I’m seeing lots of confusion around the frequency of breakthrough cases and the effectiveness of vaccines (in fact, a recent interview I did resulted in a confusing headline on this topic!) so let’s dive in! Vaccine effectiveness is a relative measure, it tells us how protected you will be relative to an unvaccinated person. Even with delta, this looks ok for infections (and very good for severe illness) Scenario 1: 🤒 if an unvaccinated person has a 10% chance of getting sick 💉 and ...
