Covid-19: BMC concludes second serological survey, results expected by next weekend
In the second comparative survey, the civic body collected blood samples of 5,840 individuals—3,700 from slums and 2,140 from non-slum areas—in the same three civic wards as the first serological surveyUpdated: Sep 04, 2020, 17:11 IST
The Brihanmumbai Municipal Corporation (BMC) concluded the second phase of a serological survey on Thursday, and results are expected by the end of next week.
In the second comparative survey, the civic body collected blood samples of 5,840 individuals—3,700 from slums and 2,140 from non-slum areas—in the same three civic wards as the first serological survey.
In a sero-survey, a group of individuals undergo blood tests to detect the presence of IgM antibodies. Immunoglobulin-G (IgM) antibodies are produced by the body’s immune system on being exposed to a foreign particle like a virus. The sero survey will help identify individuals who were previously infected with the virus and have now recovered due to the presence of antibodies.
The civic body, along with NITI-Aayog and Tata Institute of Fundamental Research (TIFR), conducted the first serological survey in July among 6,936 people living in the three wards—M-West (Tilaknagar and Chembur), F-North (Matunga, Sion and Wadala) and R-North (Dahisar and Mandapeshwar).
As many as 4,234 individuals were surveyed at random in slums, of which 56.5% were identified with Covid-19 antibodies. In non-slum areas, antibodies were prevalent in only 419 (15.5%) of 2,702 people examined.
In order to gauge the spread of the virus among the population, BMC needed to conduct the second study in the same civic wards a month after the first sero survey.
“We are expecting results of the survey within a week. The researchers will have to analyse and compare data of the first sero survey with the second one to check the change in infection rate. This will give us a clearer picture of the spread of the virus in the population and how many have remained asymptomatic,” said Suresh Kakani, additional commissioner, BMC.
As HT reported earlier, only 20% persons in non-slum residential areas cooperated with the volunteers in collecting samples in the first study. However, in comparison to the previous study, volunteers witnessed lesser resistance from non-slums individuals in the ongoing second study.
“Before starting collecting samples, we sensitized people in different societies and buildings in the same three wards so that they cooperated with us in providing their samples,” said Kakani.