I have been reading news about people getting infected with COVID-19 despite getting the AstraZeneca vaccine.

I am not sure if it's similar with other vaccines.

May I ask which vaccines have zero (preferably) cases of people getting infected after jabbing with that vaccine? The least would be equally good. I'm interested in American, European, and Russian vaccines. Other countries are fine as well, except China because I have heard they don't publish real information and the government there controls the media.


No vaccine in history has ever been 100% effective. It's not reasonable to expect it.

All of the vaccines being distributed for which data are public are highly effective, though. This Q&A over at Biology.SE explains how "efficacy" is calculated in the trials: https://biology.stackexchange.com/questions/96941/what-does-vaccine-efficacy-mean

Generally the higher efficacy numbers have been around 95% for symptomatic illness, and even more effective at preventing severe illness (hospitalization, death) than preventing symptomatic illness.

Even if something is 99.9% effective, someone can write a news article about the cases in the 0.1%. These news reports are not a good basis to make decisions on. 95% efficacy means you are 95% less likely to get sick. That's a good thing.

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