Thread by @jmcrookston

A damning indictment of droplet theory from as long as ago.

1936, Wells & Wells, a husband and wife team.

Thread.

History. Before 1861 we didn't know there were organisms in the air. Just that we got sick. I've posted elsewhere that they knew fresh air was good, but not why.

Some people believed just something about "bad air" (origin of word "malaria" is mala aria from medieval Italian).

Others thought it was from excretions, maybe our sweat or breath.

Wells & Wells (I'll just refer to both as Wells) noted in 1861 we discovered little organisms. Aha.

Forward to the turn of the century, Chapin, a santitation engineer, said let's stop cleaning cities and examine how diseases spread. He examined the various ways, but relevant to us he looked at close contact and long-range airborne (miasma). He liked close contact.

Wells:

At turn of century, close contact dominated.

This article in 1936 notes that no real way to show until recently. Hence, they wrote this article.

They note the two forms.

1. Droplets flying through air and floating particles.

(Wells prefers the latter.

Chapin had preferred the former - although he didn't rule out the latter, as I've said elsewhere.)

2. Small droplets that float.

What we'd call small aerosols these days.

What the epis call "airborne" except they often use that word to only mean "long-range".

Wells noted that the droplets really couldn't infect. They didn't do anything but fly out and fall to the ground. Couldn't explain wide dissemination of pathogens.

The little drops though, could float. That could explain it!

They tested. They aerosolized bacteria and lo and behold, it was found throughout a building.

Including to the upper floors.

Aha! So these little aerosols can really get around.

This confirmed these things were airborne. Wells notes, this might change our understanding of things the way when we discovered cholera in our water we knew to treat it - hence his reference to drinking water.

Ask epi friends about the pump handle story.

This, Wells thought, should answer things. Airborne it is!

Airborne explained intensive outbreaks of measles and smallpox!

No longer would airborne have this burden of proof to meet to show it was how things transmitted!

[Narrator: Little did Wells know how wrong they were]

Tests showed how readily people got reinfected, so it couldn't just be droplets.

But hold on, if it's in the air why don't we see it everywhere?

Because we only see the CLINICAL INFECTIONS. We don't see the people who don't get sick!

(Lots of us have been saying this for a while. High R means infectious not that it alone travels in air.)

Many infections through the air don't lead to sickness. They fall like "seed on stony ground", quote below:

And maybe the reason hospitals aren't chalk full of sick people is that they have better air, or that people were most infectious before they went!

And just to reassure their readers, they pause to note they are not talking about miasma theory. This isn't just bad air randomly floating around.

Nor are they really referring to infection over miles and miles, like pollen.

So, they turn to look at contact:

Contact isn't a good explanation. Droplets fall to ground too quickly, too soon. Not enough time to infect.

Chance of big outbreak with droplets would be small.

BUT if it came out in sneezes that filled a room (aerosols), we'd see these explosive outbreaks, which we do!

And if they could count the subclinical infections they could answer this. But no way to do that.

This makes sense. If you have bacteria who get in through respiratory system you'd expect them to have been acclimatized to getting in and out through that system. They'd be used to life in the air.

Other bacteria would travel in other ways, and might not be airborne.

Sexually transmitted diseases for example transmit by touch, not air.

There are diverse routes, and air is one of them, esp. for respiratory diseases.

They conclude by noting that the diseases society could not control enter and exit the body through the respiratory system.

Those include the most important: flu, pneumonia, tuberculosis.

Ends w/ until the purity of our air can be established we cannot control these diseases.

The article is here: jamanetwork.com/journals/jama/…

Mr. Wells passed away, having passed the torch to his protege Riley who continued to work on air matters.

I am still trying to locate information about his wife Dr. Wells, but she certianly wrote her own articles about measles,etc.

Grr. Of course I made a typo in the very first slide.

@Twitter ! Allow editing already!

*From as long ago as 1936.

One quick correction. I said Chapin was an engineer (that's what I recalled).

I checked his book just now and Chapin was the Superintendent of Health for Providence Rhode Island. But no mention of his credentials, so my comment might not be correct. I'll check when have time.

Ah, a doctor. "Charles Value Chapin, M.D. (January 17, 1856 – January 31, 1941)"

He is also a fascinating read. Pioneered that pathogens live and transmit between hosts instead of throughout the environment. So can study chain of transmission. His book at Internet Archive.

A short tribute article by Riley; about his & Wells' study of tuberculosis. Before it was reported, Wells collapsed, was taken to hospital, and went somewhat mad.

His tech caught tuberculosis.

Answers that Wells' wife had died previously

atsjournals.org/doi/10.1164/aj…