Thread by @andrewjtagg

Is farting an aerosol-generating procedure?

A tweetorial…

When I was researching this article on aerosol-generating procedures the question just popped into my mind.

dontforgetthebubbles.com/aerosol-genera…

And it seems like a lot of you wanted to know the answer too.

As someone who has done some odd things in the name of science, I felt uniquely qualified to get to the bottom of it if @xandvt and @DoctorChrisVT weren't going to do it.

Farts, guffs, parps, a gentleman’s woof - we all do them.

Even the Queen!

So, can the bottom-based emissions of someone with coronavirus be silent and deadly?

That is the question I set out to answer. As you may imagine there is not a great deal of research in this area.

If you look way, way back, to 569 BCE, you might discover that, according to Herodotus, a poorly timed fart from Amasis, messenger to King Apries of Egypt, started a revolution that led to the death of 10,000 men.

mentalfloss.com/article/71138/…

Flash forward almost 2000 years to one of the first great pandemics - the bubonic plague - responsible for the death of up to 200 million people.

It was thought that sniffing one's own farts might save you from the toxic miasma. Breathing in a toxic humor as dangerous as the Black Death itself was thought to be a cure.

And so farts in a jar were born.

They have also been used as a weapon as depicted in the He-Gassen scrolls of the Edo period. These were the epic 'fart battles'

You can see them in all their glory here at the museum website

wul.waseda.ac.jp/kotenseki/html…

We produce about a 1 litre of gas a day (plus or minus 500mls) and release it in 15-20 discrete episodes

ncbi.nlm.nih.gov/pmc/articles/P…

Whilst it might seem to come unbidden to most, the art of the flatulist, first ascribed to Le Pétomane, involves contraction of the abdominal muscles and a forced indrawing of air through the rectum.

Here he is in 1900, as filmed by Edison

Here, a modern practitioner of the (f)art, Mr. Methane (@mrmethane), demonstrates just exactly why it is called wind.

gfycat.com/tartabsolutebl…

Though it is possible that it is just a load of hot air as these thermal imaging cameras suggest

So farts CAN have the power to spray talc long distances. And, in terms of size, a particle of talcum powder is 5 times bigger than a 5-micron aerosol droplet.

ncbi.nlm.nih.gov/pubmed/29261577

What has all this farting talk got to do with the coronavirus?

Well, SARS-CoV-2 can be detected in faeces and has been detected in an asymptomatic individual up to 17 days post-exposure.

wwwnc.cdc.gov/eid/article/26…

This asymptomatic carriage has been replicated in a number of studies.

thelancet.com/journals/langa…

So what is the answer? As with a lot of science, we just don’t know.

In fact, the only paper I could find was this one by the illustrious @DoctorKarl

ncbi.nlm.nih.gov/pmc/articles/P…

Dr. K and Luke Tennant volunteered to fart on a petri dish.

There was no growth when the fart was filtered by trousers but with no barrier between agar and arse gut flora proliferated.

Perhaps SARS-CoV-2 can be spread thought the power of parping - we need more evidence. So remember to wear appropriate PPE at all times and stay safe!

~The End