What followed was a 21-day hard lockdown, which would be extended several times to last a total of 68 days before some of the curbs were wound down with the first of the “unlock” phase.

India, like almost every other nation around the world, was reacting to a threat that was not entirely understood and the tools to fight it were all but missing. The decision had a simple objective: stamp out coronavirus outbreaks.

To understand India’s early lockdown and pandemic policies, it is crucial to first characterise them. India was perhaps the only major country that locked down before the virus took hold. The administration cited opinions from experts and said 21 days could be adequate to “break the chain of transmission”.

Today, after two years of various waves and types of lockdowns around the world, only China continues to follow such an approach, now described as “Zero Covid”. This strategy involves complete shutdowns and restrictions on movement till cases are reduced to zero, an objective that only China and island nations like New Zealand were able to achieve -- until the Omicron wave of 2022 spoiled it.

The basis for lockdowns

The concept of lockdowns harks back to 1918, when the world last recorded a respiratory virus pandemic with the Spanish flu outbreak. As in 2020, countries closed schools, places of worship and bars in 1918 to reduce social contact, and thus, virus transmission. Such measures that target public behaviour, including mandatory face covering and quarantining, are known as non-pharmaceutical interventions (NPIs).

NPIs involving lockdowns that were aimed at stamping out a disease completely have been used in the case of epidemics in the past – the 2002-2004 Sars outbreak and the Ebola epidemic have entirely been contained by locking down communities and geographies where the viruses spread.

A lockdown aimed at a similar elimination objective entered the Covid-19 playbook in the early days of the disease, in part due to the fact that there were no other tools to mitigate the crisis, but also because it was used in Wuhan, where the virus first spread.

Over the next months, there would be few regions in the world that did not replicate it. Most, unlike India, reacted after large outbreaks took hold in their cities, filling up hospitals.

‘Flatten the curve’

On March 16, the Imperial College of London published a report, titled “Impact of NPIs to reduce Covid-19 mortality and healthcare demand”, which was largely seen to have jarred the US and the UK into action, including a lockdown announced by the latter.

The Imperial report predicted up to 2.2 million deaths in the US and over 500,000 in the UK if the coronavirus was allowed to spread with no restrictions, a scenario that would lead to hospitals being overwhelmed.

But behind these startling numbers was a crucial nuance. Steps such as lockdowns (which the Imperial experts classified as “suppression” measures) were needed because of a specific objective -- reducing the impact of a pandemic on the health care system by “flattening the curve” of cases to under the threshold of medical care capacities.

The report added that strong NPIs would l not be sustainable and that until widespread vaccination is achieved, Covid-19 outbreaks would rebound once these policies are relaxed. Instead, it suggested, “adaptive hospital surveillance-based triggers for switching on and off population-wide social distancing”.

“Given local epidemics are not perfectly synchronised, local policies are also more efficient and can achieve comparable levels of suppression to national policies while being in force for a slightly smaller proportion of the time,” it added.

This was different from advocating for a lockdown that was rooted in a drive to stamp the virus out entirely, for which there was no scientific evidence. And it was different from the lockdown that India imposed in March 2020 in “every city, town, district and village”.

The lockdown, experts maintained, were a time to spruce up medical infrastructure.

The second wave and after

The true state of preparedness and the challenges that India faced were crystallised a little over a year later from the first lockdown was imposed, when the highly virulent Delta variant struck. Several areas, including the national capital Delhi, recorded an acute crisis of medical oxygen for over a week beginning April 23 as hospitals filled up beyond their capacities with critically ill patients.

Of India’s total Covid tally of 43 million infections and 517,000 deaths, 37% of cases and 33% of deaths took place in the April and May, 2021 at the height of the second wave of infections. At the beginning of this outbreak, a mere 12% of the people had received only one shot of a Covid-19 vaccine.

The experience of the bruising second wave, however, may have precipitated a quiet reorienting of India’s public health policymaking.

First, came a boost in vaccination. India’s vaccination drive stuttered from a lack of supplies for the most part of the first half of 2021, until the government secured more doses. In August and September came a huge boost, including an average one million dose a day that was delivered in mid-September.

By the end of 2021, on December 31, 65% of adults had been fully vaccinated.

The impact of the vaccines and the changes in policy were most visible during the Omicron variant outbreak. Three states reported their first Omicron detection on December 12, roughly a fortnight after the World Health Organization classified it as a variant of concern (VOC).

The first detections of Omicron, unlike the case of Delta, took place much before the variant triggered a wave of infections, signalling a significant lapse – the lack of adequate genomic surveillance – was addressed.

Between the two waves, the country beefed up its medical oxygen network, set up thousands of mini oxygen supply plants, formalised more adaptive response measures (Delhi put in place a colour-coded outbreak severity classification system) and pre-booked millions of doses of Covid-19 vaccines.

In other words, India had by now raised the threshold for its medical care capacities to absorb future shocks from the pandemic.

The message behind the measures

One of the successes of the Indian government’s pandemic policy lies in public health messaging. Between March 25 and June 30, the Prime Minister addressed the nation six times, exhorting people to be disciplined about Covid-appropriate behaviour. A year later, he made similar appeals to address what appeared to be rising vaccine hesitancy in the summer of 2021.

As a whole, the government carried out rigorous media campaigns, sending the public frequent reminders about wearing masks and maintaining social distance. The health ministry publicised data-driven risk maps and prominent medical community members issued public reassurances, especially on vaccines.

According to an analysis published in the journal PLOS One, such messaging helped in “creating the herd effect across pharma, economic, health and public safety sectors that enabled strict national lockdown”. These effects were also successful in rallying Indians to different causes, for example, “rapid production of PPE and masks for frontline workers… work from home and online learning”, the analysis found.

Predicting India’s pandemic path

At present, the number of new cases in India is at levels not seen since the end of April 2020, when the country was still in a hard lockdown and cases were yet to take hold outside of only a few pockets. Close to 84% of the adult population is now fully vaccinated.

While most are likely to have additional immune defences due to a natural exposure to the virus, the next critical policy question surrounds booster doses. An analysis by HT published this week showed that a little over third of the adult population above the age of 45 (regarded as the most vulnerable to the coronavirus) completed their full vaccination more than six months ago. This cohort will need to be covered with additional doses soon since scientific evidence has pointed to efficacy waning between six and nine months after the full course.

But perhaps the most important indicator for what the future may hold for India is in drawing contrasts with China, the only country comparable in terms of population size. The highly transmissible Omicron variant has blown past China’s zero Covid defences and poses a real threat to a population with fractional natural immunity.

In India, the Delta and the more innocuous Omicron waves have left a large pool of natural immunity, which explains the low level of cases even at a time of near-normal public activity and a potentially large group of people with some degree of diminished vaccine protection.

Whether this is the end of India’s pandemic story or a mere interval will depend not just on the evolutionary pathways the virus chooses, but also on the endurance of the defences the country has built, and the discipline it has honed in science and public health.