A more detailed overview: https://theconversation.com/covid-19-vaccine-faq-6-things-to-look-for-in-clinical-trial-results-150843 https://theconversation.com/co

A more detailed overview: https://theconversation.com/covid-19-vaccine-faq-6-things-to-look-for-in-clinical-trial-results-150843 https://theconversation.com/covid-19-vaccine-faq-6-things-to... You'd have to look at the registered study details for the full protocol. See this BMJ article for references: BMJ 2020;371:m4058 | doi: 10.1136/bmj.m4058 It doesn't prevent herd immunity if it only prevents the disease (i.e illness) but it makes it very difficult to achieve strong suppression if there is vaccine hesitancy (a polite grab bag term for science denialism, people who watch Fox, loopy muffin brain people, etc) above 20%. Which there will be in many parts of the US and Europe because of years of uncontested bullshit. (Thanks Facebook.)