It Only Takes a Few Hours for Viruses to Spread Everywhere

In just two to four hours, virus contamination on a single doorknob can spread throughout a room, researchers report.

In new research presented at the 54th Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC), scientists used the virus type bacteriophage MS-2 to stand in for human norovirus, which is the common cause of the stomach flu. They placed some of the virus on a door knob or a table top at the beginning of the day in office buildings, a conference room and a health care facility.

Then they waited.

At various points in the day, they sampled 60 to 100 different surfaces like railings, countertops, phones, computers and coffee pots–all of which can carry infections. They found that within two to four hours, about 40 to 60% of the surfaces they sampled had the virus.

That’s not great news as we creep closer to flu season, but the researchers also found that by using disinfectant wipes with quaternary ammonium compounds (there are 90 different approved formulations) and washing hands, the virus spread was lowered by 80 to 99%.

Now that’s a good argument for keeping up the hand hygiene.

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