Gao Fu, director of the Chinese Center for Disease Control and Prevention, speaks at the 2021 China Development Forum at the Diaoyutai State Pension 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 chief disease control official says their effectiveness is low and the government plans to mix them up to get a boost.
Chinese vaccines “do not have very high protection rates,” Gao Fu, director of China’s Centers for Disease Control, told a conference in the southwestern city of Chengdu on Saturday.
Beijing has distributed hundreds of millions of doses abroad, trying to promote doubt about the effectiveness of the Pfizer-BioNTech vaccine made using the previous experimental messenger RNA or mRNA process.
“It is now being formally examined whether we should use different vaccines from different technical lines for the immunization process,” Gao said.
Officials at a news conference on Sunday did not directly answer 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 answer a phone call for further comment.
“The mRNA vaccines developed in our country have also entered the stage of clinical study,” said official Wang Huaqing. He did not give any chronology for a possible use.
Experts say mixing vaccines or sequential immunization could 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, marks the first time the Chinese drug industry has played a role in responding to a global health emergency.
The vaccines produced by Sinovac, a private company, and Sinopharm, a state-owned company, accounted for most of the Chinese vaccines distributed in dozens of countries, including Mexico, Turkey, Indonesia, Hungary, Brazil and Turkey.
The effectiveness of a Sinovac vaccine in preventing symptomatic infections has been shown to be up to 50.4% by researchers in Brazil, close to the 50% threshold at which health experts say a vaccine is useful. By 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 because of the complexity of the approval process.
A Sinovac spokesman, Liu Peicheng, acknowledged that different levels of efficiency were found, but said that this may be due to the age of the people in a study, the strain of the virus and other factors.
Beijing has not yet approved any foreign vaccine for use in China.
Gao did not provide details on possible strategy changes, but cited mRNA as a possibility.
“Everyone should consider the benefits that mRNA vaccines can bring to humanity,” Gao said. “We need to follow it closely and not just ignore it because we already have several types of vaccines.”
Gao has previously questioned the safety of mRNA vaccines. He was quoted by the official Xinhua news agency as saying in December that he could not rule out negative side effects because they were first used on healthy people.
Chinese state media and popular health and science blogs have questioned the safety and effectiveness of the Pfizer-BioNTech vaccine.
As of April 2, about 34 million people in China have received both doses of Chinese vaccines and about 65 million have received one, according to Gao.
Sinovac spokesman Liu said the studies believe that protection “can be better” if vaccination time is longer than the current 14 days, but did not indicate that it could be standard practice.