BENGALURU: The first round of Mumbai’s serological survey is out, and initial reports indicate that the Covid-19 virus there probably reached its peak. Unfortunately, in Karnataka, though a similar survey was suggested months ago, the state government seems to be sitting on the idea.
“This survey was suggested long ago, and it’s been lying with Health Minister B Sriramulu for the past two weeks for clearance. The technical Covid committee has also cleared the file, but the health minister is taking his own time,” said a senior doctor on the Covid suggestion team.
In Mumbai’s serological survey, researchers found Covid-19 antibodies present in 57% of participants from slums, and 16% of participants from non-slum areas. The survey was a joint effort by NITI-Aayog, the Municipal Corporation of Greater Mumbai and Tata Institute of Fundamental Research, Mumbai.
A sero survey helps identify individuals who were previously infected with the virus and have now recovered, and also indications of whether we are heading towards herd immunity.
Explaining the findings, Dr Giridhara R Babu, senior epidemiologist, said, “Mumbai’s latest findings in slums are among one of the highest exposure rates found globally. However, the other section of the survey shows that about 16% have developed antibodies. A recent Delhi sero survey found 23.48% of the population had developed IgG antibodies and Ahmedabad has shown about 17.6%,” he said.
Most Indian metros which did the survey got results in the 17%-23% range, which reflects the background in terms of the proportion of people who have developed antibodies. “We still have about 80% of people susceptible to Covid. This needs to be understood and complacency shouldn’t set in,” he explained.
Interestingly, Mumbai, Ahmedabad and Delhi have already done with the sero survey, while the southern states are yet to take a decision on it.
A senior virologist from Manipal explained that the survey in Mumbai has shown a few interesting findings. “It shows that transmission pattern varies from region to region, especially from slum to a high-rise, and more such surveys will be needed to assess a pattern. Slums are very densely populated and some of our metros too have such regions, which are already proven to be infection clusters,” he said.
A similar study in Karnataka’s main metros could also map the transmission pattern.