Covishield cover high 7 months after 2 doses, 90% antibody prevalence seen: Study

PUNE: High levels of protection (seroprevalence) against Covid-19 have been detected in over 500 healthcare workers even three to seven months after taking two doses of Covishield, a recent analysis by Pune-based BJ Government Medical College (BJMC) and Sassoon hospital has revealed.

With high levels of protection (seroprevalence) in participants at this point, the study concluded that a third booster, while a chunk of population is yet to get their second shots, may not be advisable, Dr Muralidhar Tambe, professor and Head of Community Medicine at BJMC, told TOI.

The study also found that in all categories of the 558 healthcare workers (HCWs), who were part of the study, the antibody prevalence was above 90% months after completion of two vaccine doses.

Dr Tambe said, “Though we found that the antibody prevalence decreased as the duration of interval increased after two doses of Covid vaccine, immunity levels remained high. Antibody positivity among the study participants was at 96.77% at three months post full vaccination, rising to 100% at four months, and then falling to 91.89% at seven months after the initial two doses.”

Dr Tambe said overall, of the 558 HCWs who participated in the study, 94.4% were positive for Covid neutralising antibodies at the time of the study period.