‘What is driving the second wave of COVID-19’ has been a question that scientists and public health experts are trying to figure out — is it because the public is not strictly following COVID-19 appropriate behaviour (wearing masks and maintaining safe distance), or due to the new variants of the COVID-19 virus or a combination of both? On the other hand, experts are trying to find the answer to another question — When will the second wave of COVID-19 peak and/or wane?
Numerous data science experts and institutions have predicted the trajectory of the pandemic using various models and parameters, including the number of reported and unreported infections per day and the number of people who have been exposed to the virus, among other parameters (example, the number of people getting vaccinated). Accordingly, experts have estimated that the second wave of COVID-19, or the massive surge in the number of infections, is likely to see a sharp increase from mid-April until May 2021. It is likely to decline from June, many have predicted.
However, previous projections and estimates by the Indian government-appointed committee failed to predict a second wave. The earlier projections estimated that the pandemic would decline by February 2021. They however had warned that the downward trend will continue only if COVID-19 appropriate behaviour such as masking, disinfecting, tracing and quarantine are practised. With the economy opening up, rampant election campaigns and COVID-19 vaccination drives since the beginning of 2021, many safe practices were ignored. In July 2020, a study by the Massachusetts Institute of Technology (MIT) had warned that India's COVID-19 cases are likely to surge up to 2.87 lakh by early 2021, if a treatment or vaccine is not developed soon. Here is a look at what different experts have predicted this year.
Indian Institute of Science (IISc), Bengaluru: According to the projections by professors Sashikumaar Ganesan and Deepak Subramani, and research student Thivin Anandh, from the Department of Computational and Data Sciences (CDS), April 20 and June 10 are predicted to see a sharp increase in active COVID-19 cases — 6 lakh (673.14k) and 2 lakh (288.88k) respectively. In May, it will see a marginal dip, followed by a surge in June and then a minor dip.
Second wave peak prediction by IISc Bangalore
“By May 2021, 1.36 crore people in India will get infected, and by September 1, 1.53 crore individuals will get infected. The second wave peak will be around the mid of April with a maximum active cases of 7.3 lakh,” the team said. In states such as Karnataka and Tamil Nadu, the maximum active cases during the peak will be 36,000 and 27,000 respectively.
The IISc team made the COVID-19 wave two projections with three assumptions — the infection spread is similar to March 23 and October 1, 2020; About 30 lakh people are getting vaccinated daily and the vaccine efficacy is 70%; and 20 times the prevalence factor based on serosurveys to find how many individuals in a given population have been exposed to the virus.
Indian Institute of Technology (IIT) Kanpur: Professor Manindra Agrawal, head of the Department of Computer Science and Engineering at IIT Kanpur, used the mathematical model applied last year (which predicted the cases will subside in February 2021) this year too. Accordingly, the scientist and his team, too, has predicted the coronavirus cases are likely to spike in mid-April, sometime between April 15 and 20, although there may be variations in the number of cases. For the last few days, India has been reporting a record-high of more than two lakh cases daily. The cases are likely to come down fast and there may be a dramatic reduction by the end of May.
Gautam Menon, Ashoka University, Haryana: Gautam Menon, professor of Physics and Biology at Ashoka University who carried out independent calculations, also projected that the second wave will last between mid of April and May. He also pointed out that the number of daily infections has gone up by 50% in March in India. The professor traced the course of the pandemic using three parameters — ‘Beta’ or the number of daily infections; ‘Reach’ or the level of exposure of the population to the virus; and ‘Epsilon” or the ratio of detected and undetected cases.
COV-IND-19 Study Group: This interdisciplinary team of data scientists and scholars, led by Bhramar Mukherjee (a professor at the Michigan School of Public Health) has projected that India is likely to see a peak in the second wave in May. By May 17, India is projected to record 3.30 crore (3,30,36,652) COVID-19 cases. As per the short-term forecast, there will over 3.15 crore cases between April 19 and May 17. This is the predicted cumulative short-term case counts under the assumption that there is no intervention such as physical distancing and lockdown.
Short-term forecast by COV-IND-19 Study Group
Virologists, retired professors of Christian Medical College, Vellore: India is 56 days into the second wave of COVID-19, read an article in The Hindu, jointly authored by two eminent virologists — Dr T Jacob John, a retired professor of Clinical Virologist at CMC Vellore; and MS Seshadari, retired professor of Medicine and Endocrinology, CMC Vellore, and currently the Medical Director of Thirumalai Mission Hospital in Ranipet, Tamil Nadu. According to these experts, if the peak is likely to happen within the next four days, it would have taken the country 60 days to reach from base to peak. The descent after this peak will take an equal amount of time, that is, two months (in the normal bell-shaped epidemic curve). While 29,66,583 COVID-19 cases have already been detected by April 13, the experts have predicted the cases to reach 3.1 million. Considering the slow pace of the vaccination drive, the experts said that vaccination may not decelerate the second wave but it may reduce mortality among those elderly and vulnerable citizens who have received the vaccine.