A new real world studyreviewing the efficacy of the CoronaVac vaccine from Sinovac Biotech Ltd., a Beijing-based developer, could fuel fresh doubts about the effectiveness of Chinese COVID-19 vaccines.
The study, unveiled on 7 April by preprint website Medtrxiv.com and not peer-reviewed, focused on the region of Manaus, an Amazonian city that has seen the pandemic spread out of...