130 districts identified as Covid-19 hotspots home to nearly 400 million

The Centre on Friday listed 130 districts as hot spots of the coronavirus disease (Covid-19), down from the previously designated 170 "red zones", even as the number of "green zones" – areas that largely remain outside the spectre of the pathogen – decreased from 353 to 319, an announcement that came hours before the national lockdown was extended by two weeks, but with some relaxations.

The Union health ministry removed 92 districts from the 170 it classified as Covid-19 hotspots on April 15 and added 52 new districts to the list, leaving 130 red zones in the total 733 districts in the country. These 130 districts are home to a third of the country's population and cover a fifth of the geographical area, an analysis of the 2011 Census data by Hindustan Times shows. Nearly 400 million people live in these hot spots, which are spread across 22 states and Union territories (UTs), but only four states are home to more than half of them.

In the fresh classification, which will be followed by states and Union territories for a week from May 3, 284 districts have been identified as orange zones, up from 207 districts. All major metropolitan cities such as Delhi, Mumbai, Chennai, Kolkata, Hyderabad, Bengaluru and Ahmedabad have been designated as red zones because of high caseloads and clusters of infections.

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The zones were initially divided on the basis of total cumulative cases and the rate of doubling of cases: red zones were those where the numbers of Covid-19 infections and doubling rate were high; orange zones had fewer cases and greater doubling rate; and green zones were those where no case was reported in 28 days. The new list, however, was prepared by including other factors such as incidence and level of testing, and population density.

"This time, we have broadened the criteria. The areas have been labelled also keeping in mind the fact these should not become potential hot spots if relaxations are given as per the green zone criteria. Some places may be in green zone but their proximity to areas where case load is high makes them vulnerable, so those areas have also been designated as red or orange zones in the new list," said Lav Agarwal, joint secretary, health ministry.

Red zones will now be defined by taking into account the total number of active cases, the doubling rate of infections, the extent of testing and the surveillance feedback. To qualify as a green zone, an area would have had to report no new infections for three weeks. The classifications will be "dynamic" and updated at least weekly as conditions change, according to a letter by Union health secretary Preeti Sudan.

There are significant differences between the list of red zones shared on April 15 and the latest advisory. Even as the total number of red zone districts has decreased by 40, seven states have seen a rise in the number. West Bengal saw the highest rise, from four to 10. Tamil Nadu saw the biggest fall in the number of such districts – out of the 22 districts earlier classified as red zones, 13 have now been removed while three new districts have been added to the list, making the new tally 12.

The 400 million people in the 130 red zones live in more than 83 million households across nearly 2,500 towns and 120,000 villages. These comprise a third of all towns and a fifth of all inhabited villages in the country, according to the Census data.

To be sure, this is a close approximation for present times because the population figures would have changed since the Census was last conducted, and some district boundaries have also changed since then.

Among all states and UTs, Delhi is the only one fully classified as a red zone, other than Chandigarh which is a single district Union territory. After Delhi, West Bengal has the highest share of districts in red zones – 10 out of the total 23 districts, or 43%. Maharashtra and Andhra Pradesh follow with nearly 39% districts being red zones. In terms of absolute numbers, Uttar Pradesh has the highest number of red zone districts – 19 out of 75 – followed by 14 districts in Maharashtra (out of 36 districts) and 12 districts of Tamil Nadu (out of 37 districts).

Faridabad, Gautam Buddha Nagar and Meerut have been classified as red zones, while Gurugram and Ghaziabad are designated as orange zones.

The 14 most densely populated districts in India, according to the 2011 Census, have been classified as red zones. These include eight districts of Delhi, two districts of Mumbai, Chennai, Kolkata, Hyderabad and Chandigarh, all big urban clusters. Out of the 50 districts that have the highest population density, 25 have been classified as red zones.

Although the red zones are spread across large geographical areas, cutting across state boundaries, more than half of the people living in these red zones are in just four states – Maharashtra, Uttar Pradesh, West Bengal and Andhra Pradesh. Put together, 215 million people live in red zones in these four states, which is 54% of the total 400 million people in the red zones in India.

Also, there are no red zone districts in 14 states and UTs. These include 10 states – Goa, Himachal Pradesh and all eight states of the northeast – and four Union territories – Puducherry, Lakshadweep, Ladakh and Dadra and Nagar Haveli and Daman and Diu.

The revised list of Covid-19 hot spots was released ahead of the Centre's announcement of the extension of the national lockdown to break the chain of infections. While the red and orange zones will continue to have intensified contact tracing, doorstep surveillance and restrictions on movement, other areas will see considerable relaxations.

Sudan's letter to states and UTs read: "It is further highlighted that based on field feedback and additional analysis at state level, states may designate additional red or orange zones as appropriate. However, states may not relax the zonal classification of districts classified as red/orange as communicated by the ministry."

"It is important to ensure that we identify pockets of critical interventions for a focused management of Covid-19 at the field level," Sudan added.

Infectious disease experts say that lockdown has helped and now is the time to consolidate the gains. "It is useful if we are to utilise the time gained in identifying infected individuals isolating them, tracing contacts and quarantining them to interrupt the chain of transmission. We should be able to identify cluster transmission as people are confined to homes. Mathematical models have shown how extended periods of lockdown can decrease the peak. But if infected individuals are not identified and contained, then as soon as the lockdown is lifted, there would be a spurt of cases," said Dr Lalit Kant, infectious disease specialist and former head of the Indian Council of Medical Research.

(Inputs and image from hindustantimes.com)