Source: China – South China Morning PostA study funded by Pfizer-BioNTech showed the efficacy of its Covid-19 vaccine – while still high – declined by 13 percentage points over six months after the second dose, suggesting there could be a need for booster shots in the future.More than 46,000 people in the United States, Turkey, Brazil, Argentina, South Africa and Germany were monitored for the study, which has not been peer-reviewed. Some 2,306 of the participants were aged between 12 and 15, while the rest were 16 or older. The…Read More