A medical worker inoculates a recipient with a COVID-19 vaccine at a temporary inoculation site in Haidian District in Beijing, capital of China, Jan 11, 2021.Photo:Xinhua

Experts are making further studies on whether to expand the availability of COVID-19 vaccine boosting shots to all people who have been fully vaccinated for six months, officials from China's National Health Commission told a press conference on Friday, during which they also specified three groups of people that can have the booster shots. 

Given China's good prevention situation of COVID-19, people who work at customs, border control and inspections, medical isolated sites, designated medical institutions that are high-risk for preventing imported cases, can have a booster vaccine shot six months after finishing the immunity process, Zheng Weizhong, director of the Development Center for Medical Science and Technology of the National Health Commission (NHC), told the press conference. 

As of Thursday, more than 2 billion doses of vaccines for COVID-19 have been administered in China, with nearly 900 million people on the mainland fully vaccinated, according to data from the Friday press conference. 

We found in the regular vaccination that the group with low immunity and people above 60 years old did not display the same improved immunity as people between 18 to 59 years old. But they are also the high-risk group for serious illnesses and death after being infected, Zheng said, noting that these people are also recommended to have booster vaccines. 

Experts also suggested people who need to work or study overseas get the booster shot to strengthen their immunity. 

Zheng noted that the national team on vaccine development has studied whether to expand the vaccinations of boosters. The two companies developing COVID-19 vaccines — Sinovac and Sinopharm — have conducted research on boosters and found anti-bodies decreased after finishing the entire vaccination process for six months. 

"This fits the pattern of regular vaccines," Zheng said. He noted that getting the third shot after six months is safe and antibodies quickly increased by 15 to 30 times on the 14th day of inoculation. But the anti-bodies will decrease again after another six months. 

'We thought that the protection effect of the boosters can be increased from the immunogenicity," Zheng said. 

Zheng added that vaccines have helped curb the latest epidemic flare-up. Ninety-five percent of the patients with serious illness did not get vaccinated or did not complete the immunity process.

Global Times