With people dying on the streets and hospitals running out of oxygen, India’s situation is one of the worst the world has yet seen.
But why has India been hit now and might other countries follow?
The first wave
India initially seemed like it might make it through the pandemic relatively unscathed, with a strict lockdown from March 25 to May 31 saving it from the first wave of the virus last spring.
After the lockdown was lifted, the country was hit by a wave of infections but hospitals were not overwhelmed.
So why has India been hit so hard now?
“We let our guard down,” Dr Shahid Jameel, one of India’s leading virologists, said. “It was complacency.”
The government was in a bind: the first lockdown stopped the virus but caused economic collapse and untold human suffering. Spooked, the state is now relying on local authorities to take action.
Critics accuse the government of abdicating responsibility.
In early March this year, health minister Harsh Vardhan claimed India was in the “endgame” of the pandemic. Cricket matches, and massive religious festivals, all largely maskless, were held.
“These were all possible super-spreader events,” said Dr Jameel, of Ashoka University.
Populist Prime Minister Narendra Modi is now being dubbed #superspreaderModi on Twitter and anger is growing across the country.
That is a far cry from March, when Mr Modi was praised as a “vaccine guru”.
India is known as the “world’s pharmacy” for its vaccine production capacity. But getting jabs into people’s arms domestically has proved more challenging.
In some ways, the country has done well, with 139 million doses administered, more than any other country except the US and China. It is also second in the world, behind the US, in terms of second doses administered.
But these figures still only represent around 10 and 1.6 per cent of the vast population respectively: not enough to stop the second wave.
Alongside vaccines, experts say the authorities should have prepared the underfunded healthcare system for the new surge of the virus, lining up supplies like oxygen and planning how to get them to hospitals.
“We celebrated too early,” says Dr Jameel. “Modellers were predicting a second wave. Historically, if you look at respiratory pandemics, they come back.”
But he added: “But nobody really expected it to be this big. We were really caught by surprise and it has completely overwhelmed the system.”
India is not alone in this: British doctors said at the weekend that most people don’t realise how close this country came to a similar collapse when our more transmissible variant, B1117, hit before Christmas.
Dr Julian Tang, respiratory sciences honorary associate professor at the University of Leicester, said the rate of the rise in the numbers of Covid-19 cases is not that different to what happened here.
"But the UK healthcare [system] was more about to cope with this, because although the rate of rise of these Covid-19 cases may have been similar in the UK and India, the absolute numbers of daily Covid-19 cases in India are far higher than they were in the UK in January 2021 - and the UK available healthcare resources per person is higher than in India," he said.
Professor Madhukar Pai, a global health expert at McGill University in Canada, said it was "devastating to see things get this bad in India," describing it as a "perfect storm".
"The current official figures are gross underestimates and the projections are terrifying. All of us know someone who is sick, and everyone is struggling to get medical care," he said.
India has been particularly caught short by its own home-grown variant, which spreads fast, like the British variant - which has also spread in the country.
Dr Jameel said this was a major factor, and said the public must take social distancing more seriously.
Otherwise? “Keep us in your prayers,” he said.
The prayers may be more fervent in India’s neighbouring countries like Nepal and Sri Lanka, with rising case loads.
But the whole world should be praying, others said. India’s crisis shows that everywhere remains vulnerable until vaccinated - particularly if the "pharmacy of the world" shuts its doors internationally, hitting vaccine roll-outs globally.
“We’re following the pattern of the 1918 pandemic,” warned Dr Ayoade Alajika, who is leading efforts to get vaccines to Africa.
“The first year killed about one million people. The second, some 50 million.”
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