Scientists now have a better understanding of how the flu spreads, and it has a lot to do with the weather forecast. Oregon State University says the key is absolute humidity.
It's long been known that flu spreads better in dry weather. But now we're understanding that we can measure how long it will be around based on how much water is in the air. When absolute humidity is low, the flu virus survives longer and transmission rates go up.
Researchers say the link is very strong. They say this will help scientific and medical communities, because doctors will now be able to forecast the flu's spread more accurately. The findings appear in the journal "Proceedings of the National Academy of Science."