6.4 million Covid-19 cases were estimated in India by early May, says first national serosurvey report

The survey was conducted from May 11 to June 4 on 28,000 people and estimated 64,68,388 adult Covid-19 infection in India by early May.

An estimated 6.4 million or over 64 lakh cases of Covid-19 were estimated in India by early May, the much-awaited findings of the country’s first national serosurvey conducted by the Indian Council of Medical Research (ICMR) in the Indian Journal of Medical Research, said.

People wait their turn to give samples for coronavirus testing, at Sector 30 District Hospital, in Noida on Thursday, September 10, 2020.(Sunil Ghosh/Hindustan Times)

The survey report said 0.73% or 64,68,388 adults were exposed to SARS-CoV-2, the virus which causes the coronavirus disease.

The national serosurvey was conducted from May 11 to June 4 on 28,000 people, whose blood samples were tested for IgG antibodies using Covid Kavach ELISA kit.

Also, seropositivity was found to be the highest in the 18-45 age group (43.3%), followed by the 46-60 age group (39.5%). It was found the lowest among those aged over 60 (17.2%).

“The findings of our survey indicated that the overall seroprevalence in India was low , with less than 1% of the adult population exposed to SARS-CoV-2 by mid-May 2020,” the survey report said.

“The low prevalence observed in most districts indicates that India is in early phase of the epidemic and the majority of the Indian population is still susceptible to SARS-CoV-2 infection,” the report further stressed.

Based on the overall seroprevalence of 0.73% and the reported number of Covid-19 cases, it was estimated that for every RT-PCR confirmed case of Covid-19, there were 82-130 infections in India.

As part of the survey, a total of 30,283 households were visited from 700 clusters in 70 districts. The stratification of the districts as zero cases (15 districts), low (22), medium (16) and high (17) was done on the basis of the reported number of Covid-19 cases as on April 25.

India is the currently the second worst-hit country after the United States with a total of 44,65,863 Covid-19 cases thus far.

(With PTI inputs)