West Bengal Epidemic Update: Reducing Cumulative Positivity Through Increased Testing Is The Need Of The Hour

The Wuhan virus epidemic situation in West Bengal entered consistent decline from late May 2021. Abatement was seen on all parameters. Case counts reduced significantly, as did the test positivity, and deaths.

Bengalis finally began to put behind the horrors of the second wave, to look forward to the monsoon, normalcy, a vintage mango season filled with Kishan Bogh, Malda, and Himsagar cultivars.

However, recent epidemic data from the state reveals that this declining trend has now slowed down. As the chart below shows, there has actually been an uptick in daily case counts this week (red curve). The test positivity (green curve) has stopped declining, to enter into a plateau, and the cumulative positivity (orange curve) is still at a high of 16 per cent.

This is a cause for concern, meriting immediate intervention by the state administration.

The reason for this abrupt reversal of trends is patently evident from the purple curve in the chart above – insufficient testing. It is the only monitoring tool available with state authorities anywhere, and should have been ramped up to over 1.75 lakhs a day by late April 2021 itself.

Unfortunately, the rate of daily sample collection, for a state as large and as densely populated as West Bengal, has been consistently and woefully inadequate throughout the second wave. At no point of time did daily testing cross even the bare minimum of one lakh tests a day, not even by a narrow margin. Indeed, on the contrary, testing has actually dipped by a third over the past month.

This is poor epidemic management practice. As Swarajya explained last week[1], the key to ensuring that a wave is exorcised post haste, while preventing a resurgence, is to maintain high levels of testing; in effect, we have to act as if the second wave never passed, if we are to prevent the onset of a third wave.

Unfortunately, the approach in West Bengal has been quite the opposite, with a distinct slackening seen almost as soon as the peak of the second wave passed. That is why the test positivity remained above a staggering 25 per cent for over a month between late April and late May; and that is why we are now seeing the virus raise its head in West Bengal again.

A second cause for concern is the cumulative positivity (CP; total cases by total tests). The standard barometer is that a state or a district may breathe easy once the CP dips below the 4-5 per cent band.

In West Bengal, though, the CP of the second wave is still at 16 per cent, and declining too slowly for any comfort (in contrast, the CP in both Uttar Pradesh and Bihar is down to 4 per cent this week, and reducing steadily).

The solution is self-evident: increase testing levels to over 1.25 lakhs a day within a week, and then ramp it up to around 1.75 lakhs a day within a fortnight.

If not, the contagion will linger within the populace, with the risk of an abrupt resurgence never more than days away, and West Bengal will be consigned to the misfortune of being stuck in a semi-permanent wave like Maharashtra or Kerala.

This vital step becomes all the more important with authorities announcing that the Delta-plus mutation is now a variant of concern. Chief Minister Mamta Banerjee has to somehow understand that the trick to defeating this virus is to deny it mutation space, to the extent possible.

Under no circumstances, then, can West Bengal become a new breeding ground for this new variant; we have enough woes with the old ones as it is.

Equally importantly, it cannot be that the virus is rooted out efficiently in some states, and not in others. The whole concept of lifting lockdown restrictions is premised upon the expectation that the situation would improve in all parts of the country, at around the same time. If that is not the case, and a few states continue to harbor the virus in critical mass, then we would only be delaying the inevitable.

Thus, unless cumulative positivities can be reduced to broadly the same levels, in roughly the same time, by adopting the same approach, in all parts of the Union, opening up will only lead to a resurgence of the epidemic. More so, considering that every construction project in the country hosts expert welders, fitters and grinders from West Bengal.

As a major manpower exporter, it is therefore contingent upon West Bengal to ensure that testing levels are increased swiftly to necessary levels, if the state’s economy is to be brought back on track, and if it is not to become a source of fresh infections for the rest of the country.