In Mumbai, antibodies have been found in 99.93 per cent  of healthcare workers (HCW) and frontline workers (FLW). The serosurvey report also states that the levels of antibodies were relatively high in those who have taken the booster dose. To know the Seropositivity rate for SARS CoV-2 IgG antibodies among HCW and FLW and to understand the effect of vaccination and natural infection on antibody levels, BMC conducted a sixth serosurvey.

This was the first survey to quantify antibody levels. Of the 3,099 samples, antibodies have been found in 3,097. From the primary health set-up, 726 samples were collected across 24 wards and 632 samples were collected from doctors, nurses, and Class IV workers at the 15 peripheral and two special hospitals. In addition, 776 samples were collected from BEST from 25 depots and 779 samples were collected from Solid Waste Management workers from all wards. Overall 50.1 per cent were frontline workers and 49.9 per cent were HCW.