By Staff Reporters

China's COVID-19 vaccines arrived at Philippine airport (PHOTO: XINHUA)

China has provided more than 800 million doses of COVID-19 vaccine to the world, most notably to developing countries, many of which have carried out large-scale vaccination campaigns.

Zheng Zhongwei, director of the Development Center for Medical Science and Technology of the National Health Commission (NHC), and head of the national working group for vaccine development, presented this information at a media briefing on August 27.

Zheng said that the details of the vaccine's efficacy can vary due to many factors. For example, various countries adopt diverse prevention and control strategies. In general, the latest academic report on the vaccine revealed that large-scale real-world data in Peru, Thailand, Chile, Argentina and other countries, proves China-developed inactivated vaccine has a protection rate against symptomatic infection ranging from 57 to 85 percent and 90 percent against severe cases. As to the prevention of COVID-19-related death, the rate ranges from 84 to 97 percent.

It can be said that international real world studies show that China's COVID-19 vaccine is indeed effective in infection prevention and significantly preventing severe disease and death.

A study in Chile, for example, shows China's CoronaVac vaccine effectively prevented COVID-19 there, with the adjusted vaccine effectiveness reaching 90.3 percent for the prevention of severe disease, according to a study published in the New England Journal of Medicine. A nationwide mass vaccination campaign was conducted from this February 2 to May 1, that included a cohort of more than 10 million people. The adjusted vaccine effectiveness was 65.9 percent for the prevention of COVID-19, 87.5 percent for the prevention of hospitalization, and 86.3 percent for the prevention of COVID-19-related deaths, the results of the study showed.

Sri Lanka also officially released a research report on inactivated vaccines of the Sinopharm Group, showing that they can not only stimulate humoral immunity, but also induce immune responses of T cells and memory B cells.