Doctors who use hand sanitiser between patients are more likely to spread flu than those who take the time to wash their hands, an experiment suggests.

Japanese researchers conducted a series of lab and clinical tests to examine how much active influenza A virus remained after exposure to an ethanol-based disinfectant sanitiser compared with handwashing with an antiseptic cleanser.

They dabbed volunteers’ fingers with either mucous or a saline solution containing flu virus, and then tested how long it took to deactivate the virus so it could no longer be spread.

Flu virus in wet mucus from infected patients wasn’t destroyed after two minutes of exposure to sanitiser; it took about four minutes for the virus to be deactivated.