Sinovac: Brazil results show Chinese vaccine 50.4% effective
Latest results show Sinovac’s Covid-19 vaccine is less effective in Brazil than previously suggested. …
A figure for efficacy is reached by looking at how many people developed Covid after being given the vaccine, compared with how many were affected when given a dummy injection. Normally, that is based on people developing obvious symptoms but in this Brazilian trial, people with no symptoms also appear to have been included.