Obviously human trials of diseases are difficult to do in general, but studying transmission of colds is particularly difficult because “the common cold” isn’t one virus genus, or even one virus family. Wikipedia notes:
Well over 200 virus strains are implicated in causing the common cold, with rhinoviruses, coronaviruses, adenoviruses and enteroviruses being the most common.
Certainly, many types of virus responsible are basically only transmitted via surfaces, but obviously COVID can be transmitted by aerosols. There are almost certainly some kinds of “common cold” that can be transmitted by aerosols, too. But it’s not feasible to do human studies of so many virus types—consider how hard it was for society just to realize that COVID was transmitted via aerosols!
It seems like a catastrophic civilizational failure that we don’t have confident common knowledge of how colds spread.
Given the context above (posted by bhauth), the problem seems intrinsically hard. What would make this a civilizational failure? To my eye, that label would be warranted if either:
in alternative timelines with the same physics and biological complexity, other civilizations sometimes
figured out transmission. If the success rate is under some threshold (maybe 1%), it suggests variation in civilization isn’t enough to handle the intrinsic complexity. (This option could be summarized as “grading on a multiverse curve”.)
deaths from the common cold (cc) met the criteria of “catastrophic”. The cc costs lives, happiness, and productivity, yes, but relative to other diseases, the “catastrophic” label seems off-target. (This option
is analogous to comparing against other risks.)
Yep, that is a big question mark that I note in the conclusion:
Might depend on details of specific viruses, and I don’t think we’ve done enough research to have meaningful evidence about whether different RVs have very different transmission profiles from each other.
(And also implicitly in a few places within the body of the post.)
I think it’d be reasonable to apply a large discount to any updates you’d otherwise make on the question of rhinovirus transmission from this post, at least absent a follow-up investigation re: whether they behave similarly or not.
consider how hard it was for society just to realize that COVID was transmitted via aerosols!
It was only hard because inexplicably no one bothered checking for over a year into the pandemic, we just took the whole “fomites and large droplets” stuff from cold and flu for granted despite the evidence being as we see here pretty scant. There’s a serious coordination problem there IMO in how chaotic research ended up being rather than exploring systematically and rapidly all these very obvious things that we should have had some decent evidence on by April/May 2020.
March 17, 2020: Doremalen et al, NEJM (experimental) showed SARS-CoV-2 remains viable in aerosols for hours, supporting airborne spread.
March 19, 2020: Zou et al, NEJM (virology observational) showed that SARS-CoV-2 reaches extremely high viral loads in the nose and throat at or before symptom onset which explained the ease of presymptomatic transmission and why COVID-19 spreads so efficiently through shared air.
March 26, 2020: Bourouiba et al, JAMA (mechanistic) highlighted that SARS-CoV-2 can spread much farther than current social distancing guidelines suggest (far past the social distance recommendation of 6 ft, up to ~23-27 ft), especially indoors
April 2, 2020: Lu et al., Emerging Infectious Diseases (outbreak investigation) found COVID-19 spread between diners seated ~1 m apart only along AC airflow, inconsistent with simple droplet spread alone. Evidence that airflow-borne respiratory particles drive indoor transmission
April 10, 2020: Lidia Morawska and Junji Cao Environment International (commentary) warned that COVID-19 spreads through the air, arguing that aerosols can travel meters indoors and urging ventilation and masking.
May 14, 2020: Sia et al., Nature (animal model / hamster study) showed SARS-CoV-2 spreads efficiently between hamsters through the air, becoming key evidence that inhaling a relatively small airborne dose over a short time can be enough to establish infection
May 15, 2020: Hamner et al., MMWR (CDC outbreak investigation) reported the Skagit Valley choir superspreading event, where one symptomatic singer infected ~87% of attendees in ~2.5 hours. The authors note singing increases aerosol emission, making droplet-only spread unlikely
May 27, 2020: Morawska et al. / Group 36, Environment International (expert correspondence): A group of 36 international aerosol, indoor-air, HVAC, and infectious-disease experts warned that airborne transmission of SARS-CoV-2 indoors was being downplayed, and called for ventilation, filtration, reduced air recirculation, and other clean-air engineering controls to limit spread
June 11, 2020: Zhang et al., PNAS (epidemiological analysis): Analyzed outbreak trends in Wuhan, Italy, and NYC and argued that airborne transmission was the dominant driver of COVID-19 spread and wearing masks as the most effective way of preventing spread
....and so on.
