Microbiologist’s ‘gross’ face mask test divides internet

A doctor in the US claims this photo shows the difference a face mask can make fighting COVID spread — but not everyone agrees.

As Australia faces a surge in the number of virus cases from an outbreak in Victoria, a scientist has shared why wearing a mask can make a big difference.

In a Twitter thread that has since gone viral, microbiologist Dr Richard Davis has conducted an experiment he claims shows how both wearing a mask and following social distancing can greatly reduce the spread of droplets.

COVID-19 spreads through droplets from infected people, with sneezing, breathing heavily and even talking known to spread the virus.

Dr Davis, who is the clinical microbiology lab director at Providence Sacred Heart hospital in the US state of Washington, performed two simple experiments in an effort to prove his point.

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The first test showed the difference wearing a mask made doing everyday things.

In his first demonstration Dr Davis sneezed, sung for one minute, talked for one minute and coughed twice towards an agar culture plate.

He did this twice, once wearing a mask and once without a face covering.

Photos of the plates showed bacteria on all the ones where he didn’t where a mask, while there was minimal spread the times he covered up.

“Bacteria colonies show where droplets landed. A mask blocks virtually all of them,” Dr Davis tweeted.

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The second test showed the difference social distancing made.

In his second demonstration Dr Davis showed how wearing a mask while social distancing can be even more effective at stopping the spread of coronavirus.

He placed different plates two (60cm), four (1.21 metres) and six feet (1.82 metres) away from him and coughed “hard” for 15 seconds.

Incredibly, the mask blocked “nearly all" of the droplets at all three distances while droplets easily landed when the person was two and four feet away and not covering their face.

There was only minimal droplets when a person was six feet or more away.

Dr Davis’ tweet got thousands of retweets and replies, with several saying it was a simple and “gross” way of explaining the benefits of masks.

This is my obligatory Wear. A. Mask. tweet.

While we're at it keep that distance. https://t.co/IQt0AIswSx

— Gina Miller😷 (@TheGinaMiller) June 29, 2020

PLEASE wear a mask so we can put this behind us. Wear it for your friends and family and neighbors. Wear it so you can go back to doing the things you love much.
The same people complaining about things closing back down again are the same people not wearing masks. #WearAmask 🙏🏻 https://t.co/2dTtZSSCk8

— Lauren Summer (@HeyLaurenSummer) July 1, 2020

But not everyone was convinced, with some claiming there was no way of knowing the results weren’t a once-off, arguing they just pointed to the importance of keeping a distance from others.

So it proves that even without a mask 😷 at 6 feet there is very low probability of transmission https://t.co/SwuJ9B5TxG

— Steve Villarreal (@ssvme) July 1, 2020

Love this, but the sad part is it won’t change their minds. We get excited about the power of science to prove things. While the deniers will deny and make excuses.

— U ain’t Puerto Rican (@MakoResists) June 29, 2020

This proves that masks are not needed. Talking and singing even face to face just 1 foot away provided the same bacteria culture as when masked.

Time to end the mask paranoia and reduce the distancing requirement to 3ft distancing for talking.

— Hugh (@HughLesman) June 28, 2020

In response Dr Davis tweeted that while his “simple” demonstration wasn’t specifically based on how coronavirus spread it showed how “colonies of normal bacteria” — which would contain COVID-19 if you were infected — would mostly spread through “large respiratory droplets”.

He said that viewing masks as a “political/social litmus test” was a “travesty”.

In the US the wearing of masks have become a hot-button issue, with President Donald Trump and many of his supporters refusing to wear them despite many states making it mandatory to do so when out in public.

“We wash hands after using the bathroom & wipe noses on tissues. Masks/face shields need to be just another normalised act of hygiene,” Dr Davis tweeted.

I try to be really clear what this does & does not show.

DOES SHOW: the act of talking (or coughing, sneezing, singing) causes particles of liquid to come out of your mouth.

DOES SHOW: those droplets can carry microbes like bacteria

DOES SHOW: a mask blocks most of those

— Rich Davis, PhD, D(ABMM), MLS 🦠🔬🧫 (@richdavisphd) June 27, 2020

DOES NOT SHOW: what is the number, size, and distribution of respiratory droplets produced by coughing/talking etc.

DOES NOT SHOW: could these droplets carry viruses (like SARS-CoV-2), does a mask block THOSE

(Based on what we know you can intuit/infer this, but it's not shown)

— Rich Davis, PhD, D(ABMM), MLS 🦠🔬🧫 (@richdavisphd) June 27, 2020

MASK WEARING COULD BECOME MANDATORY

Unlike other countries, Australians have not been advised to wear masks, with fears it could lead to people becoming complacent about handwashing and social distancing.

This comes despite the World Health Organisation revising its advice around mask, saying they should be compulsory in places where there is widespread transmission.

On Tuesday Australian Health Minister Greg Hunt said that the wearing of masks could be strongly encouraged or even made mandatory in places where there are coronavirus outbreaks.

“If there is a community outbreak then state and territory authorities are in a position to make decisions on whether this should be encouraged or mandatory. This is one of the items Victoria is looking at,” Mr Hunt said.

Federal Health Minister Greg Hunt said masks could become mandatory in outbreak areas. Picture: AAP Image/James Ross.

Victoria’s chief health officer Brett Sutton told the ABC that he has “a team working up some advice now” on the issue.

The state is in the grip of a coronavirus outbreak in Melbourne after several security guards at quarantine hotels caught the virus.

“We will talk about masks in those types of settings for people to choose it and provide some guidance on the masks that work and how much protection you get,” he said.

“I take the perspective that when you are really trying to drive numbers down to maintain your test and trace capability, it (wearing masks) needs to be considered.”