With a total of nearly 145,000 confirmed cases and over 4,100 deaths due to Covid-19 reported in India in the past three months, the case fatality rate (CFR) is relatively low as compared to the rest of the 11 worst affected countries, which reported more than 100,000 confirmed cases as of 25 May. Though India showed a surge in new cases during the past few days, the average CFR is relatively low at 2.9%, or one death per every 35 confirmed cases; this is less than half of the global average CFR based on 215 countries, at 6.3%, whereas the CFR for France, Italy, the UK, and Spain ranges from 11.4–15.5%, or one death per every 6 to 9 confirmed cases, followed by Brazil at 6.2%, the US at 5.9%, and Iran at 5.4%. Russia showed the lowest CFR of 1.0% of the 12 worst-affected countries. Germany, considered the model for containment of Covid-19 deaths, has a CFR considerably higher than that of India, at 4.6%.
The surge in cases in India can be attributed to the recent easing of the lockdown combined with an increase in the testing capacity. Due to the ease in lockdown and a significant increase in testing, India is expected to see a peak in cases sometime in June or July. However, the success story for any country relies on how good it is at controlling the deaths from the pandemic, and India has proved to be successful in doing so.
The low mortality rate in India can be attributed to its youthful population structure, the hot temperature, and a milder strain of the virus. Additionally, the early, stringent, and prolonged lockdown helped in averting the expected exponential growth in the new cases and deaths. A recent estimate by the Public Health Foundation of India stated that 78,000 deaths due to Covid-19 have been averted due to the effective implementation of mitigation measures by the government of India. Covid-19 is a highly contagious disease and thus it is not surprising to see a surge in the number of cases, but what could be of concern is controlling the deaths from the virus.
So far, India has tested more than 3.0 million of its population, and the proportion of confirmed cases among the tested population stands at 4.8%, which may translate to an estimated 66.0 million Covid-19 cases currently present in India, assuming that the testing is being carried out on random samples of the population. The real extent of the spread of the pandemic can only be studied through widespread testing of the population. Apart from continuing to use the gold-standard reverse transcriptase, polymerase chain reaction (RT-PCR) test, antibody blood tests are also a good measure to study the population immunity towards the virus, and will also help us to know the number of people who are infected and/or recovered from the virus in the population. If results of the antibody tests are made available, it is possible that approximately 6.0–8.0% of the Indian population might be already infected and recovered from the pandemic. Antibody tests conducted in small samples of the US population have shown that 10–20% of the population samples tested were positive for antibodies; however, these studies have been too small to make any solid conclusion. Additionally, in India and the rest of the world, many people who get infected by the virus are either asymptomatic or with mild infection. Therefore, as the testing capacity increases, more and more cases can be identified in the early stages and therefore better care can be provided to patients, which can further reduce the CFR.
The CFR in this analysis is based on the reported deaths by each country. It is possible that there can be variations in defining the deaths from Covid-19 as there is currently no international standard. For example, if a person dies from a heart attack while recovering from Covid-19, is this person counted in Covid-19 deaths or heart attack deaths? Therefore, once the excess mortality data becomes available for each country, a more accurate CFR estimate can be done in the coming months.