New Delhi | Jagran News Desk: A sero-surveillance study done in Mumbai has revealed that around 57 per cent of the total population living in the slum area and around 16 per cent of the population living in the non-slum residents in 3 civic wards of Mumbai had developed antibodies for the coronavirus, indicating that a large number of the population have already been exposed to the deadly virus than the official tally suggest.

The serosurvey in Mumbai was started on June 3, and 6,936 samples out of an estimated 8,870 were collected from slum and non-slum population of three civic wards - R-North, M-West and F-North - in the first half of July. The survey was jointly commissioned by NITI Aayog, the BMC and the Tata Institute of Fundamental Research (TIFR).

"These results will be valuable to learn more about herd immunity," stated a Brihanmumbai Municipal Corporation (BMC) release.

The BMC also said that it will conduct another survey to identify the spread of the virus and throw light on the herd immunity as well. The civic authorities claimed the sero surveillance result indicates that "asymptomatic infections are likely to be a high proportion of all infections".

"Although prevalence in women was marginally higher than men, the age-wise prevalence in the population was comparable in these wards," the BMC said.

The BMC claimed that higher prevalence in slums could be possibly due to population density and shared common facilities like toilets and water points, the release said. 

The civic body further claimed that although it is still unclear what level of prevalence leads to herd immunity, findings indicate that at least in slums this could be attained sooner than later if the immunity exists and persists in a significant proportion of the population.

The civic body said the sero-surveillance survey also indicates that the infection fatality rate (IFR) is likely to be very low, in the range of 0.05-0.10 per cent. A serological survey involves testing of blood serum of individuals to check for the prevalence of antibodies against infection. 

"Lower prevalence in non-slums could be due to better social distancing and access to better hygiene in addition to interventions by MCGM (BMC) to stem the spread of infection," BMC stated.

The BMC said together with relatively low prevalence in non-slums suggests that social distancing and related precautions such as wearing masks are effective in slowing the infection spread and should continue as a new normal in all sections of the society independent of prevalence.

(With PTI Inputs)

Posted By: Talib Khan