Can’t use sero-surveys to claim under-reporting, says government

NEW DELHI: National sero-surveys cannot be extrapolated to conclude the actual number of infections were under-reported, the government said pointing out that over 80% of infections are asymptomatic and not reported but are detected during sero-surveys.
The latest sero-survey also included vaccinated individuals who are likely to have got vaccine generated antibodies, the Centre said, and also highlighted that national level sero-surveys are not meant to reflect the granularity at the level of states. The point was underlined in the context of “over reading” of state-level projections. It was felt that for states, it was better to refer to sero surveys conducted by the regional governments rather than the national survey.
“Making a mathematical calculation and drawing a picture of your own is not scientifically valid. This is not a way of data interpretation,” Niti Aayog member Dr V K Paul said. Findings of the fourth national sero survey shows 67.6% of the general population had antibodies against the SARS-CoV2 virus.
“Sero-survey is carried out with the specific purpose of enunciating how many people have previous experience of Covid… It is not meant to cover the granularity at the level of state(s)… This isn’t the way interpretation of data should be done or convey misleading info,” Paul said. The comment came in the wake of reports that sero-survey findings show a serious under-counting of actual infections.
“All the sero-surveys that have been done portray the national picture. If the antibody is found in any person it shows the person has been exposed to Covid. It doesn’t mean it was a serious disease,” Paul said. Officials also said it would be difficult to make a count of asymptomatic persons in any country and surveys throw up estimates. He also said while most cases are asymptomatic, it’s possible that such people don’t get tested, and may not be aware about the incidence of the disease. But, in sero-surveys such asymptomatic cases may also get reported.