Ben Thompson, Stratechery:
This is where masks come in. Much of the discussion of their
efficacy has been focused on whether they keep you safe from
the virus, and the evidence suggests that the answer is
probably. SlateStarCodex has a comprehensive overview of the
Everyone agrees, though, that those who are sick should wear
masks; as the Taiwan CDC puts it, “Masks are mainly used
for preventing the spread of disease and protecting people around
you.” This, though, highlights the shortcomings of the “Don’t wear
masks if you’re not sick” recommendations:
First, people are terrible in general at estimating if they are
sick, particularly if their symptoms are mild.
Second, as Zeynep Tufekci argued in the New York Times,
saying that only sick people should wear them stigmatizes the
sick and makes them less likely to wear them.
Third, and most importantly, asymptomatic transmission means you
don’t even know if you are sick in the first place.
Best estimates at this point suggest that up to 1 in 4 people infected with COVID-19 are asymptomatic — a staggering number.
Trust me, I was fully on board with the WHO/CDC recommendation not to wear a mask unless you’re feeling sick. I’m sure most of you reading this in the U.S. are still on board with that. It’s time to admit the WHO and CDC led us grossly astray on this.
Given what we now know about transmission — that it primarily spreads through large droplets — even homemade masks are more effective than no mask at all. I firmly believe we should all wear masks to help keep ourselves from contracting the virus. But even if after reading all of this you still think masks should only be worn by those who are sick, the fact that up to 25 percent of those infected are asymptomatic (but still contagious) means that without widespread testing we should all wear masks.
★ Wednesday, 1 April 2020