2021-08-14 General

Mitigation Measures

Huh. This web page from the US CDC says that an N95 with an exhalation valve is as good or better at source control (i.e. protecting the people the wearer is close to) than a procedure mask (the standard medical hook-over-your-ears mask that you see unfortunately frequently see lying on the ground as trash). Presumably a vented N95 is not as good as at source control as an N95, but it ought to be good enough for going to the grocery store.

Vaccines

This paper says that getting a MMR (measles/mumps/rubella) or Tdap (tetanus/diptheria/pertussis) vaccine gives some protection against COVID-19. Note that MMR (which gives ~35% protection) uses live attenuated viruses (which I discussed on 18 May 2021 and 12 June 2021). Tdap (which gives ~25% protection) does not use live attenuated viruses, as far as I can tell.


In this tweet thread, the author argues against various recent studies which suggest that vaccine effectiveness is waning. This tweet thread discusses why vaccine effectiveness might look like it is going down even when it is not. Imagine a vaccine that gives everybody a 95% chance of avoiding infection when exposed: given enough time (and so enough exposures), one will break through for any given person. Given enough time, all people (except hermits) will get exposed, so the calculated vaccine effectiveness will drop to 0%.


PM Trudeau announced that they’ve signed a deal to buy 40M doses of Moderna over the next two years, with the option to go to 65M doses. My response is “WHY????” That’s enough to vax half the population. Yes, we need vax for the kids, but that’s probably less than 4M people (8M doses). Maybe this is for boosters to counteract variants? Maybe it’s the cost Moderna extorted for Canada to get to have a Moderna plant (also referenced in the article).

Variants

This preprint found that there is one gene (the P681R mutation) responsible for Delta’s enhanced transmissibility. They took Delta, switched out P681R with the Alpha version or the original (Wuhan) version of that gene, and compared their effects (in test tubes, don’t worry) and found that the stock Delta versions way outcompeted the Delta+Alpha mutation and Delta+Wuhan mutation versions. I’m not sure how we will use this information, but it seems like an important thing that will be useful later.

MIS-C

Okay, bear with me, I am learning about this area so don’t understand it well enough to be concise.

MIS-C, Multi-Inflammatory Syndrome in Children, is a really nasty side effect of COVID-19 that kids sometimes get, and it looks kind of like Toxic Shock Syndrome.

“Antigen” is something which an antibody attacks by binding to. Think of it sort of as an irritant.

There are some molecules called “superantigens“. These are really bad: they rev the immune system up way past what is healthy. Toxic Shock Syndrome is caused by superantigens.

This paper (from October 2020) says that SARS-CoV-2 has structural similarities to known superantigens.

Meanwhile, endogenous retroviruses (ENVs) are kind of ghosts of ancient retroviruses that haunt our DNA. They live in our DNA and can’t reproduce. There is some evidence that they are somehow involved in Multiple Sclerosis, ALS, diabetes, lupus, and/or addiction.

This new preprint says that they found elevated levels of antibodies to ENVs in children with lupus & MIS-C. In a tweet thread about this preprint, there is speculation that MIS-C is caused by superantigens derived from endogenous retroviruses.

Recommended Reading

This article talks about the next pandemic: what we need to do to stop it versus what we are doing.

Editorial: Do you, Dear Readers, want more detail in the Recommended Reading section? Do y’all actually ever read the article? Are they in fact as good as I think they are?