On and on we go. No briefing yet this week from our friends at the Mn DOH. Not sure why. We may be on the cusp of wave of some sort, with lots of vaxed cases. Deaths are strangely up a lot and I am betting that is a lot of vaxed old people. September this year has now passed last year at this time in deaths by quite a bit.
We are going to be inundated with papers on vaccine effectiveness. This one was done among health care workers in 25 states. That group was vaxed early, so a longer followup is available. This is another paper to suggest that Moderna might be slightly more effective than Pfizer, but both showed very good initial effectiveness against infection. Both vaccines appeared to show lessening effectiveness against infection after a few months. They were also less effective in those over 50. (NEJM Study)
And this study is the final report on the blinded stage of the pivotal trial of the Moderna vaccine, showing particularly high effectiveness in preventing serious disease. (NEJM Article)
This is a meta-review of studies assessing immunity following infection versus vaccination. Nine studies were included, ranging from moderate to high quality. The conclusion is that the evidence to date suggests that natural adaptive immunity is at least as good as that from vax, and also that vax after infection may increase protection even further, but isn’t really necessary. (Medrxiv Paper)
This CDC study studied an outbreak in a prison where most people were vaxed. 81% of the prisoners were vaccinated (for some reason, not much data on staff who were also involved in the outbreak, although we do learn that a very small 3% of staff tested positive, only 1% of whom worked in the affected prison wings). 74% of the prison population became infected, with this occurring in 90% of the unvaxed population and 70% of the vaxed, so not actually very high effectiveness against infection, but also remember how over-sensitive PCR tests are. 4 prisoners were hospitalized, three of those were unvaxed, while one was vaxed, so much better effectiveness against serious illness, and one death occurred in an unvaxed inmate. The lowest attack rate was in those with prior infection and vaccination. Those vaxed more recently had a lower attack rate. Culture positivity was similar among the two groups. Please note: masking was mandatory and enforced, made no f***ing difference. All Delta cases by the way. (CDC Study)
A CDC study also compared the effectiveness of Pfizer and Moderna and Janssen vaccines in regard to preventing hospitalizations. Moderna won at 93%, Pfizer came in at 88% and Janssen is a laggard at 71%. (CDC Study)
This paper was nominally on the impact of vaccination on state case rates, but a variety of other factors were also analyzed. What caught my eye was the finding that strictness of mitigation measures, i.e., lockdowns, was not associated with case rates. Vax rates were inversely associated with case rates, that is, more vaxed people equaled less cases. Population density was associated with more cases. One missing important variable, however, which might be a significant confounder, is geographic seasonality. (SSRN Paper)