Image: Reuters Berita 24 English - After two doses of a Sinopharm COVID-19 vaccine, neutralising antibodies against several Omicron sub-v...
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| Image: Reuters |
Berita 24 English - After two doses of a Sinopharm COVID-19 vaccine, neutralising antibodies against several Omicron sub-variants were largely undetectable, with a booster shot only partially restoring them, according to a small Chinese study published in The Lancet Infectious Diseases journal.
The study comes as China works to raise vaccination rates, retaining a "dynamic zero COVID" strategy aimed at eradicating all outbreaks while many countries have taken a "learn to live with the virus" approach.
BBIBP-CorV is one of two Sinopharm COVID shots approved for usage in China, as well as the principal shot exported by the state-owned company.
The neutralising action against sub-variants like BA.2.12.1 and BA.4/BA.5 was "not or only barely detectable" among 25 people who received two doses of BBIBP-CorV vaccination, according to researchers in a letter published on Monday.
According to the researchers, neutralising activity against certain sub-variants was seen in only 24-48 percent of subjects who had a BBIBP-CorV booster shot following the two-dose product, based on results from a group of 25 people.
According to data from another set of 30 individuals, the rate improved marginally, to 30-53 percent, for those who received a third shot prepared by a unit of Chongqing Zhifei Biological Products, another vaccine approved for use in China.
The boosters' efficacy, which is measured in major clinical trials and represents how well they can reduce the risk of COVID disease or death, was not discussed in the study.
