Wednesday, June 17, 2020

Lockdowns Don't Work. But Masks Do.

NOTE:  As of August 14, 2020, the TSAP's positions taken in this article are hereby superseded by those in a newer post.  Also, since the article was posted, the study that formed the primary basis for this article has apparently been recommended by over 40 scientists to be withdrawn due to its apparent flaws.

That is essentially the conclusion of a new study that looks at the (former) COVID-19 hotspots of Wuhan, NYC, and northern Italy.  Based on the relative timing of when social distancing measures, stay-home orders (i.e. lockdowns), and mandatory mask rules were first imposed, the researchers found a strong inverse correlation with COVID-19 cases and mask requirements, while barely any correlation with social distancing and stay-home orders.

(And not the only study either.  Though other studies do find some degree of effectiveness for social distancing as well.)

Unfortunately, the study authors kinda shoot themselves in the foot by effectively conflating as "airborne" both larger ballistic droplet as well as small aerosol droplet transmission.  The strong inverse correlation with mask wearing would if anything make even more sense for catching larger droplets than smaller ones.

Either way, while correlation does not prove causation, this is nonetheless a pretty strong correlation.  Thus, there is no good reason not to reopen the economy at this point, and quite frankly, yesterday is not soon enough.  During the reopening process, state governors (Ducey of Arizona, I'm looking at you!) really ought to require masks to be worn in public, particularly indoors (which is far riskier than outdoors) and during the most critical and riskier phases of the reopening process.

And of course, We the People really need to wear them, yesterday.  At least in indoor public spaces and public transit, or any other crowded area where sufficient physical distance is difficult or impossible.  Even if it is just for the next few weeks or so, it will still make a big difference, especially in reducing the overshoot beyond the herd immunity threshold in places that are at or approaching that threshold.  In fact, as source control, when a large enough percentage of the population wears masks, it can effectively simulate herd immunity, and the virus will thus quickly run out of momentum and die out.  And all without wrecking the economy and society at large, and with minimal effect on individual rights.

That said, the TSAP should clarify that we support mask mandates that are nuanced and temporary, not absolute or permanent.  Absolute (i.e. without nuance) ones should not last more than two weeks in any case, and the much lower risk of outdoor transmission should be taken into account by mandates lasting longer than that.

It is worth noting that the states with mandatory mask requirements have seen decreases in COVID-19 cases, while the states without (including California, who only very recently implemented such a requirement, thus the effects haven't kicked in yet), have seen significant increases.  And that is true even though all 50 states and DC have reopened to one degree or another at some point.  It is hard to find a correlation stronger than that.

So even if there is a surge in cases, resist the impulse to lock down again.  Simply require masks to be worn in public, particularly indoors, and tighten limits on building occupancy and large gatherings.  That's it.  Add some temperature checks and you're golden.  Maintain such policies until case numbers drop to a statistically and practicallly negligible level, then repeat as necessary.  As for a vaccine or cure, don't hold your breath, since a vaccine is likely years away, while anything resembling a (belated) cure would most likely not be much of a game-changer compared to existing treatments (remdesivir, steroids, etc.).

As for contact tracing, they really need to step it up.  And any supposed shortage of testing capacity (even after having many months to prepare!) is no excuse not to do it, as Japan was able to do retrospective contact tracing successfully with very little testing (2000 tests per day, equivalent to about 5000 per day in the USA), focusing on the larger clusters and thus the "superspreaders" that account for the vast, vast majority of virus transmission in the community.

And perhaps COVID-sniffing dogs will soon become a thing as well.  Apparently they exist.  Regardless, all of these aforementioned alternatives are far better than a return to lockdown.  So what are we waiting for?

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