Dry air might boost flu transmission

Germs prefer an environment that’s cool, dry and UV-free

For flu germs, warm muggy weather is simply too close for comfort. It saps their vigor, cutting the period in which they remain infectious, according to a pair of new studies.

Although it remains a mystery why flu viruses are so sensitive to heat and humidity, both papers highlight conditions that can aid and abet infection — factors that might be thwarted by controlling aspects of the indoor environment.