The third Covid wave will be a “ripple” in case there is no significantly faster-spreading mutant. However, if there is a faster-spreading mutant, the magnitude of the third wave will be “comparable to the first one”, according to projections of the Government-backed ‘Sutra’ model for Covid-19.
Maninder Agarwal, Professor, IIT-Kanpur, who was part of the team of scientists behind the Sutra analysis said that they have created three scenarios.
“The optimistic one — where we assume that life goes back to normal by August, and there is no new mutant. Second the intermediate one — where we assume that vaccination is 20 per cent less effective in addition to optimistic scenario assumptions. Third pessimistic one —this has an assumption different from the intermediate one: a new 25 per cent more infectious mutant spread in August,” he added.
As per the Sutra model, if there is an immunity escape mutant, all the above scenarios will be invalid. The IIT-Kanpur professor further said, “First, loss of immunity in the recovered population, second vaccination-induced immunity. Each of these two needs to be estimated for the future. And third, how to incorporate the two in the model.”
In yet another study by IIT Kanpur, the researchers showed that the third wave of Covid-19 is expected by September to October this year.
The study was done by Professor Rajesh Ranjan and Mahendra Verma, along with their team.
It said, “There is significant anxiety among policy makers and the public about the third wave. For the same, using the SIR model, we have constructed the following three scenarios of a possible third wave using the epidemic parameters of the second wave. We assume that India is fully unlocked on 15 July.”
He said under the Scenario 1 third wave will peak in October but a lower peak height than the second wave while in the scenario 2 (Normal with virus mutations), the peak could be higher than the second one and may appear early (September). “ In scenario 3 with stricter interventions, the peak of the third wave could be delayed until late October with strict social distancing. Here, the peak will be lower than the second wave.”