CNN Sanjay Gupta MD December 13, 2014 21:33:00
Can spread it to many people and it can make it seem like more flu going around. because of the season you get less sun light, less vitamin d, you get changes in your immune function overall. finally, there is correlations with the weather but maybe not in the way you think. colder weather, less humid. viruses can live longer if it is less humid. so the virus just stays around longer. those are three reasons why it is more common. it is amazing nobody knows exactly for sure. >> mom may have been...
Source: archive.org