This is fascinating: Researchers looked at variations in the human leukocyte antigen (HLA) genes of people who had confirmed cases of Covid before the vaccine rollout and also had genetic records on file.

Those with a particular variation were twice as likely to have been asymptomatic.

Having that same variation from both parents made them 8.5 times as likely to have been asymptomatic!

They looked at two more cohorts and found the same results.

And then they looked at T-cells collected before the pandemic, and found that the ones with this allele responded more actively to SARS-COV2, despite never having been exposed to it before. That lends weight to the hypothesis that some people’s immune systems were able to recognize it as similar to more run-of-the-mill coronaviruses.

Next they want to broaden the study more to include people with a wider range of ancestry.

It doesn’t come close to explaining all asymptomatic cases, and they didn’t look at how it might stack with immune responses that are actually targeted at covid (vaccines, prior infections), or whether it also reduces the chances of long-term damage from covid.

But wouldn’t it be great if someone could come up with a supplement based on what this HLA variant produces that’ll cause your immune system to generalize better? Even if it’s just within coronaviruses?

For the second day in a row we’ve gotten a notice of a Covid exposure in the kid’s classroom. One more case and it’s technically an outbreak.

Mask-optional was one thing when cases were low and flat, but the numbers have been climbing for weeks. And that’s not including however many at-home tests don’t get reported. The classroom is now mask-required for the next 10 days, which means the rest of the school year.

Fortunately the kid’s been wearing N95s since before the first exposure!

I looked up the county regs for what to do after a third case. They’re wonderfully vague: “If a DPH outbreak investigation is activated, a public health investigator will contact the school to coordinate the outbreak investigation.”

Well, it’s going to put a damper on end-of year parties, even if it stops here.

Update June 10: They managed to get through the rest of the school year without another Covid case!