Covid-19 antibodies were present in 99.93% of samples taken from healthcare and frontline workers in Mumbai, PTI reported, citing the findings of the quantitative sero survey conducted in March by the city’s civic body.

The Brihanmumbai Municipal Corporation examined 3,099 participants, of whom 3,097 were found to have antibodies. The civic body also said that 15.9% of the total participants had tested positive for Covid-19 since the start of the pandemic.

More antibodies were found in the blood samples of 36.5% of the employees who had taken the Covid vaccination doses.

“Of the 3,099 health and frontline workers, 726 employees were nurses and health workers from primary health centres in 24 wards of the BMC, 776 were Brihanmumbai Electric Supply and Transport staffers and 779 were from solid waste management department, among others,” it said.

The Brihanmumbai Municipal Corporation said it was the first quantitative survey conducted to make decisions about vaccination based on data gained from the respondents, PTI reported.

A sero survey tests a sample population in a region to assess whether it has antibodies against a particular infection. The presence of antibodies indicates that people may have been exposed to the infection even if they had not developed symptoms of the disease.

This was the sixth regular sero survey.

In the next six months, the Mumbai civic body will conduct a second quantitative sero survey to check the level of antibodies in blood samples of the same participants, PTI reported.