Colder, drier climates are ideal for a flu outbreak.
There are many theories as to why the flu is particularly aggressive in the wintertime, but none more pervasive than the idea that the cold is responsible for causing the flu. This, however, is scientifically proven false. While the idea that the cold causes the flu seems to make sense as flu season coincides with the arrival of the cold months, it is, in fact, the presence of the flu virus that causes the illness, and not the temperature. This was proven in the 1930s, when scientists could isolate the virus from humans, tagging it as pathogenic. It is true, however, that the exceedingly low temperatures create an ideal environment for the virus to circulate.
A paper from the 1960s proved this when the study above tested the survival times of different viruses. How? At different temperatures and levels of humidity. It concluded that the influenza virus thrives at low temperatures and humidity levels. The virus studied in the experiment was able to survive for over 23 hours at 43 degrees and with relatively low humidity. In contrast, its survival time of only an hour at a temperature of 90 degrees and with high humidity. This was backed up by a third study that showed high rates of infection following an arid period. It proves once and for all that cold, dry climates are the influenza virus’ playground.