The findings of the first national population-based sero-survey conducted by the Indian Council of Medical Research’s (ICMR) has raised several questions about the Coronavirus data reporting in India. At a time when India is reporting nearly one lakh cases daily, ICMR’s sero-survey result – which is three months delayed – has raised more questions than offering help in mitigating the pandemic.
The national sero-prevalence survey, published in the Indian Journal of Medical Research on September 10, 2020, repeats what ICMR officials said on their June 11 press briefing. It states that 0.73% of adults in India were exposed to the novel coronavirus, translating to 64 lakh infections by early May. This is in stark contrast to India’s cumulative caseload on May 7 which stood at 52,592.
The delayed survey result also reveals that the Ministry of Health & Family Welfare (MoHFW) reported nearly 10,000 less Covid-19 cases than recorded in ICMR database on at least two occasions in early May. Experts are raising concerns over such discrepancy in data reporting, as it could have affected several decisions which have been taken on the basis of these data.
“We used the ICMR database for the reported number of cases every day. All labs submit their data to the ICMR database,” Dr Manoj V. Murhekar, lead author of ICMR paper on sero-survey told India Today.
Written by over 70 experts, ICMR paper reported that on May 11 and May 3, 2020, a “total of 79,230 and 49,720 Covid-19 cases reported in India by the respective dates” (page number 06). However, the health ministry reported 67,152 and 40,263 number of cases, respectively, on the given dates, an average of 10,000 fewer cases than recorded by ICMR.
The discrepancy in Covid-19 data
The health ministry’s website has reported almost 9,000 and 12,000 fewer cases than ICMR on May 3 and May 11, respectively. This shows that gap in reporting of numbers gradually increased as well.
Experts said this is a huge gap between ICMR and health ministry’s numbers. It raises doubt about data reporting of Covid-19.
“10,000 is a huge difference if you see the number of total Corona cases at that time, which was less than one lakh. No one knows but this difference might exist even today with a wider gap. The government should clarify such discrepancy,” Dr Vikas Bajpai of Centre of Social Medicine and Community Health, Jawaharlal Nehru University, said to India Today.
Some experts said that discrepancy might have occurred because the case numbers were growing fast during that time and on an average, it took 2-3 days to reach the health ministry’s dashboard.
“The time lag in MoHFW numbers shows there were some inefficiencies and delays in gathering and collating data. It is an issue if there wasn’t one reliable source of information on nationwide cases and deaths,” Dr Murad Banaji, a mathematician at Middlesex University London, said to India Today.
The health ministry website mentions in its footnote of state data tab that “Our figures are being reconciled with ICMR”, but the website is devoid of any historical data with updated figures. To verify the reconciled data of the given dates, India Today’s Data Intelligence Unit (DIU) checked the World Health Organization’s (WHO) Covid-19 dashboard. We found that the reported cases from India were listed as 39,980 and 67,152 on May 3 and May 11, respectively.
While the data of May 11 matches that of the health ministry’s, the cases listed on May 3 were even lesser than what the ministry recorded. Both the data were still less than what ICMR recorded on the same day.
According to the health ministry, any data discrepancy at all will be addressed by them, the ICMR and the states together. Rajesh Bhushan, Secretary, Ministry of Health and Family Welfare said, “Whenever you maintain large databases that are fed on a real-time basis, by about 30 states and other union territories, and on a daily basis, data discrepancies do happen but these are addressed on a daily basis as it is a dynamic ongoing process. The ICMR, the ministry’s team as well as teams of the states and UTs together address this.”
Why data discrepancy matters
DIU noticed this difference in Covid data during the analysis of ICMR’s sero-survey research paper. We found that ICMR has mentioned nearly 10,000 more cases in the calculation of infection to case ratio. ICMR reported the infection to case ratio as 130.1 and 81.6 for May 3 and May 11, respectively.
In simple words, the infection to case ratio implies that for every one RT-PCR confirmed case of Covid-19, there were 82-130 other infected people in India that we missed during the survey period.
Dr Banaji explained that case infection ratio will change with the change in reported cases for a given date. “Using MoHFW numbers, the infection case ratio for May 3 would go up from 130 to 160. The ratio for May 11 would go up from 82 to 96. But I suppose the ICMR numbers are the “correct” ones. There are many uncertainties in estimating the infection case ratio. The biggest uncertainty is in the total infections – the 95% confidence interval is 3.82 million to 11.1 million, which is very wide. The best we can say is that the infection case ratio was high: only around 1% of infections had been detected at that point,” Dr Murad further explained.
ICMR, though, agreed that even if there would be a change in the given numbers of reported cases, seroprevalence will not change. “Overall conclusions (that the SARS-CoV-2 spread was low at the beginning of May 2020), as well as seroprevalence, won’t change. However, with a lower number of RT PCR + cases reported by the health ministry, the infection to case ratio would be higher than we calculated,” Dr Manoj explained to India Today.
In the time of the pandemic, data transparency is crucial to come up with feasible mitigation strategies. From tracing to isolation and other policy steps depend on the mapping of the prevalence of the cases. The discrepancy in data not only weakens the belief in the government agencies but also raises doubts over the findings of the research based on them.