People check in and out of hotel rooms but often leave their cold viruses behind for the next guest. Researchers have found that the rhinovirus can survive on surfaces for as long as 24 hours.

In a study to follow the trail of cold transmission, a team from the University of Virginia visited hotel rooms and examined doorknobs, switches, telephones, TV remotes, and just about any imaginable surface that might come in contact with an unwashed hand, searching for signs of the virus.

They found that the virus lingers on more than a third of the objects touched by someone who has a cold. An hour after an infected droplet is deposited by an unwashed hand, it has a 60 percent likelihood of being transmitted to the next person who comes into contact with it.

The researchers noted that the rhinovirus can stick around waiting to infect its next victim as long as 24 hours after being deposited onto a surface, when it might be picked up a third of the time.

Not surprisingly, children are more likely to spread the cold virus than adults, and they are much more likely to catch colds. In the US, children experience colds about seven to 10 times a year, while adults typically have two colds a year.

Hotel rooms tend to be particularly infested with the cold virus, since so many different people use them. The researchers concluded that on average, any frequently handled surface in a hotel room is likely to harbor and spread the cold virus about 50 percent of the time.