The main mistake Western nations are making in the COVID-19 fight is not telling everybody — including healthy people — to wear a face mask, a leading Chinese scientist says.

Dr George Gao (PhD), director-general of the Chinese Centre for Disease Control and Prevention, says taking temperature readings at the entrances of shops and public transport stations to ensure people with a fever stayed out was an important part of China’s response, as was isolating patients in converted sports stadiums.

But healthy people wearing masks was crucial, said the virologist and immunologist.

“The big mistake in the US and Europe, in my opinion, is that people aren’t wearing masks,” he told the journal Science, which reportedly spent two months trying to get an interview with him.