However, the higher number of infections -- 40,953 on Friday taking the total tally to 1,15,55, 284 on Saturday -- has not led to a higher case fatality rate, which continues to remain below 1.5 per cent.
Experts say nothing conclusive can be said on low case fatality rate, as it is a complex issue. There are also mixed views on the probability that a lot of the younger population is being infected, which does not have high mortality due to viral infection. However, experts' opinions converge on better hospital care management, taking into account nearly a year with the virus, which helps in saving lives. Case fatality rate denotes deaths over total number of cases.
On November 28, last year, a single-day spike of 41,810 new infections was recorded. For the 10th consecutive day, in March, the country has been registering a rapid increase in cases. According to the Health Ministry, Maharashtra, Punjab, Karnataka, Gujarat and Chhattisgarh are registering a steep rise in daily numbers. Raman Gangakhedkar, former head scientist of the Epidemiology and Communicable Diseases Division at the Indian Council of Medical Research (ICMR), said there is a possibility that the younger population is being exposed to new surge in viral infection -- as lockdown does not exist anymore and there is more mobility of younger people -- and they have low fatality rate, and also the older population is preferring to stay indoors. "It seems that the new surge in cases is not because of new variants. Perhaps due to the age group of people being infected, the fatality rate is low. This cannot be ruled out", added Gangakhedkar.
Although, the fatality rate is low, yet health authorities are concerned with the increase in number of deaths since the beginning of March, where more than 100 deaths were reported daily for many days.
Rajni Kant Srivastava, Director, ICMR-Regional Medical Research Centre (RMRC), Gorakhpur and head, Division of Research Management, Policy, Planning and Coordination (RMPPC) at ICMR, said the case fatality rate is down due to ongoing vaccination drive and if no dose of vaccine is administered, the people infected with virus has low chances of developing complications. "There is a possibility that the younger population is getting more infected amid the surge in infections. Therefore, they have low chances of developing complexities. Vaccination will reduce fatality", added Srivastava. On the possibility of the UK and Brazil variant of the virus being a possibility behind the recent surge in cases, he added that it is difficult to say these variants are responsible, as scientifically their role has not been established so far.
The coronavirus, which caused the deadly pandemic, like all viruses keeps changing in small ways and the vast majority of these mutations are inconsequential. These mutations also do not change the way the virus behaves.
Rakesh Mishra, Director at the Council of Scientific and Industrial Research-Centre for Cellular and Molecular Biology (CSIR-CCMB), Hyderabad, said there is no data to show decline in mortality due to increase of infection in the younger population amid the ongoing spike in daily cases.
"Major improvement has been made in taking care of coronavirus patients in the hospital. People are given proper drugs. Earlier there was a panic due to coronavirus," said Mishra. He further added that some variants going around in many places seemed to be less symptomatic and leading to less mortality, and now there is better understanding of the disease in the system.
According to the health ministry data till March 17 shows average daily new cases are increasing over 40 percent week-on-week. Also, week-on-week, new deaths are increasing over 35 percent.
On March 20, the seven-day average of daily new cases is over 30,000 and the seven-day average of deaths is 159. On February 15, the case fatality rate was 1.43 per cent, and since February 21, the new cases started increasing consistently. However, the case fatality rate declined to 1.38 per cent on March 20.
Y.K. Gupta, the President of AIIMS Bhopal and Jammu, said there is nothing conclusive on the cause of decline in mortality, and cited few factors which may contribute towards it. "Some people possibly have immunity (presence of antibodies due to exposure to virus in the past). Secondly, maybe the virulence of the virus is reduced, but there is no scientific evidence to back it so far. Thirdly, our hospital care management has improved, due to the experience gained in the past several months," Gupta added.