We knew. It was also suggested by the WHO in the infamous ‘military word: airborne’ press conference, 11 Feb 2020, and was explicitly acknowledged as a possibility in the WHO briefing on July 7 2020.
Obviously human trials of diseases are difficult to do in general, but studying transmission of colds is particularly difficult because “the common cold” isn’t one virus genus, or even one virus family. Wikipedia notes:
Certainly, many types of virus responsible are basically only transmitted via surfaces, but obviously COVID can be transmitted by aerosols. There are almost certainly some kinds of “common cold” that can be transmitted by aerosols, too. But it’s not feasible to do human studies of so many virus types—consider how hard it was for society just to realize that COVID was transmitted via aerosols!
Given the context above (posted by bhauth), the problem seems intrinsically hard. What would make this a civilizational failure? To my eye, that label would be warranted if either:
in alternative timelines with the same physics and biological complexity, other civilizations sometimes figured out transmission. If the success rate is under some threshold (maybe 1%), it suggests variation in civilization isn’t enough to handle the intrinsic complexity. (This option could be summarized as “grading on a multiverse curve”.)
deaths from the common cold (cc) met the criteria of “catastrophic”. The cc costs lives, happiness, and productivity, yes, but relative to other diseases, the “catastrophic” label seems off-target. (This option is analogous to comparing against other risks.)
Yep, that is a big question mark that I note in the conclusion:
(And also implicitly in a few places within the body of the post.)
I think it’d be reasonable to apply a large discount to any updates you’d otherwise make on the question of rhinovirus transmission from this post, at least absent a follow-up investigation re: whether they behave similarly or not.
It was only hard because inexplicably no one bothered checking for over a year into the pandemic, we just took the whole “fomites and large droplets” stuff from cold and flu for granted despite the evidence being as we see here pretty scant. There’s a serious coordination problem there IMO in how chaotic research ended up being rather than exploring systematically and rapidly all these very obvious things that we should have had some decent evidence on by April/May 2020.
March 17, 2020: Doremalen et al, NEJM (experimental) showed SARS-CoV-2 remains viable in aerosols for hours, supporting airborne spread.
March 19, 2020: Zou et al, NEJM (virology observational) showed that SARS-CoV-2 reaches extremely high viral loads in the nose and throat at or before symptom onset which explained the ease of presymptomatic transmission and why COVID-19 spreads so efficiently through shared air.
March 26, 2020: Bourouiba et al, JAMA (mechanistic) highlighted that SARS-CoV-2 can spread much farther than current social distancing guidelines suggest (far past the social distance recommendation of 6 ft, up to ~23-27 ft), especially indoors
April 2, 2020: Lu et al., Emerging Infectious Diseases (outbreak investigation) found COVID-19 spread between diners seated ~1 m apart only along AC airflow, inconsistent with simple droplet spread alone. Evidence that airflow-borne respiratory particles drive indoor transmission
April 10, 2020: Lidia Morawska and Junji Cao Environment International (commentary) warned that COVID-19 spreads through the air, arguing that aerosols can travel meters indoors and urging ventilation and masking.
May 14, 2020: Sia et al., Nature (animal model / hamster study) showed SARS-CoV-2 spreads efficiently between hamsters through the air, becoming key evidence that inhaling a relatively small airborne dose over a short time can be enough to establish infection
May 15, 2020: Hamner et al., MMWR (CDC outbreak investigation) reported the Skagit Valley choir superspreading event, where one symptomatic singer infected ~87% of attendees in ~2.5 hours. The authors note singing increases aerosol emission, making droplet-only spread unlikely
May 27, 2020: Morawska et al. / Group 36, Environment International (expert correspondence): A group of 36 international aerosol, indoor-air, HVAC, and infectious-disease experts warned that airborne transmission of SARS-CoV-2 indoors was being downplayed, and called for ventilation, filtration, reduced air recirculation, and other clean-air engineering controls to limit spread
June 11, 2020: Zhang et al., PNAS (epidemiological analysis): Analyzed outbreak trends in Wuhan, Italy, and NYC and argued that airborne transmission was the dominant driver of COVID-19 spread and wearing masks as the most effective way of preventing spread
....and so on.
We knew. It was also suggested by the WHO in the infamous ‘military word: airborne’ press conference, 11 Feb 2020, and was explicitly acknowledged as a possibility in the WHO briefing on July 7 2020.