Third Covid-19 wave in India: What experts say about the gap between two waves

The gap between the two waves of the Covid-19 pandemic is not uniform across the world. Germany, France witnessed the third wave of the pandemic in April, while the United Kingdom is beginning to enter the 3rd wave.

Warning about a possible third wave, several experts have predicted the timing of a possible third wave of the pandemic in the last few days. There are mathematical methods to predict this timing and most experts, including AIIMS director Dr Randeep Guleria, opined that the third wave of the Covid-19 pandemic is inevitable in India.

Covid-19 third wave in India will come quickly if social distancing norms are thrown to the winds, experts have said. (PTI)

What is the general gap between the two waves?

A gap of roughly four to five months has been observed between two waves of the Covid-19 pandemic. If India's graph is considered, the first peak was in September and the second peak took place in April-May —in a gap of six months.

A poll conducted by Reuters predicted that the third wave may hit India in October, November — which also is six months away.

AIIMS director Randeep Guleria on Saturday said the third wave may come within six to eight weeks if Covid appropriate behaviour is not maintained properly. According to him, the virus can make a comeback within two months, earlier than the trend noticed in India so far, if the unlocking process is not measured.

Why the gap between two waves is not uniform

Across the world, the gap between the two waves of the pandemic is not uniform as it depends on vaccine coverage, human behaviour, and the variant of the virus. Maharashtra Covid task force member Dr Rahul Padita has said that some countries witnessed a gap of 14 to 15 weeks, but some encountered a fresh wave even before two months of the earlier wave.

For example, Germany, France witnessed the third wave of the pandemic in April, while the United Kingdom is beginning to enter the 3rd wave.

What happened during the 1918 Spanish Flu?

There were three waves in the 1918 Spanish Flu, which had taken place during Spring, Fall and Winter. The second wave was the biggest recording the highest number of deaths.

Swine Flu occurred in two waves between 2009 and 2010.

Why all these outbreaks have waves

The respiratory infections come in waves, Dr Guleria had said earlier. In a press meet earlier this month, Dr Guleria said that waves occur in respiratory disease pandemic because the virus changes its form and a portion of the population remains susceptible to it. But when most people develop immunity — either through vaccination or naturally — the virus becomes endemic. "This is what happened to H1N1. Now the infection has a seasonality. It comes only in monsoon and winter," Dr Guleria had said.