Coronavirus: Once you've washed your hands, how you dry them matters too

Next time you're faced with a choice between using paper towels and a hand dryer, go old-school. 

New research has found people who use air dryers can end up with 10 times as many viruses left on their hands than those who use paper towels.

"We believe that our results are relevant to the control of the novel coronavirus that is spreading at pace worldwide," researchers from the Leeds Teaching Hospitals NHS Trust in the UK said.

"Paper towels should be the preferred way to dry hands after washing and so reduce the risk of virus contamination and spread."

Health experts say washing hands is one of the key ways to avoid contracting COVID-19, which has killed about 150,000 people worldwide this year. It enters through the mouth, nose and eyes, which people frequently touch with their hands. 

While soap is effective against the virus, it doesn't always kill all of them - and not everyone bothers to use soap.

In an experiment, volunteers' hands were contaminated with a harmless virus, but not washed properly - instead, the volunteers went straight to drying them off then touching surfaces like handles, lift buttons and phones.

Testing showed surfaces touched after drying with air dryers got infected with the virus, while only six of the 11 surfaces did when volunteers used paper towels. 

Of the surfaces that did get infected after being touched by people using paper towels, there were five to 10 fewer times as much contamination than when people used air dryers. 

Another unlikely way to avoid COVID-19 could be not using banknotes. Researchers in Germany have found the virus is 100 times less likely to survive on coins than notes.

"I believe that the risk of transmission of the virus through money, even banknotes, is far below that of a face-to-face contact with an index person," said Profr Johannes Knobloch of the University Medical Center Hamburg-Eppendorf.

"Regarding the current COVID-19 pandemic, if cash must be used for payment, coins would be better than notes. However, card payment can be performed completely contactless and avoids the risk of carrying cash altogether."

Both studies were revealed at the European Congress on Clinical Microbiology and Infectious Diseases.