India is experiencing a third wave of COVID 19 with daily cases in the country back in the range of 1 -- 1.5 lakh. There are a surge in infections in metro cities like Delhi and Mumbai, with cases doubling in 2 -- 3 days time. The big question is when will India and the metro cities reach the peak of this third wave?
According to M Vidyasagar, head of the National Covid 19 Supermodel Committee, cities like Delhi and Mumbai will peak in the next 7 -- 10 days, while India may reach the bottom of the curve by the end of February.
Vidyasagar said that case count is a wrong parameter to measure the severity of the third wave.
Since this virus is just a week old in India, the consequences of this is that we can predict the timing of the peak with reasonable certainty but not the height of the peak. I think cities like Mumbai and Delhi, where cases are rising, will peak in next 7 -- 10 days and then cases will start to come down very sharply. He said that the number of cases can't be predicted now.
According to Vidyasagar, a professor at the Indian Institute of Technology IIT in Hyderabad, policy making is wrong on the basis of number of cases.
If we have 8 lakh cases a day but the hospitalisation rate is still 3 -- 3.5 per cent, the number of hopitalisations will be around 28,000, and we know that the average stay in the hospital has come down from 10 days to 5 days, so multiplying 28,000 into 5 days will have around 1.4 lakh people hospitalised at any given time. The total burden on hospitals would be around 1.4 lakh, this is less than what we had in the second wave, he said.
He said that the hospitalisation rate and oxygen requirement should drive policy making in the country. If 25 per cent of hospital beds are occupied, we should do something, and when 50 per cent of hospital beds are occupied, we should take some more measures. These are the modifications we need to make to decide when we take various steps, according to Vidyasagar.
Vidyasagar co-authored the government-backed SUTRA Susceptible, Undetected, Tested Positive and Removed Approach Model, a mathematical model for pandemics, along with Manindra Agrawal of IIT Kanpur and Lt Gen Madhuri Kanitkar of the Integrated Defense Staff.
Vidyasagar described the methodology of the model, saying that it estimates three quantities - how fast the virus spreads, the extent to which a variant bypasses vaccine protection, and the extent to which it bypasses natural immunity.
The number could be 30 per cent, 50 per cent, etc. when estimating the extent to which the virus bypasses the natural immunity is full of uncertainty. He said that we don't have enough data to estimate this number because this variant is a week old in India.
He predicted that each city would have a very sharp curve, though timing would be different. When all these are added together, the overall India curve will look more flat.
As we know, the first wave took 20 weeks to peak, began around March, peaked in mid September and then began coming down, the second wave took around 8 -- 10 weeks to peak, this time nationwide it might take 5 -- 6 weeks to peak, he said.