Just one germ-laden doorknob can infect entire building in hours, study says

The way in for viruses? (AP Photo/Susan Montoya Bryan)

"The hand is quicker than the sneeze in the spread of disease," warns the lead author of a study that found a single germ-laden doorknob can spread a virus throughout a building in the space of hours.

University of Arizona researcher Charles Gerba's team placed a harmless virus with similar properties to the stomach flu-causing norovirus on surfaces like doorknobs and tabletops and found that 40% to 60% of people in the same building had the virus on their hands within a few hours, CBS reports.

The virus could also be found on surfaces throughout the building and was especially prevalent in break rooms. "We actually put a virus on a push plate in an office building of 80 people, had three entrances, and within four hours it ended up on over half the people's hands, and it ended up on over half the surfaces that people touched in that building," Gerba told the 54th Interscience Conference on Antimicrobial Agents and Chemotherapy earlier this week, reports the Washington Post.

Norovirus is behind 20 million illnesses in the US every year, often through infections caused by people touching contaminated surfaces and then their faces, but the researchers say hand sanitizers and disinfectant wipes can reduce virus spread by up to 99%.

(One Canadian city has replaced doorknobs with levers—but not for hygiene reasons.)