Mom was right: You're more likely to catch a cold in the cold

Then, the authors turned to the real question: Why? What is it about rhinoviruses that makes them prefer 33 degrees? Previous research has failed to provide an explanation. There appears to be nothing about the virus itself that makes it favor lower temperatures. So, the authors turned their attention to the host’s immune response. And here, they found their answer.

Mouse cells infected with rhinovirus produce a weak innate immune response at 33 degrees C. The authors discovered that secretion of interferon-beta, a molecule important in the body’s anti-viral response, is much lower at the colder temperature. (See figure.)