Efficacy of a coronavirus vaccine from Sinovac has been found to be as low as 50.4 percent by researchers.
In a rare admission of the weakness of Chinese coronavirus vaccines, the country’s top disease control official says their effectiveness is low and the government is considering mixing them to give them a boost.
Chinese vaccines “don’t have very high protection rates”, said the director of the China Centers for Disease Control, Gao Fu, at a conference on Saturday in the southwestern city of Chengdu.
Beijing has distributed hundreds of millions of doses in other countries.
“It’s now under formal consideration whether we should use different vaccines from different technical lines for the immunisation process,” Gao said.
The effectiveness rate of a coronavirus vaccine from Sinovac, a Chinese developer, at preventing symptomatic infections has been found to be as low as 50.4 percent by researchers in Brazil. By comparison, the vaccine made by Pfizer-BioNTech has been found to be 97-percent effective.
Beijing has yet to approve any foreign vaccines for use in China, where the coronavirus emerged in late 2019.
Gao gave no details of possible changes in strategy but mentioned mRNA, a previously experimental technique used by some Western vaccine developers while China’s drug-makers used traditional technology.
“Everyone should consider the benefits mRNA vaccines can bring for humanity,” Gao said. “We must follow it carefully and not ignore it just because we already have several types of vaccines already.”
Gao previously raised questions about the safety of mRNA vaccines. He was quoted by the official Xinhua news agency as saying in December he could not rule out negative side effects because they were being used for the first time on healthy people.
Chinese state media and popular health and science blogs also have questioned the safety and effectiveness of the Pfizer-BioNTech vaccine, which uses mRNA.
As of April 2, some 34 million people have received the two doses required by Chinese vaccines and about 65 million received one, according to Gao.
Experts say mixing vaccines, or sequential immunisation, might boost effectiveness rates. Trials around the world are looking at mixing vaccines or giving a booster shot after a longer time period.
Researchers in Britain are studying a possible combination of the Pfizer-BioNTech and AstraZeneca vaccines.