BEIJING • People who have received Covid-19 vaccines will likely be protected from the disease for more than half a year, a senior Chinese health official said, citing findings from animal testing, clinical trials and medical follow-ups.
Animal tests conducted since February have shown that vaccinated monkeys exposed to the coronavirus have been protected from infection, Global Times reported Dr Zeng Yixin, deputy director of China's National Health Commission, as saying on Saturday.
Antibodies remain present in people involved in China's phase two clinical trials launched in March, and hospital follow-ups on recovered Covid-19 patients also found the antibodies in some patients for up to 10 months, he said.
But the Covid-19 vaccine is unlikely to render one immune to the disease for life, said Dr Yang Zhanqiu, deputy director of the pathogen biology department at Wuhan University.
"The human body's immunity for the flu virus is generally about one year, so we have to get the vaccine every year," Dr Yang told Global Times.
Similarly, it is believed that the body's immunity to coronaviruses lasts for two to four years, so people may have to get revaccinated a few years later, he said.
China has already administered over one million Covid-19 vaccines since July and plans to distribute more, initially targeting workers in industries where there are higher risks of infection, as it seeks to be at the vanguard of the global Covid-19 immunisation effort.
Vaccines developed by Sinovac Biotech and the state-owned China National Biotec Group (CNBG) have been dispensed in China since they were granted emergency-use authorisation.
Dr Zeng said China is now planning wider distribution of the experimental shots, with those working in hospitals, Customs, public transport and cold-chain logistics as well as vulnerable groups to receive them first.
"Prioritising them in immunisation will not only protect them against the risk of the virus, but also aid the country's efforts to prevent a resurgence of the virus and fend off risks from overseas," Dr Zeng said, adding that a later phase of the roll-out will involve the general public.
"Our goal is to achieve herd immunity through proactive immunisation and curb the disease more effectively as soon as possible."
The one million figure refers to the number of doses administered, and not the people inoculated.
CNBG chairman Yang Xiaoming said recently that more than 650,000 people had been vaccinated with Chinese vaccines.
Both CNBG and Sinovac's candidates follow a two-shot regimen.
CHINA DAILY/ASIA NEWS NETWORK, BLOOMBERG
