New Delhi, India CNN  — 

In January this year, Kerala became the first Indian state to report a coronavirus case. Now, four months later, it claims it has flattened the curve.

Although India has been under a strict nationwide lockdown since late March, cases have continued to rise – the country of 1.3 billion now has more than 74,000 confirmed cases, including more than 2,400 deaths.

But Kerala, a thin strip on the country’s southern coast, has appeared to buck that trend.

Although its has a population of around 36 million – almost as big as Canada – it has reported just 519 cases and four deaths. As of Saturday, it had only 16 active cases, according to the state’s finance minister, Thomas Isaac.

Medical staff collect samples from people at a kiosk to test for Covid-19 in Kerala, India, on April 6, 2020.

For comparison, Maharashtra, the worst-affected state in India, has reported more than 23,000 cases, including more than 860 deaths.

Even accounting for their different population sizes, the states have very different outbreaks. Maharashtra has around 19 cases per 100,000, while Kerala has about 1. By way of comparison the United States, which has the world’s highest reported death toll, has around 415 cases per 100,000 people.

Experts say part of Kerala’s success is thanks to swift action and learning from past outbreaks. But Kerala also shows how disparate India is – and how much a person’s chances against the virus depend on where in the country they live.

What Kerala did right

At the center of Kerala’s response was woman who has been nicknamed “the coronavirus slayer.”

In the second week of January – before the state, and by extension India, had reported its first coronavirus case – Kerala’s Minister of Health and Social Welfare, KK Shailaja, noticed reports of a virus spreading in Wuhan, China.

With many students from Kerala studying in Wuhan, KK Shailaja suspected it was just a matter of time before the virus arrived in the state. In late January, the ministry set up 18 expert groups for different facets of the outbreak control, covering everything from contact tracing and screening, to logistics and mental health. “We planned everything,” she says.

From January 24, the government screened all passengers returning from China, and sent all symptomatic patients to designated isolation facilities. On January 30, Kerala confirmed its first coronavirus patient – a student who had been studying in Wuhan.

Authorities identified the first patient by screening all 172 passengers on a plane from Wuhan, and isolating three students who had minor symptoms in hospital. They were also able to trace more than 70 people who had been in close contact with the students, Shailaja said.