Hello and welcome to more or less on the BBC World Service, with a programme that sweeps the world

with a spotlight of statistics, and I'm Tim Halford. I don't need to tell you that 2020 was a

bad year for many of us. According to official figures, the Covid pandemic killed 1.8 million

people last year. In India, at the peak of the crisis in 2020, cases hit around 100,000 a day,

but then in September, quite suddenly, cases and deaths began to fall.

Scientists and the media were busy deciphering what caused this decline and what contributed to

India's miraculous recovery from these dire projections from the first wave of the pandemic.

This is Professor Brahma Mukaji, Professor of Biostatistics and Epidemiology at the University of Michigan.

She works on an app called COV IND19, which brings together Covid data on India.

At one point of time, it went below 10,000 reported cases per day, and at that numbers also went down below 100.

India, with a population of 1.4 billion, had managed to get the pandemic under control. Roll on 2021.

Everybody was feeling very positive with the news of the vaccines and the colours steadily going down.

Many states were recording cases and deaths in single digits. So, at the beginning of February,

right around Valentine's Day, and I was seeing all of these images of Valentine's Departus in India

feeding through my social media, and I was also looking at our app. And we are even thinking that

is there enough data or need to continue running our app? We need to stop it now and the pandemic is over.

It was shortly after this that she spotted something in the numbers.

And suddenly at the middle of February, I started noticing this uptick.

It turned out that that was the beginning of an upward trend two months later.

The situation has really worsened. The medical system has collapsed.

It's not just India. Brazil and other countries are suffering from a surge in cases.

Today we are going to try to answer the question.

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