2022-02-05/06/07 General

Long COVID

This paper and this preprint says that people who have recovered from a COVID-19 infection are at greater risk from heart complications afterwards. The first study followed patients for the next year and found that patients had the following elevated risk of any heart issue in the following year compared to non-infected controls:

  • non-hospitalized patients: 1.39x;
  • hospitalized but non-ICU patients: 3.43x;
  • ICU patients: 6.19x.

The second paper looked at patients after 90 days, and found a elevated risks:

  • 14.76x for myocarditis and pericarditis;
  • 7.38x for thrombocytopenia;
  • 6.37x for pulmonary embolism;
  • 3.89x for acute myocardial infarction;
  • 2.31x for cerebral infarction and non-ischemic stroke.

COVID-19 is not like the flu.

This paper and this paper did surveys of children and adolescents about Long COVID. Both studies found that the kids who had tested positive had more symptoms than the controls, but I was surprised at how small the differences were. For example, 66.5% of the positive kids reported at least one symptom, but 53.3% of the controls also did. 53% sounds like a lot to me.

<rant> I really wonder how useful surveys are which ask overly broad, subjective/non-measurable, and which don’t ask good about severity are. “Did you have a headache ever in the last year?” OF COURSE THEY DID. Almost everyone did!</rant>

Vaccines

This preprint from a Seattle biotech company making an mRNA vaccine says that one of their vaccines, tailored to Omicron, did better against Omicron in mice than the ones targeted to COVID Classic. However, their Omicron vax didn’t work well as a booster if the mice had gotten a shot of a COVID Classic-targeted vax earlier. (This is not totally unexpected. It’s a known effect called original antigenic sin. Essentially the team gets cocky and says, “aw, we’ve seen this before, we know how to deal with this, shove off” when the coach (vaccine) tries to get them to train.)

This study looked at four (academic) mRNA vaccines with:

  1. the Delta spike;
  2. the Omicron spike;
  3. a hybrid spike which had all of the point mutations from both Delta and Omicron;
  4. a mixture of a half-dose of the Delta spike vaccine (#1 above) and half of the Omicron spike vaccine (#2 above).

They found that #2 and #3 gave very high antibody levels against Omicron, but they were crap against all the other variants. #2 was especially crappy against other VOCs, just an absolute dog. However, #1 and #4 worked well against COVID Classic, Beta, Delta, and Omicron.

Pathology

This preprint from Seattle says that the rate of pediatric croup about doubled when Omicron showed up.

Variants

This preprint says that Omicron is intrinsically less likely to cause hospitalization or death than Delta in adults, while Omicron and Delta have about the same risk for children. (Yes, they factored in vaccination status and prior infection with COVID-19.) Vaccination and prior infection both reduced the risk of hospitalization or death.

This article on how the pandemic has changed the workplace is thoughtful.