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Covid third wave ‘inevitable’ in India, say health experts


Health experts have warned that a Covid-19 third wave is “inevitable” in India, as evidence grows that new variants are a contributing factor behind the country’s vicious second wave.

India broke global records again on Thursday, recording 412,784 new cases and 3,980 deaths over 24 hours. Experts believe the real figure to be much higher.

K Vijay Raghavan, principal scientific adviser to the Indian government, said at a briefing on Wednesday that the high levels of the virus circulating in India meant that “a phase 3 is inevitable” but emphasised he could not give a timeline at this stage.

Raghavan admitted that the government had not expected the “ferocity” of the second wave which has enveloped India over the past few weeks, with devastating consequences. According to the WHO, last week India accounted for 46% of the world’s new coronavirus cases.

He said there was a high likelihood of new variants emerging in the India in the future, which might be more “immune evasive” and transmissible, and that even after this second wave had plateaued, strong disease surveillance and Covid-19 safety measures should remain in place in India.

Raghavan’s cautious warnings were a stark contrast to the government’s messaging at the beginning of this year, after India’s first Covid-19 wave had died down, when “victory” was declared over the pandemic in the country.

There is increasing evidence that new variants are contributing to the devastation currently being experienced in India. Analysis of test samples carried out by India’s Sars-CoV-2 Genomics Consortium detected the B1617 variant, known as the Indian variant, in 18 states.

According to early studies, experts and virologists believe the Indian variant may be more transmissible and makes people more susceptible to reinfection but research is still ongoing. WHO has declared it to be a “variant of interest”.

Those states where it has been detected included some of the worst hit regions, including Delhi, Maharashtra, West Bengal, Chhattisgarh and Karnataka.

The Indian B1617 variant appears to be gradually overtaking the UK variant, which has been particularly prevalent in states such as Punjab where it was found to be behind almost 80% of cases.

Sujeet Singh of the National Centre for Disease Control emphasised that while there is growing evidence for the link between Indian variant and the second wave, “its epidemiological and clinical correlation is not fully established”.

“Without the correlation, we cannot establish direct linkage to any surge,” said Singh. “However, we have advised states to strengthen public health response: increase testing, quick isolation, prevent crowds, vaccinations.”

India has been accused of being slow to sequence Covid-19 samples to detect variants, with only about 1% of samples undergoing genome sequencing.

Virologists and Covid modellers have said that variants are likely a significant cause for the surge in the virus in India, which has spread unstoppably in India’s big cities and is now devastating rural communities.

Murad Banaji, a mathematician who has modelled India’s Covid-19 pandemic, said his predictions last year had shown that a second wave was “highly likely” in India once all lockdowns and restrictions were lifted, but according to data, “it should have been relatively muted in urban centres which had already been hit badly – nothing of the scale that we’ve actually seen.”

According to Banaji’s models, the virus has behaved differently this time round, which could probably be explained by new variants which are more transmissible or able to evade prior immunity.

Banaji added: “The reality is that India was always vulnerable to a new surge, whether or not some more transmissible variants emerged, but the scale and the speed of it, especially in some hard hit areas such as Delhi and Mumbai, would be hard to explain if you didn’t have variants at play.”

The WHO said recently that the Indian variant had now been detected in 17 countries. Fears over the spread of the Indian variant have led to multiple countries, including the UK, Australia and Sri Lanka, placing restrictions or outright bans on people flying in from India.



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