Q/ Should we be worried about the Delta Plus variant?
A/ It has just been over a month since this variant was identified. It is a variant of an already known mutation, with one more mutation (also seen in the Beta and Gamma variants) on top of the existing mutations in the Delta variant. There have been very few cases so far.
A new variant is characterised in two ways. One, by genetic sequencing, which is very quick these days and therefore we know the genetic structure of this new variant. The other way to characterise it is through its clinical and epidemiological manifestations. We have to see how this variant behaves over a period of time to understand this aspect.
Q/ But it is being called a variant of concern (VoC).
A/ There are at present four VoC—Alpha, Beta, Gamma and Delta. Delta is already established as more transmissible. We consider all its sub-lineages also as VoC, and Delta Plus already has the traits of Delta. But, whether it even more transmissible and virulent than Delta, will need more time to establish.
Q/ The arrival of Delta Plus has stoked fears that the third wave is round the corner.
A/ Every new variant does not usher in a wave of infection. I understand there should be a scientific zeal in identifying new variants, but our discussions should be in identifying transmission and virulence, which is why ICMR, along with the Imperial College of London, did a modelling exercise to predict the “third wave”.
We factored in four scenarios: the waning of acquired immunity from previous infections and even vaccination; the appearance of a new variant that escapes natural and acquired immunity; the rise of a variant that spreads faster; and the lifting of state-level restrictions on the public.
The model shows that in any situation, the third wave will not be as severe as the second wave. And if we top at least 40 per cent vaccine coverage within three months of the second wave, we can actually reduce the peak of the third wave significantly.
So remember, even if we get a more transmissible new variant, it does not automatically mean a higher peak than the previous wave.
Q/ What should we be worrying about?
A/ Eighty per cent of infections in the second wave were restricted to ten states. Many states, looking at the experience of Delhi and Maharashtra, imposed strict curbs early on and, therefore, escaped the ravage of the wave. This, however, means that their populations are vulnerable to the infection. They need to be extremely cautious with lifting curbs. Without a robust vaccination ramp up, a sudden reopening could lead to big problems there. Remember, we are not in the hands of fate. We understand biology, transmission and virulence, and we can control the next wave.