In this week’s installment of Medical Discovery News, UTMB’s Norbert Herzog and David Niesel explain why more people get sick in the colder months. “The two key components are temperature and relative humidity. In the lab, researchers looked at how temperature and humidity affected transmission of the flu from infected to uninfected animals. What they saw is that, at room temperature, or 68 degrees Fahrenheit, influenza was transmitted the best at 50 percent humidity or less. But when they raised the humidity to 80 percent, there was no transmission of the virus. The highest rate of transmission occurred when they lowered the temperature to a chilly 41 degrees, with a humidity of 50 percent or less. But just by turning up the temperature to 86 degrees, no virus was transmitted. So this means the flu virus transmits best at both a low temperature and a low relative humidity.” MDN airs locally at 10 a.m. every Saturday on KUHF-FM.