JOIN USCoronavirus: ICMR set to start third serosurvey in Dec-Jan
Indian Council of Medical Research (ICMR) is set to start its third sero-surveillance across the nation in December-January to find out the prevalence of the Covid-19 epidemic, a year after the disease struck the world’s second-most populous nation.
"The third serosurvey would be undertaken between December and the first week of January. It will include the same 70 districts that were covered in the first two rounds,” Samiran Panda, who heads ICMR’s epidemiology and communicable disease division told DH.
Conducted between August 17 and September 22, the second survey showed 7.1% prevalence among the adults – a ten-fold rise from the first survey. Since kids were omitted in the first round, ICMR included individuals aged 10 years and above in the second survey and found that with their inclusion, the prevalence was 6.6%.
The second survey period was followed by Durga Puja-Dussehra-Diwali-Chhath festivities and Bihar assembly polls that witnessed widespread mingling of people and crowding of the public space caring little for the Covid-19 appropriate norms.
With no sign of a second surge yet in most of the states, experts fear that the prevalence must have increased manifold in the past three months exposing a large number of people to the virus even though they didn’t have any symptoms. This may have shrunk the pool of susceptible people.
“The approximately 7% prevalence indicated in the second ICMR serosurvey is likely closer to 20% by now. The epidemic can be expected to have largely exhausted itself in the major cities with the bulk of new cases expected to be from the rural districts,” said Gautam Menon, a professor at Ashoka University. "A large increase (in prevalence) is very much possible," corroborated Gagandeep Kang, a senior scientist at CMC Vellore.
Results of the third survey is likely to come out before the Centre launches the Covid-19 vaccination programme in which the government plans to vaccinate 30 crore Indians with the objective aim of breaking the virus’s chain of transmission.
Three crore healthcare and front-line workers will get the shot in the initial rounds followed by another 27 crore senior citizens with co-morbidity.
A section of scientists, however, observed that such sero-surveys were not much of use as they failed to capture the local variations.
“Since the epidemic consists of large numbers of local outbreaks, the proportions of people exposed would also vary greatly by locality. There is so much variation in locations of outbreaks and rates of spread that the kind of sero-surveys ICMR has done are nowhere near adequate to tell us anything meaningful about these local variations,” commented Satyajith Rath, a visiting faculty at the Indian Institute of Science, Education and Research, Pune.