A sero survey by Mumbai's civic body has found that women have more antibodies than men to fight the coronavirus.
It also showed that sero positivity in non-slum areas was increasing, while it was decreasing in slum areas, which matches the current trend that a large number of patients are being detected from the former in the current Covid-19 surge, officials said.
Sero positivity entails a blood test showing a positive result for a particular antibody, a civic official explained.
The Brihanmumbai Municipal Corporation survey, details of which were revealed on Saturday, showed sero positivity among women was 37.12 per cent as against 35.02 per cent in men.
"In the sero survey, 41.61 per cent sero positivity was found in blood samples taken from municipal dispensaries in slum areas. Overall, 36.30 per cent sero positivity is found in 10,197 blood samples collected from citizens from all 24 wards in Mumbai," it said.
"The samples were tested for antibodies in BMC's molecular biology laboratory in its Kasturba Hospital premises. The first survey in July last year had found 57 per cent sero positivity in slum areas of three wards, while the one in August showed 45 per cent sero positivity in slum areas," an official said.
"Blood samples taken from private laboratories in non-slum areas showed sero positivity of 28.5 per cent in the current survey. In the first survey conducted in July last year, this figure was 16 per cent for three wards and 18 per cent in the one held in August," he added.
The sero survey, held in March this year, was carried out using the "unlinked anonymous sampling method" with blood samples collected from those who had not been vaccinated, and was the third after similar exercises in July and August last year, a BMC release said.