(Yicai Global) Feb. 13 -- Covid-19 antibody tests can help people at high risk of infection, such as the elderly and those with underlying health issues, decide whether or not to get vaccinated, according to an expert.

People who have had the novel coronavirus and no longer have the antibodies should get vaccinated to avoid being re-infected, said Prof. Jin Dongyan, a virologist at the School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, at the University of Hong Kong. Nursing homes should take charge of the vaccination process for the elderly, Jin added.

Medical centers in Shenzhen, Beijing, Ningbo and other Chinese cities have started to provide Covid-19 antibody testing services, which check for the presence of the immunoglobulin M and immunoglobulin G antibodies. IgM will gradually disappear from a week after it was produced, but IgG can last for months.

People with a high risk of exposure, such as doctors and therapists, should also take the antibody test as a reference point, Jin noted.

Mass antibody testing campaigns can be useful to draw conclusions on vaccines and make more accurate judgments, an expert at an infectious disease hospital told Yicai Global. For example, China could arrange the next round of jabs based on which shot or vaccine combination can produce more antibodies or which can prompt antibodies that remain in the body for longer, the person said.

China’s National Medical Products Administration has approved 41 commercially available Covid antibody detection kits which can produce results in 10 to 20 minutes. But most can only show that antibodies are present, not their quantity. 

Editor: Futura Costaglione