China CDC director worries about ‘not high’ vaccine efficacy, but says his remarks were taken out of context

Science & Health

Gao Fu, the director of China’s CDC, suggested mixing vaccines, adding doses, and looking into mRNA technology to improve the efficacy of COVID-19 shots. He later insisted that he wasn’t “admitting” to a low effectiveness of Chinese vaccines.

Illustration by Derek Zheng

Since at least last November, it has been widely known that China’s COVID-19 vaccines are not likely to be as effective at preventing symptomatic disease as some other vaccines, such as those made by Pfizer and Moderna.

  • Preliminary data from Brazil, one country where Sinovac Biotech is testing its vaccine, indicated that the shot had just over 50% efficacy in reducing the risk of infection.
  • That number for Sinovac has been recently confirmed by real-time data in Chile.
  • Another leading Chinese vaccine, made by Sinopharm, reported an efficacy rate above 70%.
  • These efficacy numbers are not significantly different from the shots made by AstraZeneca or Johnson & Johnson — generally between 65% and 80%, depending on the study — but are below the level for Pfizer and Moderna, which prevent more than 90% of infections.
  • It should be noted: Any vaccine with more than 50% effectiveness is considered good for regulatory approval, and even the “less effective” vaccines still prevent nearly all cases of severe disease.

But the Chinese government clearly dislikes the perception that China-made vaccines are inferior, and has launched disinformation campaigns to undermine confidence in non-Chinese vaccines.

So China’s CDC director Gāo Fú 高福 put his foot in his mouth on April 10 when he said (in Chinese) that the efficacy of “current vaccines” are “not high.”

  • Gao reportedly “proposed mixing different vaccines as well as amending the sequence of doses, such as changing the number and quantity of doses, and the interval between them,” to increase their effectiveness, per the Financial Times.
  • He also “praised the benefits of mRNA vaccines, the technology behind the two vaccines seen as the most effective, Pfizer-BioNTech and Moderna, months after questioning whether the then-unproven method was safe,” the AP notes.
  • The comments “appeared inadvertent and quickly spread through Chinese social media on Saturday before being mostly censored,” the Washington Post reports.

Gao claimed that he had been misquoted by media as “admitting” a low efficacy of Chinese vaccines. He gave interviews on April 11 to multiple Chinese outlets to make a broader argument about his “scientific vision”:

  • “It was a complete misunderstanding,” Gao told the Global Times tabloid (in English, Chinese). “The protection rates of all vaccines in the world are sometimes high, and sometimes low. How to improve their efficacy is a question that needs to be considered by scientists around the world,” he added.
  • “Immunization programs are dynamically changing around the world,” Gao told Guancha (in Chinese). “France has already delayed the two doses of the mRNA vaccine from four weeks to six weeks.”

How might this impact Chinese vaccine rollouts?

In brief: