2021-05-18 General


 I took a look at a paper about a South African trial of AstraZeneca — I think this is the final paper of the preprint I’d seen before — and it says that AZ is really crappy against B.1.351. I knew that, I preach that.

HOWEVER, something I hadn’t noticed before is that there were no severe cases in either the vax or placebo branches of the trial. That means we don’t just don’t know how much protection against severe disease the AZ vax gives.  Might be a lot, might not be.

Meanwhile, there is another paper about B.1.351 in hamsters (which are a good animal model).  It showed poorer antibody response against B.1.351 than to COVID Classic, but still the hamsters didn’t get very sick.

So maybe AZ isn’t quite as bad against B.1.351 as I thought. As someone who has gotten one dose of AZ so far, that makes me happy.

Something which makes me even happier is that a mix&match study in Spain says that AZ first dose/Pfizer second dose gives seven times more neutralizing (i.e. useful) antibodies than AZ for both doses! This does not mean that it’s seven times as effective (uh, that would be difficult), but it does mean that it is likely that AZ+Pfizer is more effective than AZ+AZ. I expected this, but it’s nice to get a piece of supporting evidence. 🙂

There is a really interesting article calling for more research at using live attenuated virus vaccines (LAV), for fast, cheap, poor-effectiveness-but-better-than-nothing responses to pandemics. It says that LAVs don’t just stimulate the B and T cells’ immunity, they also stimulate the innate immune system for a while against lots of pathogens. (For example, oral polio vaccination campaigns in West Africa have been associated with a 25% reduction in all-cause mortality.)

Random LAVs’ protection isn’t as good as vaccines targeted to a specific disease, and the protection isn’t as long-lasting, but it does give some protection.

How do LAVs do this? We don’t know, this effect has not been studied much, hence the call for more research. But maybe next time a pandemic comes through, you should go get a measles booster.

Mitigation Measures

Something I missed while I was out: talks have started about reopening the Canada-US border. There’s no telling how long the discussions will take, but it’s interesting that they have at least started.


This article doesn’t think that the summer weather is going to (by itself) help the pandemic. NB: someone pointed out that article was from April 2020! Oops.


Canadians can travel to the US without a quarantine to get vaccinated with a doctor’s note but they have to come IMMEDIATELY and DIRECTLY home (no stopping to buy milk!) and wear a mask in all public spaces for 14 days.