In today's environment, the covid vaccines are bei

In today's environment, the covid vaccines are being tested against a large caliber machine gun.

Consider the measles vaccine, which seems to largely have gotten rid of measles.

A couple years ago there was a flareup at Disneyland California. About 400 Disneyland visitors were acquired measles.

A curious result of this infection was that roughly half of the stricken were unvaccinated and half were vaccinated.

If you google "measles vaccine efficacy" or similar you will find that it is generally describe as around "95% effective". I am not sure that there has every been a large clincal trial that tried to detect the efficacy of the measles vaccine, but that's what the google search says.

Another thing you can get pretty quick from google is that roughly 5% of the US population is not vaccinated for measles.

Well, if the ratio of vaccinated to unvaccinated at Disneyland was 20:1 and the effectiveness of the vaccine was 20:1, then when you run the experiment at Disneyland you will get 1:1 measles-vaccinated versus measles-unvaccinated, which is about the actual result.

It is generally not possible to run controlled vaccine experiments on humans for vaccines.

Except for two cases that I can think of: Disneyland and covid19.

My point is that the measles vaccine, generally thought of as 95% effective, controls measles very effectively when the measles virus is very uncommon in the environment.

Today, the covid virus is very common in the environment and yet the clinical trials achieved 95% effectiveness.

I would say that covid vaccine effectiveness is achieved against a high caliber machine gun rather than the measles vaccine effectiveness achieved agains a small caliber one shot.

Of course we really don't know how effective the covid vaccines because it is still early.

But if the 20:1 ratio of covid-unvaccinated to covid vaccinated holds, I expect the covid vaccines to control covid very effectively.