Pfizer Vaccine 90% Effective – What Does That Mean?

The big news today was that Pfizer announced that its COVID-19 vaccine is 90% effective. Is this 90% of all vaccinated do not get COVID-19? Does this include those with pre-existing conditions? Pfizer Announcement https://www.webmd.com/lung/news/20201109/pfizer-says-covid-vaccine-90-effective Pfizer is seeking emergency use … Continue reading