Why do we get colds and flu in winter only?

Question

Why do we suddenly get the flu in December. Why do people get more colds in winter.

And does the other half of the world (eg Australia) also get flu at this time of year even though its their summer, or do they have a separate flu season in their winter.

The flu season in this country runs from December till end of Jan. Thats the period that scientists plan for when putting toghether the flu vaccine each year.

Given that viruses spread round the world very quickly given air travel etc. does the southern hemisphere get affected by this same flu in their summer. (if so, do they also give flu vaccines in december).

and if they have a separate flu in their winter (which presumably would be a different strain), why does that flu not also affect us here.

or would the predicted flu pandemic only affect the northern hemisphere?

Answer 1

They are not confined to the winter months. You can get a cold at any time of the year. The flu just hits us when we are most vulenerable...;

Answer 2

The old reason that people used to believe was about us all being stuck indoors or clustered together on public transport during the winter - however this does not make sense - who's boss lets them drag their desk outdoors in the summer months?

We use public transport the same amount in the summer as in the winter and stay in enclosed spaces for the same amount of time as well.

The real reason is the lack of sunlight on our skin. The sunlight triggers the production of B vitamins which help our immune systems. Lack of sunlight means less B vitamins means poorer immune response means more likely to suffer from any passing virus as opposed to fighting it off.

Of course people get summer colds but that is due to other factors. By the way - a heavy cold is not the flu. Influenza is a serious life-threatening illness and has different symptoms.

Take supplements, people!

Answer 3

A cold or flu is caused by a viral infection, and viruses tend to be very contagious. They are spread primarily by droplets, or in other words, by saliva and mucus either sprayed into the air or by direct human contact. Going repeatedly from a cold to a warm environment and back should not increase your chances to become infected. However, when the weather turns colder, people tend to begin spending more time indoors. This creates closer human contact and thereby increases the likelihood of infection. This is in large part why cold and flu season is during the colder months.
xxx

Answer 4

I See the PROBABILITY of Coming In Contact With a Infectious Organism Goes Up, an Organism is More Likely to Spread When People Move Inside.

Answer 5

We can get a cold at any time of year but in the winter the air is colder and therefore the germs/bacteria survive longer so it can be passed on easier. That's why it's easier to get a cold or flu more than once in the winter, just when you think you've gotten over a dose you get sick again. Colder weather in any part of the world increases cold and flu in their winter seasons.

Answer 6

during the winter time, the defences of our body are low. and this is the season in which Rhinoviruses or cold viruses are active due to the weather conditions. Therefore they attack the other organisms and we get cold. well, I don't exactly know about the southern hemisphere, but i think that they usually get cold in the winter too. but there are summer colds too that may last forever.... :-)

Answer 7

Probably because of the colder weather conditions coupled with the dark nights.

The lack of sunlight tends to dampen our spirits, which in turn means that we are producing less 'feel good' vibes (endorphins). This has an effect on our immune system which becomes more susceptible to colds and flu.

I also find that workwise everything seems a lot busier in the winter months ~ more pressure, more stress which also weakens our immune system. Perhaps the worry about Christmas looming affects many of us too.

I'm not sure about Oz. I'm sure someone else will answer that part of your question.

Best wishes.

Answer 8

Although I don't think you do just get colds and flu in winter (I certainly have got summer colds and they are yuk) I see what you're asking. I would imagine it is something to do with the cold, wet, blerghness of the weather combining with the cold germ to make it worse.

Answer 9

We get colds all year round

Answer 10

it is just that it is more noticeable in the winter because we are stuck inside so we concentrate on it more and in the summer we can get out and not notice it