China’s COVID-19 Vaccines , ‘Don’t Have Very High Protection Rates’ .br The director of the China Centers for br Disease Control, Gao Fu, revealed the news br on Saturday at a conference in Chengdu.br Gao also shared that the government is considering br mixing vaccines to boost effectiveness.br It’s now under formal br consideration whether we br should use different vaccines .., Gao Fu, via conference.br ... from different technical lines br for the immunization process, Gao Fu, via conference.br Another China CDC official said mRNA-based br vaccines have entered clinical trials, though br he did not provide a timeline.br The Sinovac and Sinopharm vaccines make up the majority of Chinese vaccines, with the former found to be as low as 50.4 effective in preventing serious infections.