Chinese vaccines “don’t have very high protection rates,” said the director of the China Centers for Disease Control, Gao Fu, at a conference Saturday in the southwestern city of Chengdu, according to AP News. Beijing has distributed hundreds of millions of doses abroad while trying to promote doubt about the effectiveness of the Pfizer-BioNTech vaccine made using the previously experimental messenger RNA, or mRNA, process.
Gao Fu, director of the China Centers for Disease Control, speaks at the National Vaccines and Health conference in Chengdu in southwest China's Sichuan province Saturday, April 10, 2021. In a rare admission of the weakness of Chinese coronavirus vaccines, Gao the country's top disease control official says their effectiveness is low and the government is considering mixing them to give them a boost. (Chinatopix Via AP) “It’s now under formal consideration whether we should use different vaccines from different technical lines for the immunization process,” Gao said.
Officials at a news conference Sunday didn’t respond directly to questions about Gao’s comment or possible changes in official plans. But another CDC official said developers are working on mRNA-based vaccines.
Experts say mixing vaccines, or sequential immunisation might boost effectiveness. Researchers in Britain are studying a possible combination of Pfizer-BioNTech and the traditional AstraZeneca vaccine.
The effectiveness of a Sinovac vaccine at preventing symptomatic infections was found to be as low as 50.4% by researchers in Brazil, near the 50% threshold at which health experts say a vaccine is useful. The Pfizer-BioNTech vaccine has been found to be 97% effective.
A Sinovac spokesman, Liu Peicheng, acknowledged varying levels of effectiveness have been found but said that can be due to the age of people in a study, the strain of the virus and other factors.