Affecting around 52 crore people, the COVID-19 pandemic has hit every nook and corner of the world, contributing to 1.5 crore excess deaths from January 1, 2020 to December 31, 2021 as per the latest World Health Organization (WHO) estimates.
The pandemic has also left India heavily affected, with times when the per day cases rose to more than 90,000 during the first wave period starting from March 2020. Efforts are carried out throughout the world to mathematically model and fit the available datasets to estimate the excess mortality attributable to COVID-19 owing to the fundamentality of mortality estimates for public health decision making.
The estimate by The Lancet places India at first having the highest number of cumulative excess deaths due to COVID-19 at the level of 41 lakh based on vital registration system data from 12 States.
The estimates by WHO also comes around 47 lakh for the period between January 1, 2020 and December 31, 2021.
Objecting mathematical models
The Indian government, however, has objected to the use of mathematical models in the estimation of excess mortality by the WHO, when authentic data is available in the country. The criticism is based on placing of India among the tier II countries for which mathematical modelling is carried out and the use of unsound statistical methodology.
Though India has argued against WHO by citing the availability of comprehensive civil registration system (CRS) data, sources from within the country are questioning the shortcomings of vital registration and classification of COVID-19.
The advisory nature of the guidelines on classification of COVID deaths by the Indian Council of Medical Research (ICMR) has created confusion among States on what counts as a COVID-19 death and what does not.
In this backdrop, we have tried to provide empirical estimate of the excess mortality attributed to COVID-19 during the period between January 1, 2020 and December 31, 2020 by using information from multiple official data sources. We have used number of registered deaths in the year 2019 and 2020 from CRS, population projections for the years 2016 and 2021 by the Registrar General of India (RGI), crude death rate (CDR) estimates for 2019 from Sample Registration System (SRS).
We estimated the proportion deaths registered in the year 2019 using CRS 2019 and SRS 2019 death data and mid-year population of the year 2019.
Further, we applied the same figures for proportion death registered assuming that it has not changed significantly in the year 2020. The total deaths for the year 2020 are computed for India and larger States using the number of registered CRS 2020 deaths and percentage deaths registered during 2019.
The projected mid-year population for 2020 and the total estimated deaths for the same year are utilised to estimate the CDR for 2020, whereas the CDR of 2019 is taken from SRS 2019. The difference between the CDRs of 2020 and 2019 refers to the rise in the mortality directly or indirectly attributed to the pandemic. Excess death is termed as the difference in estimated number of deaths in 2020 and expected deaths (applying 2019 CDR to the 2020 population) for the same year.
Effects of first COVID wave
As per our estimate, India has witnessed an excess mortality of 0.5 death per thousand population during the first wave of the pandemic (CDR of 6.0 in 2019 to 6.5 in 2020). The highest difference is found in the State of Delhi, where the period saw an excess mortality of 3.8 deaths per thousand population, followed by Tamil Nadu (2.9), Andhra Pradesh (2.3), Karnataka (2.1), and Gujarat (2.0).
The lowest difference in CDR between 2019 and 2020 is found in the States of Telangana (-0.5 i.e. negative change), Uttar Pradesh (0.05 less deaths per 1000 population), followed by Uttarakhand (0.02). Negative change in CDR across these States can be due to the under reporting of deaths as compared to the previous year. Kerala did not report any change in CDR indicating no significant change in mortality as compared to the year 2019.
The States’ tally
Our computations estimate the excess deaths in India during 2020 with respect to 2019 as 7 lakh, with Tamil Nadu (2.2 lakh), Bihar (1.5 lakh), Maharashtra (1.4 lakh), Karnataka (1.4 lakh), Gujarat (1.3 lakh) and Andhra Pradesh (1.2 lakh) having the highest number of excess deaths.
During the same year, India’s official tally of COVID-19 deaths was 1.5 lakh, almost 4.7 times less than our estimate of excess mortality.
The estimated excessive deaths in the period can be attributed to multiple reasons directly or indirectly linked to the pandemic. COVID-19, of course, is the major killer, but not the sole one.
Delayed treatment of serious morbidity conditions has had its share in the excess mortality throughout the world.
Emergency services hit
Studies have shown that the services for tuberculosis, cancer, cardiovascular disease, diabetes, etc. have been disrupted and the mortality associated with it has increased unusually.
According to the Global Tuberculosis Report (WHO, 2021), the largest decrease in the diagnosing and reporting of tuberculosis is observed in the Asian countries, with India in the lead. Additionally, the pandemic has also indirectly affected the maternal and child healthcare by delaying the access to emergency services.
Apart from these, other reasons including long-distance migration, massive poverty, hunger etc., could have also contributed to the excess deaths. Once the CRS 2021 report is released, we will be in a better situation to provide robust and precise estimates of the excess deaths which occurred during the second wave and to conclude to what extent the WHO estimates are correct.
Nandlal Mishra is a PhD scholar at the International Institute for Population Sciences, Mumbai. Devikrishna NB is a post-graduate student at the International Institute for Population Sciences, Mumbai