A Few Notes on Masks
One possible explanation for the slowdown in COVID-19 outbreaks is that masks are unusually effective with this disease. When the pandemic started, masks were discouraged and the doubling time was measure in days. Now the doubling time is measured in weeks.
We see an interesting phenomenon: When the COVID-19 death rate gets higher than 3 per million per day, it tends to come down. The most plausible explanation is higher death rates cause people to wear masks.
There appears to be an anti-mask campaign going on. It's giving me a strange, new respect for the anti-lockdown conspiracy theories of a month or two earlier. After all, if this were a plandemic to ruin the US economy, the people behind that would not want public-health measures that are harmless to the economy.
One of the claims of the anti-mask movement (that they interfere with oxygen) can be easily disproved. I put a mask on and measured my blood O2 with a pulse oximeter. It read 95%. I took the mask off and it still read 95%. I repeated the test a month or two later. My blood O2 with the mask on was 96%. With the mask off the oximeter flickered between 96% and 97%. For some reason, not many of the people retweeting the anti-mask claim tried that. You can try it yourself. You can easily order an oximeter. Don't just take my word for it. Nullius in verba!