The report of the second round of serological survey, conducted in the second half of August in three wards of Mumbai, shows around 45 per cent of slum population and 18 per cent of non-slum residents have developed antibodies. A serological survey is conducted to check the prevalence of antibodies against the infection in recovered patients.

In the first round, seroprevalence was found in an estimated 57 per cent population in slums and 16 per cent in non-slum areas. In the first round, 6,936 samples were collected from slums and non-slum areas of three wards — R/N (Dahisar), M/W (Chembur) and F/N ward (Wadala and Sion).