A YouTube video about COVID-19: what does it say? Anything surprising or new? I don’t know.

A reader recently sent me a link to this YouTube video, which is about 37-1/2 minutes long. I have watched the first nine minutes with dwindling expectations. The first controversial statement that threw me happened during the first minute and twenty seconds when the narrator stated (roughly) that about 80% of the population is essentially immune to the novel coronavirus because of prior infection with other common coronaviruses. This was a big surprise to me and made it difficult to watch the rest because there were a lot of things I had to look up.

(So a “Gompertz” curve is just a sigmoid curve… had to look that one up. It seems that  Benjamin Gompertz (1779–1865) was an English mathematician and actuary who developed his curve or function to fit death rates in the general population. His function has been fitted to COVID-19 infection rates– see this paper in PLOS One. The Gompertz function predicts a succession of rates: slow rise, rapid rise, slow rise, asymptote. Oops, total infections still rising. Curve fitting didn’t predict current daily infection rates or “second surge.” Back to drawing board.)

As you may already know, there are several common coronaviruses in constant circulation among human populations. Each of these causes syndromes that we call the “common cold”– so far, there are four known coronaviruses that account for up to 30% of colds and roughly 90% of people have antibodies to at least three of the four. The similarity of these coronaviruses to SARS-COV-2 is supposed to give most of us at least partial immunity to COVID-19 which may prevent overwhelming infection. This is an hypothesis, not a proven fact.

It is true that there is cross-reactivity between the common cold viruses and SARS-COV-2, that is, human immune cells from people who have never had COVID-19 will often recognize parts of the novel coronavirus– see, for example, this article in NIH Research Matters from August 18. This observation is advanced as an hypothesis for why some people get milder illness when they catch COVID-19. It does not, however, “prove” that 80% of the population is immune to SARS-COV-2. This has not been established at all.

Inquiry into this topic, i.e. a Google search of the term “immunity to SARS-COV-2 due to prior infection with common coronaviruses” leads to this fascinating review paper, “Lessons for COVID-19 Immunity from Other Coronavirus Infections” in Cell dated August 18, 2020. It discusses various aspects of numerous other types of coronavirus infections found in animals. These include the cat disease lethal feline infectious peritonitis, which can be treated with remdesivir (available from China, very expensive– see my previous post on this topic.)

But I digress. Now there is another long research paper to read, this time a review of (mostly) animal coronaviruses, on top of a long YouTube video which has not started off well. I have no life, so no matter.

PS: The sky is not orange, the way it is in San Francisco, but we have had significant ash fall here and the sun looks orange in the morning; also, it is much cooler than predicted, probably because the sky is so smoky. Our thoughts are with those who are suffering from the fires. It seems that the coronavirus pandemic is only one of the signs of the Apocalypse, which is apparently right around the corner.