Earth has something like a billion species of bacteria, fungi and other microbes, and KK Shailaja was fascinated by each one of them.

To her, they were like atoms, the real, tiny things that make up and hold the world together.

But little did she imagine that she would one day be responsible for leading the fight against a shape-shifting, life-threatening virus that would ravage the world and threaten to overrun her home Kerala, a picturesque southern Indian state of 35 million people.

Fondly known as "teacher", Ms Shailaja scripted a rare success story in fighting the Covid-19 pandemic as the health minister of Kerala in 2020, which catapulted her to worldwide fame. The Guardian called her a "corona slayer", the Financial Times named her as one of the 12 most influential women of 2020. She was invited as a panellist at the UN Public Service Day and the UK's Prospect Magazine named her as the top thinker of the Covid age.

Her experiences - of leading a state through the pandemic and of growing up in India's only Communist state - make the backbone of her new political memoir, My Life As A Comrade, which released on Thursday.

As a physics teacher, scientific thinking always remained an integral part - a "default position" - to Ms Shailaja's decision-making process as the health minister, she told the BBC. "In my mind, Covid-19 reaching India was always inevitable and dealing with it was a matter of when, not if," she says.

But the die-hard Communist in her saw connections in everything. "In our lush, wooded neighbourhood, superstition, religion and socialism were never at odds; you could believe in all those things at once," she writes.

Ms Shailaja, who grew up in a small town in Kannur district, says she was deeply inspired by her Ammamma or grandma, a staunch Communist leader who helped tackle a smallpox outbreak in Kerala. Through her Ammamma, she learnt of the ways the Communist party tackled fear and misinformation and taught people how to deal with the infectious disease. Ms Shailaja said she never imagined that she would one day be in charge of doing the same thing.

In January 2020, Kerala reported India's first Covid-19 case - a medical student who had returned from Wuhan. At the time, coronavirus wasn't part of the popular lexicon and hardly anyone was discussing it in India, Ms Shailaja says. But in Kerala, the state government had already set up 18 rapid response teams, opened a control room and deployed medical officers at the state's four airports so that people could voluntarily declare any symptoms.

In a pandemic characterised by extreme uncertainty, Ms Shailaja said the government used its Nipah virus protocol - the state had successfully fought an outbreak in 2018 - "and made changes based on what was already understood about Covid".

Ms Shailaja said she had two options - either allow the virus to spread so that people could attain herd immunity. Or, contain its spread by detecting cases early, tracing contacts and quarantining the infected.

She knew a virus like this was deadly not only because it was highly transmissible, but because it was capable of exploiting a country's underlying shortcomings - a chronically underfunded health care system, unequal access, and a dearth of necessary safety nets.

Kerala fares better than most states on these indices, but the state is densely populated and 15% of its people are over 60 years of age. It is also majorly exposed to international travel and has some 17% of its working-age population employed outside, leaving the state vulnerable to outbreaks.

"Containment was the only way forward," she said, and the state decided to stick to the playbook of test, trace and isolate.

For some months, Kerala seemed primed to contain the virus. There were days when it reported no new cases. Testing was widespread, deaths were low and the health system - the most sophisticated in the country - was not overburdened. "We even managed to save people of 98 years of age," Ms Shailaja said.

But by mid-July, the state began reporting around 800 infections a day and by November, Kerala had recorded more than 500,000 infections.

In the summer of 2021 when a deadly second wave claimed thousands of lives, Kerala - a state with barely 3% of India's population - began accounting for more than half of India's new cases. Infections surged and showed no signs of abating even as the pandemic waned in other parts of the country - although the death rate remained low.

As the state floundered at controlling the virus, criticism against its government mounted.

Experts said Kerala's contact tracing mechanism, which had been its strong point during the first wave, had not shown the same efficacy in the second phase. Many said Kerala had also made the mistake of allowing festivals to go ahead, leading to mass gatherings. Even the policy response, experts said, had been anaemic - and though the state initially had managed to "flatten the curve", the time they bought was wasted.

Ms Shailaja said some of the criticism was unfair. "Because we did so well in the first phase, every reported Covid case in the state began to carry a whiff of failure."

Also, despite the rising number of cases, hospitals in Kerala were not overwhelmed and our mortality rate remained low throughout, she added.

But experts believe that Kerala's relatively low fatality rate did not tell the whole story. Reports alleged substantial undercounting of deaths in the state, claiming it was not adding suspected cases to the final count, and was attributing deaths to underlying health conditions.

In her memoir, Ms Shailaja rejects the allegations. "We did the best job we possibly could," she told the BBC.

Many experts too say that Kerala did an admirable job in controlling the spread of coronavirus when compared to the poor performance of other Indian states.

"I think the most important thing we did was also the simplest: we took Covid seriously," Ms Shailaja said.

But it was the state government's socialist foundation of "putting people at the centre of their policy", which made the difference, she added.

The health sector cannot exist in isolation, Ms Shailaja says. That's because diseases are not merely a battle between a host and a microscopic enemy, playing out in a person's body - they go beyond the individual and affect the entire society. And the virus cannot be fought only with vaccines.

"It requires more systemic reforms for overall social development. After all, everything is interconnected," she says.

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