Gao Fu, director of the Chinese Center for Disease Control and Prevention, speaks at the China Development Forum 2021 at Diaoyutai State Guesthouse on March 20, 2021 in Beijing, China.
Han Haidan | China News Service | Getty images
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 combining them to get a boost.
Chinese vaccines “do not have very high rates of protection,” director of the China Centers for Disease Control, Gao Fu, said at a Saturday conference in the southwestern city of Chengdu.
Beijing has distributed hundreds of millions of doses overseas while trying to cast doubt on the effectiveness of the Pfizer-BioNTech vaccine created using the previously experimental messenger RNA or mRNA process.
“It is now formally considered whether we should use different vaccines from different technical lines for the immunization process,” said Gao.
Officials at a press conference Sunday did not directly respond to questions about Gao’s comment or possible changes to official plans. But another CDC official said developers are working on mRNA-based vaccines.
Gao did not respond to a phone call requesting further comment.
“The mRNA vaccines developed in our country have also entered the clinical trial phase,” said official Wang Huaqing. He did not provide a timeline for possible uses.
Experts say mixing vaccines or sequential immunization can increase effectiveness. Researchers in the UK are studying a possible combination of Pfizer-BioNTech and the traditional AstraZeneca vaccine.
The coronavirus pandemic, which began in central China in late 2019, is the first time the Chinese drug industry has played a role in responding to a global health emergency.
Vaccines made by private company Sinovac and state-owned Sinopharm make up the majority of Chinese vaccines distributed to several dozen countries, including Mexico, Turkey, Indonesia, Hungary, Brazil and Turkey.
The effectiveness of a Sinovac vaccine in preventing symptomatic infections was found by researchers in Brazil to be only 50.4%, close to the 50% threshold at which health experts say a vaccine is useful. In comparison, the Pfizer BioNTech vaccine has been shown to be 97% effective.
Health experts say Chinese vaccines are unlikely to be sold to the United States, Western Europe and Japan due to the complexity of the approval process.
A Sinovac spokesperson, Liu Peicheng, acknowledged that varying levels of effectiveness have been found, but said it could be due to the age of the people in a study, the virus strain and other factors.
Beijing has not yet approved foreign vaccines for use in China.
Gao did not provide details on possible changes in strategy, but mentioned mRNA as a possibility.
“Everyone should consider the benefits mRNA vaccines can have for mankind,” said Gao. “We have to monitor it carefully and not ignore it just because we already have different types of vaccines.”
Gao previously questioned the safety of mRNA vaccines. He was quoted by the official Xinhua News Agency as saying in December that he couldn’t rule out negative side effects because they were first used in healthy people.
Chinese state media and popular health and science blogs have also questioned the safety and effectiveness of the Pfizer-BioNTech vaccine.
On April 2, about 34 million people in China received both doses needed for Chinese vaccines and about 65 million received one, Gao said.
Sinovac spokesperson, Liu, said studies find protection “may be better” if the time between vaccinations is longer than the current 14 days, but gave no indication that this could be made standard practice.