This is a recurring question for many scientists. Researchers in New York have been able to show that the flu virus is ideally transmitted in cold, dry weather.
The flu virus, unlike colds (which is transmitted through contact), is transmitted in the air. If it is too hot, it dies and if it is too wet, it falls like a drop of water.
This is how you can catch the flu from November to March in the northern hemisphere and from May to September in the southern hemisphere. On the other hand in the tropics, there is almost no flu, too hot and too humid!
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