‘The Case for Universal Cloth Mask Adoption & Policies to Increase the Supply of Medical Masks for Health Workers’

White paper jointly authored by seven professors at Yale, including economists, statisticians, and MDs:

We estimate that the benefits of each additional cloth mask worn by the public are conservatively in the $3,000-$6,000 range due to their impact in slowing the spread of the virus. The benefits of each medical mask for healthcare personnel may be hundreds of times larger, and there is an ethical imperative to safeguard frontline healthcare workers. We must both encourage universal mask adoption and deal with the urgent policy priority that front-line healthcare workers face shortages of personal protective equipment, such as N95 respirators and surgical masks.

Twitter thread from lead author Jason Abaluck:

We have very good evidence that universal adoption of cloth masks will combat the spread of the virus. Specifically, we know that 1) asymptomatic people spread the virus, 2) mask wearing by infected people prevents them from transmitting the virus (the report provides citations).

How large are the benefits? Even if masks reduce transmission probabilities by only 10% (and as you’ll see, that is likely very conservative), the value of each cloth mask is between $3,000 and $6,000. Our best estimate is that their protective value is closer to 40-50%.

These estimates are of course sensitive to the assumptions made in the underlying epidemiological models. But even if those models overstate mortality risk by a factor of TEN, each cloth mask conservatively generates $300 in value!

Basically: even if cloth masks only reduce the rate of transmission a little (say 10%), every single one worn is incredibly valuable. And the current best estimates are that cloth masks in fact reduce transmission by 40-50%.

Both the paper and Abaluck’s tweet thread are worth reading in full. But the takeaways are: make cloth masks and wear them if and when you must venture out; reserve all medical-grade masks for health workers.

And I’ll add this: it’s humiliating that the richest nation in the history of civilization has no supply of paper fucking surgical masks. We should be handing them out like candy but we can’t.

★ Friday, 3 April 2020