India may have 20 times more Covid-19 cases, 4.5 times more deaths than official figures: Study

The study estimated 492 million Covid-19 positive patients in India by May 15 when the official surveillance system recorded only 24.7 million such cases

Amid debate on India’s Covid-19 mortality, scientists on Saturday claimed that by May 15 India might have harboured 20 times more Covid patients and 4.5 times more Covid deaths than what have been captured in the official surveillance system.

They estimated 492 million Covid positive patients in India by May 15 when the official surveillance system recorded only 24.7 million such cases. This means nearly 36 per cent of India’s population has been exposed to the virus since the beginning of the epidemic last year.

Also, as of May 15, India reported 2,69,700 Covid deaths while the researchers calculated that the actual mortality could be around 1.21 million, implying that roughly only two out of every nine deaths have been registered in the official reporting system.

Read | Data proves calling Kumbh a Covid-19 super-spreader unfair: Mela security in-charge

The study, carried out by scientists at the University of Michigan along with scholars from the Indian Statistical Institute, Kolkata and Johns Hopkins Bloomberg School of Public Health, used a sophisticated epidemiological model and publicly available data released by the Indian Council of Medical Research to flag the possibility of under-reporting in India.

The researchers observed that since the findings were based on a computer model, several assumptions were made. “We need updated sero-survey data to check our estimate as models make assumptions that may not hold,” said Bhramar Mukherjee, a professor of epidemiology and biostatistics at the University of Michigan.

“Let us come to fatality rates. We have to recognise that the second wave estimate will change substantially as we do not have complete mortality information. We need reliable mortality data to check our estimate,” she said.

The study – which is not yet peer reviewed paper and published as a pre-print – comes at a time when there are reports on the possible under-reporting of Covid mortality in India with experts raising doubts at official statistics. According to the Union Health Ministry, Covid-19 killed 3,22,512 persons in India till Friday.