Chinese experts: Chinese vaccines “prevent disease” not “prevent infection”

Chinese CDC expert Shao Yiming said on 8 August that the Chinese vaccine is positioned to “prevent disease” rather than “prevent infection” and that the possibility of infection still exists after vaccination. Experts pointed out that the current new vaccines are approved based on their effectiveness in preventing symptoms rather than preventing infection, and some experts believe that the World Health Organization approved the Chinese vaccine for the sake of “having it first and then getting it right.

Shao Yiming, a researcher at the Chinese Center for Disease Control and Prevention and an advisor to the World Health Organization’s Vaccine Research and Development Committee, replied to Chinese media during the second session of the Boao Forum for Asia Global Health Forum, saying that China’s new crown vaccine is positioned for secondary prevention, and the rate of protection is against disease onset rather than infection, “so there will be some people who may be infected even after vaccination. “

According to the Daily Economic News, Shao Yiming explained that the protection of the vaccine is divided into three levels, the most ideal primary prevention is “anti-infection”, which can protect the vaccinated person from infection; secondary prevention is “anti-morbidity” or Secondary prevention is “protection against morbidity” or “protection against serious illness”, so that minor illnesses do not turn into serious illnesses and lead to death; and tertiary prevention is “protection against transmission”, which means that even if one is infected, the amount of virus in the body is low and it is difficult to transmit to others.

Jennifer Huang Bouey, an epidemiologist at the RAND Corporation, a U.S. think tank, explained to the station, “The primary endpoints of vaccine clinical trials are all symptom-specific for the new coronavirus, so at this stage, all decisions to approve vaccines are based on effectiveness in preventing symptoms, not in preventing infection (from being effective). “

However, China’s Guangdong Province is currently facing a new wave of outbreaks, with the Daily Beast reporting four patients who received their first dose of the neo-coronavirus vaccine and have yet to receive their second dose. According to the U.S. Centers for Disease Control and Prevention (CDC), it usually takes about 2 weeks after vaccination to establish protection, but there are still a few “breakthrough cases” of infection after vaccination, according to the CDC’s New Coronavirus Vaccine Release. According to the latest data on “breakthrough cases,” there were only 10,262 breakthrough infections among the 101 million people who had completed vaccination by the end of April.

Huang Zhihuan said, “Relatively high population re-coverage is required to obtain herd immunity when vaccine efficacy is relatively low, and outbreaks are still possible until herd immunity is reached.”

In Guangdong Province, 114 new cases of New Coronavirus pneumonia were reported between May 26 and June 5, all of which were mainly infected with the Indian variant of the virus. In addition to universal nucleic acid testing by authorities in several cities, Guangdong Railway also announced upgraded departure control measures from June 7, with travelers required to present negative nucleic acid test results within the required time frame before they can travel on trains.

Prior to this, Shao Yiming revealed that China is developing a new generation of vaccine for the new crown variant virus, and Yin Weidong, chairman of China Tech Holdings, also revealed on the 4th that Chinese officials have approved the extension of the age range for emergency use of the Tech Holdings vaccine to minors over 3 years old.

China is currently promoting the new vaccine, but the number of confirmed cases is still soaring in countries where a large number of Chinese vaccines are administered. According to Reuters, the UAE and Bahrain, where the number of infections has risen again recently, have begun offering a “third dose” of the Pfizer vaccine as a booster for residents who have received the Chinese vaccine.

Despite doubts about the efficacy of the Chinese vaccine, the World Health Organization has recently granted emergency authorization for the use of the China National Drug and Kexing vaccines. In the eyes of He Anquan, who graduated from Shanghai Second Medical University and now practices medicine in New York, it’s a “seek first, then get better” mentality.

“It is true that there are many countries that do not have immediate access to advanced vaccines, and WHO believes that it is better to have than not to have, so that these countries can use the vaccine first, and not to say how effective it is, good or bad.”

In its response to our inquiry, WHO only reiterated that the conditions for the approval of vaccines to enter the Emergency Use Listing (EUL) are assessed to include vaccine quality, safety and efficacy, risk management plans, and requirements for low temperature in transport and storage. The Chinese vaccine is an inactivated vaccine that requires only routine cryopreservation, which facilitates transportation, storage, and safekeeping, and is beneficial to countries with less favorable medical conditions and more backward conditions, and has been authorized for emergency use in dozens of countries worldwide.