Home / India News / 57% Mumbai slums residents found Covid-19 positive, experts divided on herd immunity
As Mumbai’s civic body, the Brihanmumbai Municipal Corporation, gets ready to conduct the second round of serological survey, experts are divided over whether the residents of the city’s slums are approaching herd immunity for coronavirus disease, Covid-19.
In the first sero survey conducted in July, the BMC found 57% infection prevalence in slums. In the second survey, authorities will check if the presence of antibodies has declined or increased in the same set of people that were part of the first survey.
According to experts, the march of an infectious disease such as Covid-19 can be halted only when there is a large enough proportion of the population that is immune to it – a threshold known as herd immunity. Besides a vaccine, the only way people become immune is if they have had the disease and recovered.
Jayaprakash Muliyil, chairman of the Scientific Advisory Committee of National Institute of Epidemiology, believes that Mumbai’s slums may have acquired herd immunity.
“Mumbai’s slums may have reached herd immunity,” said Muliyil according to a Bloomberg report quoted in a CNN article. “If people in Mumbai want a safe place to avoid infection, they should probably go there.”
However, some other scientists are more cautious. The CNN article quoted David Dowdy, an associate professor in epidemiology at Johns Hopkins Bloomberg School of Public Health, as saying it was possible that the researchers had used a test that created false positives.
The article also quoted Om Shrivastav, a Mumbai-based infectious diseases expert, as saying that with less than eight months into the virus’ existence in society, it was too early to make any “decisive and conclusive statements”
India’s health ministry has also said that herd immunity is “far away” for the Indian population.
“In a country with the size of the population like India, herd immunity cannot be a strategic choice or option. It can only be an outcome, and that too at a very high cost as it means lakhs of people would have to be infected, get hospitalised and many would die in the process,” Rajesh Bhushan, the officer on special duty, health ministry, said last month.
David Dowdy, too, says that millions of people will die in the process of developing herd immunity in a population.
“We could very rapidly develop a population immunity to the coronavirus simply by exposing every single person in the population to the disease ... it’s just that millions and millions of people are going to die in the process,” Dowdy was quoted as saying in the CNN article.
Meanwhile, Mumbai recorded 1,132 new infections, taking the city’s tally to 126,356. Mumbai also recorded 50 new fatalities, pushing the toll to 6,943, while also crossing the 1 lakh mark in recoveries on Wednesday. Now, the city has 19,047 active cases.
India saw its Covid-19 tally jump by 66,999 new cases - highest single-day spike - on Thursday which pushed the number of cases to nearly 2.4 million.
The country recorded 942 fresh fatalities in the last 24 hours, which pushed the death toll due to the disease to 47,033.