2021-09-22 General

Vaccines

In this study, the authors made pseudoviruses — things which have SARS-CoV-2 spikes on them but which can’t infect people, and “mutated” the spikes. They were able to find a mutant spike that were almost completely resistant to antibodies from either people who had had COVID-19 and had not been vaccinated or who had gotten vaccinated but had not been infected. However, antibodies from people who had been infected and vaccinated were able to get rid of pseudoviruses with the mutant spike.

Note: there have been a number of papers recently which have said that infection plus vaccination gives more robust response than either infection or vaccination, but they weren’t straightforward to explain. This paper had the clearest, most explainable results, but I want to emphasize that it is consistent with other stuff I have been reading.

This does NOT mean you should run out and get infected! It does suggest to me that mixing and matching vaccines is a good idea. (We are still waiting for the big UK mix&match study to finish up; it’s supposed to be done soon.)


This press release says that giving a second J&J shot six months after the first J&J shot, after one week, antibody levels were 9x higher than after the first shot. Four weeks after the booster, antibody levels were 12x higher than after the first shot.


I read the full measles paper today (instead of just the abstract), and something which I missed (so was not in yesterday’s post) is that the MMR vaccine does NOT give any protection (well, maybe 8% effectiveness) against asymptomatic infection. It does give 48% effectiveness against symptomatic infection.

The full paper speculated that the MMR vaccine stimulates the innate immune system (which I’ve read also, this is not new or controversial), but it also points out that the MMR viruses are also mRNA viruses, and so might give an extra boost against mRNA viruses like coronaviruses. There are also a few places where the coronavirus has the same proteins as places in either the measles virus or the rubella virus, so some of the antibodies to one could possibly help clear the other.


This study comparing Comirnaty and Spikevax in health care workers in the US found that they were both good, but Spikevax edged Comirnaty slightly:

Vaxafter dose1after dose2
Comirnaty77.6%88.8%
Spikevax88.9%96.3%

They did see some waning of effectiveness over 13 weeks, though it was slight:


This preprint says that while kidney dialysis patients’ responses are crappy to both Comirnaty and Spikevax, Comirnaty is less crappy.


This slide deck, of results of a huge (20M people, with 5.6M fully-vaccinated!) Medicare study in the US, says that:

  • Vaccine effectiveness does seem to wane over time.
  • Vaccine effectiveness against Delta is not as good as against COVID Classic.
  • The drop in effectiveness was worse for the elderly.
  • There was a 2.6% breakthrough rate for people over 65.
  • Of the breakthrough cases, 20% needed hospitalization, which is a third lower than the case hospitalization rate (32%) between March and December 2020 (i.e. pre-vaccinations).
  • Of the breakthrough cases, 2.2% died, which is 1/6th of the pre-vaccination case fatality rate (12%).
  • They calculate a 41% vaccine effectiveness against infection and 62% VE against hospitalization.
  • Risks are not distributed uniformly:

This press release says that SBC-2019, the Clover Biopharmaceuticals vaccine manufactured in China, has finished a large (30,000 people) Phase 2/3 trials with good results:

  • The vaccine was 100% effective against hospitalization overall.
  • The vaccine was 84% effective against moderate-to-severe infection overall.
  • The vaccine was 67.2% effective against infection of any severity overall.
  • The vaccine was 78.7% effective against Delta infection of any severity, 91.8% against Gamma, and 58.6% against Mu.

SCB-2019 is a protein subunit vaccine, meaning that it just has little pieces of parts of the virus, making it really stable compared to mRNA vaccines, and using a very mature manufacturing technology.


This article says that Canada has paused further shipments of vaccine because it now has more than it needs. This is not a surprise, but it is a formal recognition/announcement.


Members of the camelid family and some fish have analogues to our antibodies (called “nanobodies”) which do the same thing as antiboies but are chemically structurally slightly simpler. The authors of this preprint vaccinated a llama, then looked for useful nanobodies, and found four highly promising ones. Those might be useful therapies.

Transmission

This article is about some poll workers who say that Elections Canada put them at risk in the election on Monday. They said that people weren’t required to wear masks or to distance.

I actually was a Deputy Returning Officer (DRO) (the person who hands out ballots and later counts them) on Monday, so I guess I’ll add what I saw:

  • Every single voter had a mask on. One or two had them slipping down slightly, but I don’t think I saw any nostrils. I only saw three people without masks — all poll workers — during the whole day, not counting a few people lifting their mask briefly to take drinks of water or (late in the evening) to eat some quick bites of snack food.
    • One worker forgot her mask, and it took about five minutes to get her a mask when we started working.
    • One supervisor took off his mask when he phoned in the results because the person on the other end was having a hard time understanding him. (We were in the basement of the library and I think the signal wasn’t good.) I can understand that, but then he apparently forgot to put his mask back on afterwards.
    • I went out to the bathroom and discovered a candidate’s representative without a mask in an area which was open to the atrium, so while it was not technically outside, they were in a very large space, and nobody else was anywhere near them. Plus, when they saw me, they immediately put their mask on.
  • The poll workers did not do a particularly good job of always maintaining 2m distance. There were at least two times where I approached a more experienced person to ask a question, keeping two metres away, and they walked closer to me to get to a more comfortable speaking distance, at which point I moved backwards to maintain the distance. The people I was talking to then stopped, perhaps realizing what was going on.
  • There were a few times when I called over a supervisor to ask a question about a situation, and the supervisor frequently was closer than 2m. I would scoot my chair away when I could, but that wasn’t always possible. These interactions were brief.
  • MOST of the time I was quite far from people.
    • I sat about 4m from the nearest other DRO. In other years, there would be two people at a desk, but because COVID, there was just the one DRO.
    • There was a plexiglass barrier between me and the voters, with a cutout at the bottom where they could slip their ID.
      • One voter had a hard time hearing me and knelt so that her ear/face was at the level of the cutout.
      • Occasionally (five times?) voters would move to the side of the barrier briefly — sometimes to hear me better, sometimes because they were moving in that direction to reach the voting-privacy-screen. This was always brief.
      • I rarely spoke to a voter for more than five minutes. Usually it was more like 90 seconds. If I had to fill out a registration form or a correction form, it might be five minutes, but there were probably only about 15 of those that I had to do.
  • The room was quite large for the number of people we had in there, and there were two double doors open for almost the whole day.
  • For most of the day, the Information Officers kept people outside the room (in the atrium-area I mentioned before) until there was only one voter at a polling desk, so one at the desk and one in line. When the polls closed, they had a hard time shooing away the people who were not yet in line at the close of polls, so they let the lines be longer and closed the entrance doors. It took about 20 minutes after the polls closed for the last person to vote.
  • I had 179 voters at my desk, and I believe that I had the most voters of any desk in the room. (Each desk covers one neighbourhood, and I just happened to have a very civic-minded neighbourhood.)

I was happy that I was wearing a procedure mask over an N95.


This has nothing to do with COVID-19, but it’s interesting and it’s my blog: I will get paid about $400 for the three hours of training and 16.5 hours of work, so it cost a little over $2 per vote just for me. There was about one other worker for each DRO — handling registration, directing traffic, etc — plus three supervisors. So that’s about $4 per vote, even before we get into whatever management overhead there is above the supervisors, before we count the printing costs, rent, shipping, etc. So I would guess that it probably cost about $20 per vote to run this election.

Recommended Reading

This article talks about the reasons why vaccine distribution is so unequal.