs weighing 60 to 180 lbs. There was no major change in the humidity, and didn't depend on rain or other weather events. Assuming the infection mechanism is similar (and certainly the influenza viruses were similar or the same since hogs are the source of many influenza virus mutations crossing over to humans), how does this result explain this?