Vaccine Effectiveness Hits as Low as Minus-66% in the Over-40s, New PHE Data Shows

“…The new Public Health England (PHE) Vaccine Surveillance report was released on Thursday, allowing us to update our estimates of unadjusted vaccine effectiveness from real-world data.

Oddly, the report appeared on a new webpage this week, but the old page didn’t include a note to let you know, so it took me a while to discover it had appeared and where it was.

Following last week’s ‘fact check‘ from Full Fatuous – ostensibly of my piece but with some words of admonition for PHE as well, particularly over the accuracy of the population data – a new note appeared in the report: “Interpretation of the case rates in vaccinated and unvaccinated population is particularly susceptible to changes in denominators and should be interpreted with extra caution.” So there you go. All estimates in this post are based on the data PHE uses and are valid insofar as that data is accurate.

As before, the data is just for a four-week period, which, given that the early part of the Delta surge was dominated by the unvaccinated and the latter part has seen infections rise in the vaccinated, seems to me a mistake. A fairer view would cover the whole Delta surge (as with the estimates I make from the data in the Technical Briefings), but in any case the report gives a snapshot of current relative infection rates…”