Special: Battle against the new coronavirus
Zhong Nanshan, China’s top respiratory disease expert, said Thursday that in theory China has built up some level of herd immunity since more than 83% of the country’s population has been vaccinated.
He made these remarks during a forum in Guangzhou, in the province of Guangdong (south of China).
Herd immunity could be achieved when a certain part of the population is vaccinated, Zhong said, urging more Chinese residents to take booster shots.
China launched its vaccination program starting with high-risk groups in December 2020.
Data released by the National Health Commission shows that more than 1.2 billion people on the Chinese mainland have been fully immunized as of December 28, 2021, representing more than 85.6% of the country’s population. .
When the majority of a population is immune to an infectious disease, it provides indirect protection or population immunity, also known as herd immunity or collective protection, to those who are not immune to the disease, according to a report by the Bloomberg School of Public Health at Johns Hopkins University.
Depending on how contagious an infection is, 50 to 90 percent of the population typically need immunity before infection rates start to drop, according to the report.
As for the SARS-CoV-2 virus that causes COVID-19, the figure proposed by many epidemiologists at the start of the pandemic was 60 to 70%. But the threshold continues to be pushed back by epidemiologists as the pandemic worsens and the virus mutates into more transmissible variants.
Senior U.S. pandemic adviser Anthony Fauci told media in December 2021 he believed it might take nearly 90% immunity to stop the virus.