BENGALURU: While most healthcare workers are demanding a booster dose, an antibody test conducted on healthcare personnel at Jayadeva Institute of Cardiovascular Sciences and Research, revealed that their antibodies had not waned even six months after taking the second dose. This raises questions on the need for a booster dose, or third dose, six months after the second dose.
The Department of Microbiology conducted blood tests for IgG neutralising antibody level by the Elisa method on 250 healthcare workers, who had received two doses of Covishield vaccine in February 2021. According to Jayadeva Hospital Director Dr C N Manjunath, 80% of the same group of healthcare workers showed good antibody response in the study conducted in April 2021.
“When antibody tests were repeated on the same group of workers, 99% showed positive antibody response,” he told TNSE. He said the kits used for test reference cut-off values of antibody levels more than 30% is considered as positive immune response, and 20% of workers who initially did not have a positive immune response in April showed a significant improvement in antibody levels in September 2021.
“They are called ‘delayed responders’. Of these 250 workers, 19 who were Covid-infected and had taken vaccines showed the highest antibody response. Although 10 workers showed a decline in antibody levels from April to September, they remain in the positive immune response limit (4%),” he added.