Transcript:

Winter's Unwanted GuestThe Flu virus is spread in a variety of ways and, like an unwelcome guest it can linger. I'm Jim Metzner and this is the Pulse of the Planet.ambience: sneezeMarr: If you cough or sneeze into your hand and then you shake someone else's hand, the virus can be passed to their hands. And then if they touch their nose or eyes or mouth, they can get it into their body. Another way is it can be transmitted through the air by a cough or sneeze or even just breathing and I'm sick, I may be releasing flu viruses into the air. Those can float around and then there's a chance that someone else could breathe it in and get the flu that way.Lindsay Marr is the Charles P. Lunsford professor of civil and environmental engineering at Virginia Tech.Marr: Under some conditions, the flu virus can survive for many hours in the air and in droplets on surfaces. We found that the survival depends on humidity, whether the air is very dry or maybe more moist. It can also depend on the type of surface that it lands on. It can depend on if you're outdoors. Solar radiation seems to inactivate the virus.If someone in your house has the flu it's probably winter time. That's when we see most of our flu cases and we use heat during the winter time because it's very cold. This makes our humidity indoors pretty low. And we know the virus survives pretty well under those conditions. We know that the virus survives less well, so it kind of gets killed off or is not able to infect people at more medium range humidities. So if you were to run a humidifier, for example, in your house, when someone is sick, you might reduce the chances of other people getting the flu. But we're still working on this question. I can't say with 100% certainty that that's the case, but that's what our research suggests.Pulse of the Planet is made possible in part by the Center for Earth and Environmental Nanotechnology and the National Science Foundation. I'm Jim Metzner.