33% population in red zone, 43% in orange

While 17 per cent of the population in the red zone are in Maharashtra, 16 per cent are in Uttar Pradesh and 12 per cent in West Bengal.

According to the revised guidelines, green zones are those which have not reported any fresh case in the last 21 days, down from the 28 days earlier. Red zones are defined “by taking into account the total number of active COVID-19 cases, doubling rate of confirmed cases, extent of testing and surveillance feedback.”

The new classification means that some districts which have not reported cases for 14 days can still be listed in the red zone.

Health Ministry Joint Secretary Lav Agarwal said on Friday that the idea is to prevent an unforeseen surge in cases.

“Earlier, we had just two criteria for these classifications: total cases and doubling rates. But as the cases increase, the recovery rates change, sampling requirement increases, and we need to change sampling and identification criteria. It should be more broad-based, multi-factorial so that every eventuality for identifying critical areas for intervention are identified and no zone which can go on to become a problem area in the future, should be missed out. This is how we have defined red and orange zones now. It is critical to preempt an undercurrent of cases that can become unmanageable for the district tomorrow,” he said.

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The list is dynamic – there were 170 red zones on April 15, there are 130 now. However, 42 districts that used to be orange zones are now red zones.

A comparison with an Integrated Disease Surveillance Programme (IDSP) list from April 27 shows that 48 districts that had reported no fresh cases for the last 14 days have now been listed as orange or red. Lakhisarai in Bihar had reported no new case in 28 days on April 27, but is now an orange zone.

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Responding to a question on two districts in West Bengal which have not reported cases for 14 days but have been listed as red zones, Agarwal said: “We have used very comprehensive criteria. We have to be careful to not let things go out of hand in the future. There should not be a situation that we are testing less and we miss the undercurrent as cases keep growing. The density of the population too may hasten spread. We have identified potential future risk districts too and identified them as red zone. The challenge is whether we can delineate containment zones properly and do everything required with 100 per cent rigour,” he said.

“It is important to carry out proactive and stringent containment and to ruthlessly break the chain of transmission so that it does not go out of the district. However, outside the containment zone, it is possible that there could be some relaxations that the Ministry of Home Affairs can notify under the Disaster Management Act,” Agarwal said.