Ever wonder why winter is flu season? Well, scientists finally found the answer:
Experts have long pondered why flu and other respiratory viruses spread more in winter. No one explanation, such as people staying indoors more, or the destructive effect of the sun's radiation in summer, has fully explained it. [...]
Influenza viruses coat themselves in fatty material that hardens and protects them in colder temperatures -- a finding that could explain why winter is the flu season, U.S. researchers reported on Sunday.
This butter-like coating melts in the respiratory tract, allowing the virus to infect cells, the team at the National Institutes of Health found.
"Like an M&M in your mouth, the protective covering melts when it enters the respiratory tract," said Joshua Zimmerberg of the National Institute of Child Health and Human Development (NICHD), who led the study.