Microbiologist Shares Photos That Show How Effective Masks Are At Stopping Coronavirus Spread

A microbiologist has shared a set of photos which demonstrate just how important it is to wear a face mask when it comes to stopping the spread of the coronavirus.

On his Twitter account, Dr Richard Davis posted photos of an experiment he conducted to show precisely what the effects of wearing a face mask are and how well they prevent the spread of germs.

"What does a mask do?" he wrote. "Blocks respiratory droplets coming from your mouth and throat. Two simple demos: First I sneezed, sang, talked & coughed toward an agar culture plate with or without a mask.

"Bacteria colonies show where droplets landed. A mask blocks virtually all of them."

The contrast between photos is, as you can see, huge. In the UK, it is mandatory to wear a face mask or face covering on public transport.

The government has also advised that people should wear them in places and situations where it isn't possible to distance themselves from others, though that's not enforced by law.

Dr Richard Davis

Dr Davis's experiment also took into account the effects and benefits of social distancing - both with and without a mask - by conducting a similar experiment to demonstrating the reduction in spreading bacteria if you're standing the recommended 2 metres away from another person.

For this second demonstration, Dr Davis opened a set of bacteria culture plates and coughed hard for 15 seconds from three different distances - 0.6 metres (2ft), 1.2 metres (4ft) and 1.8 metres (6ft), both with and without a mask.

Dr Richard Davis

"As seen by the number of bacteria colonies," he said, "droplets mostly landed <6 ft, but a mask blocked nearly all of them."

Dr Davis added that while he was aware his demonstration isn't how you would traditional culture viruses or model the spread of the coronavirus, it showed the effectiveness of face masks and coverings in stopping the spread of coronavirus.

"I'm aware that this simple (n=1) demo isn't how you culture viruses or model spread of SARS-CoV-2," he wrote on Twitter. "But colonies of normal bacteria from my mouth/throat show the spread of large respiratory droplets, like the kind we think mostly spread #COVID19, and how a mask can block them!"

Topics: Science, Coronavirus

Mischa Pearlmen

Mischa is a freelance journalist usually based in either New York or London. He has written for Kerrang!, Record Collector, NME, the New York Observer and FLOOD magazine, among others. Contact him at [email protected]