Evidence for airborne spread of Covid-19 is strong, but authorities underemphasize airborne protections. The curious history of infectious disease reveals how this anti-airborne bias emerged.
Great article, but you left out Snow's single strongest piece of evidence. Any comparison of neighborhoods was still in principle at risk for being confounded by different atmospheres. In one neighborhood, however, houses supplied by two different water companies were mixed together on a very fine scale, almost like a random assignment. One company had a source upstream of sewage, the other downstream. You can fill in the rest.
I had more info about Snow in there at one point, but it was just too long! His evidence was good, and he had decades of it. But good point and thank you for reading.
This view of position on the airborne transmission is simply false, and uses a bunch of nice story telling to pass the pill while not citing any evidence.
Moreover, SARS-CoV from 2004 was declared to be transmissible through aerosols, just as well as measles - meaning that a suspension could remain in the air for hours and hours infecting anyone passing through the cloud.
For SARS-CoV-2 specifically, there were early on attempts to see if it could be transmitted by aerosols by experiments where the virus was aerosolized and then the suspension aspirated and checked for the vRNA presence (positive) and possibility to give cultures after aspiration (negative).
There was never a question of aerosolization not being a consensus in the medical community: it was more of a question of usage of language and the scientific publications about it were very clear from the start: https://www.nature.com/articles/d41586-020-00974-w
Hey Andrei thanks for reading and taking the time to comment. I'm not sure what your issue is though. My primary concern is that - in the US in particular - we are not *behaving* as if Covid is an airborne virus.
1. We emphasize ventilation and air filtration very little.
2. We don't have a general mask standard for media and fit, and we do not emphasize fit.
3. We treat plexiglass and six feet of distance as if they somehow prevent transmission.
4. We - companies, schools, etc - advertise how we are sanitizing surfaces, but few invest in other measures that would make a bigger difference.
I don't have any issue with the idea that there's a spectrum of transmission and do agree that much of the problem is about cross-discipline terminology, but lack of public understanding about airborne risk suggests that there is a problem to me. Again, thanks for taking the time to read and provide feedback.
Nice article, but the essence of the story is that science is managed by idiots that dont think for themselfs. Testosterone fuelled balled old men. Anyone who challenges their views is punished untill the evidence becomes overwhelming enough that it cant be denied anymore. Then they will find ways to get the credit for it and say that they knew that all along
This is very nicely written and a great history of epidemiology. However, I'm not convinced by the core thesis.
The idea that viruses can travel long distances in the air is not actually controversial within the field. There are papers exploring "aerobiology" and which investigate the possibility that influenza is spread around the world by the wind. They are obscure but they exist and they were published in recent decades. More surprisingly, Ferguson et al first came to the world's attention during the UK outbreak of foot and mouth disease. The story was the same: their models predicted huge disaster if there wasn't totalitarian state action, in that case, mass killings of farm animals whether they were infected or not. Their recommendation was to destroy entire farms simply because they were downwind of farms that had infections, even if no foot-and-mouth was detected on the farm itself. The models were later invalidated by accidental control cases, but not before funeral pyres of animals filled the skies with smoke.
So I think you are giving public health too much credit as a profession. In your telling they are basically well intentioned but hopelessly conservative to the extent that they ignore evidence they're wrong until they literally die of old age. This conservatism explains their reluctance to consider long range airborne transmission.
The evidence I see when reading modern epidemiology papers is different. If airborne transmission lets them recommend extreme, dramatic state action, they model airborne transmission. If it would undermine the case for totalitarian state action, as it would for lockdowns, then airborne transmission doesn't exist. None of this is tied to microbiological theory: despite what you'd expect, epidemiology is a microbiology free zone.
There's really only one thing that seems to coherently explain public health decisions: they pick whatever "explanation" gives them the most power and doesn't require them to admit mistakes. There's nothing more to it than that. Public health is really one of the most corrupt and dangerous fields I've ever encountered. Their papers are filled with errors and they don't care because they realised they can just stare down politicians and most of the public, regardless of how inconsistent their supposed expertise is with collected data. Mark my words: if someone figures out a way to control people's lives even more through a long range transmissible, airborne virus tomorrow, then the day after tomorrow such a virus will have emerged and be being used as a policy justification. Perspex plates will be immediately forgotten and anyone who remembers them too loudly will be banned for misinformation.
Typo:
"Today each of us breathes in a swimming pool of air every day, and few among us give much though to what’s in the air."
though -> thought
Fixed thank you.
Great article, but you left out Snow's single strongest piece of evidence. Any comparison of neighborhoods was still in principle at risk for being confounded by different atmospheres. In one neighborhood, however, houses supplied by two different water companies were mixed together on a very fine scale, almost like a random assignment. One company had a source upstream of sewage, the other downstream. You can fill in the rest.
