Ah, the case of Israel & infections of the vaccinated. Let's see what an Epidemiologist has to offer.
"This is likely an example of
base rate bias in epidemiology (it’s called base rate fallacy in other fields). Professor Levy said that “half of infected people were vaccinated”. This language is important because it’s very different than “half of vaccinated people were infected”. And this misunderstanding happens all. the. time.
The more vaccinated a population, the more we’ll hear of the vaccinated getting infected. For example, say there’s a community that’s 100% vaccinated. If there’s transmission, we know breakthrough cases
will happen. So, by definition, 100% of outbreak cases will be among the vaccinated. It will just be 100% out of a smaller number.
Cue Israel. They are one of the
global leaders in vaccinations;
85% of Israeli adults are vaccinated. So, say we have the following scenario:
- 100 adult community
- 4 COVID19 cases
- 50% of cases were among the vaccinated
It would look something like this:
With an infection rate among the vaccinated of 2% and infection rate of 13% among the unvaccinated, this would give us an efficacy rate of 85%. This is pretty darn close to the clinical trial efficacy rate, meaning the Pfizer vaccine is still working against Delta.
https://yourlocalepidemiologist.substack.com/p/israel-50-of-infected-are-vaccinated