A Serological survey conducted by a team of the BMC’s  health department and doctors from medical colleges across the city has revealed the presence of antibodies in more samples taken from public laboratories as compared to those from private ones. This points at a trend that lower-middle class and middle-class, mainly residing in slums and chawls, have higher antibodies than those staying in high-rises. 

The civic body had collected about 12,000 samples (6,000 each) from public laboratories — where COVID-19 tests are free for all, and private laboratories — where a charge is taken for the tests. The primary report of the survey shows that 46 per cent of the samples collected from public labs have antibodies whereas, only 22 per cent of the samples from private labs have antibodies. A senior civic official said that this pointed at the trend that those living in slums and chawls were mainly undergoing tests at public laboratories and had higher antibodies than those residing in buildings.