I had more info about Snow in there at one point, but it was just too long! His evidence was good, and he had decades of it. But good point and thank you for reading.
Nice article, germ theory is wrong though.
This view of position on the airborne transmission is simply false, and uses a bunch of nice story telling to pass the pill while not citing any evidence.
The reality is that there is a spectrum of transmission between large ballistic droplets and suspended aerosols that is pretty much a consensus within virologist community. For an example, here is one from Ian Mckay: https://virologydownunder.com/flight-of-the-aerosol/ from 9th of February 2020 and a prior version from at least 2016 (for flu transmission); here is a version from May 2020 document published by the AUS government specifically indicating the extent and our confidence for the required droplet size: https://cpb-ap-se2.wpmucdn.com/blogs.auckland.ac.nz/dist/f/688/files/2020/05/Is-SARS-CoV-2-airborne-14-05-2020.pdf.
Moreover, SARS-CoV from 2004 was declared to be transmissible through aerosols, just as well as measles - meaning that a suspension could remain in the air for hours and hours infecting anyone passing through the cloud.
For SARS-CoV-2 specifically, there were early on attempts to see if it could be transmitted by aerosols by experiments where the virus was aerosolized and then the suspension aspirated and checked for the vRNA presence (positive) and possibility to give cultures after aspiration (negative).
There was never a question of aerosolization not being a consensus in the medical community: it was more of a question of usage of language and the scientific publications about it were very clear from the start: https://www.nature.com/articles/d41586-020-00974-w
Hey Andrei thanks for reading and taking the time to comment. I'm not sure what your issue is though. My primary concern is that - in the US in particular - we are not *behaving* as if Covid is an airborne virus.
1. We emphasize ventilation and air filtration very little.
2. We don't have a general mask standard for media and fit, and we do not emphasize fit.
3. We treat plexiglass and six feet of distance as if they somehow prevent transmission.
4. We - companies, schools, etc - advertise how we are sanitizing surfaces, but few invest in other measures that would make a bigger difference.
I am not a virologist, but form what I understand, culturing virus from the air is very difficult. But recent research does suggest that a lot of virus is in smaller aerosols (<5µm) that do float through the air. https://academic.oup.com/cid/advance-article/doi/10.1093/cid/ciab691/6343417
I don't have any issue with the idea that there's a spectrum of transmission and do agree that much of the problem is about cross-discipline terminology, but lack of public understanding about airborne risk suggests that there is a problem to me. Again, thanks for taking the time to read and provide feedback.
Nice article, but the essence of the story is that science is managed by idiots that dont think for themselfs. Testosterone fuelled balled old men. Anyone who challenges their views is punished untill the evidence becomes overwhelming enough that it cant be denied anymore. Then they will find ways to get the credit for it and say that they knew that all along
This is very nicely written and a great history of epidemiology. However, I'm not convinced by the core thesis.
The idea that viruses can travel long distances in the air is not actually controversial within the field. There are papers exploring "aerobiology" and which investigate the possibility that influenza is spread around the world by the wind. They are obscure but they exist and they were published in recent decades. More surprisingly, Ferguson et al first came to the world's attention during the UK outbreak of foot and mouth disease. The story was the same: their models predicted huge disaster if there wasn't totalitarian state action, in that case, mass killings of farm animals whether they were infected or not. Their recommendation was to destroy entire farms simply because they were downwind of farms that had infections, even if no foot-and-mouth was detected on the farm itself. The models were later invalidated by accidental control cases, but not before funeral pyres of animals filled the skies with smoke.
So I think you are giving public health too much credit as a profession. In your telling they are basically well intentioned but hopelessly conservative to the extent that they ignore evidence they're wrong until they literally die of old age. This conservatism explains their reluctance to consider long range airborne transmission.
The evidence I see when reading modern epidemiology papers is different. If airborne transmission lets them recommend extreme, dramatic state action, they model airborne transmission. If it would undermine the case for totalitarian state action, as it would for lockdowns, then airborne transmission doesn't exist. None of this is tied to microbiological theory: despite what you'd expect, epidemiology is a microbiology free zone.
There's really only one thing that seems to coherently explain public health decisions: they pick whatever "explanation" gives them the most power and doesn't require them to admit mistakes. There's nothing more to it than that. Public health is really one of the most corrupt and dangerous fields I've ever encountered. Their papers are filled with errors and they don't care because they realised they can just stare down politicians and most of the public, regardless of how inconsistent their supposed expertise is with collected data. Mark my words: if someone figures out a way to control people's lives even more through a long range transmissible, airborne virus tomorrow, then the day after tomorrow such a virus will have emerged and be being used as a policy justification. Perspex plates will be immediately forgotten and anyone who remembers them too loudly will be banned for misinformation.