India’s fight against Covid need to be supported with more data on testing

Given how limited the testing has been, it is surprising some in the medical community are calling a peak for the spread of the virus in cities like Mumbai. (Representative image)

With India now reporting close to 29,000 new infections a day, the virus is clearly spreading fast, prompting several state governments to re-impose lockdowns or put in place strict measures to restrict movement. In fact, the sharp rise in the positivity rate—new infections as a share of new tests—from 3% at the beginning of May to 10% now is evidence of increasing contagion. And, this is despite the fact that testing levels are very low for various reasons, one of them being the cost; in most states, only those persons who display symptoms and those who have been in contact with infected people are being tested. India tests just 8.6 persons per thousand population while the number is 122 for the US and 160 for Russia.

To be sure, there has been some improvement, and daily tests have more than doubled from 1.3 lakh on June 1 to 2.9 lakh today. In Delhi, for instance, testing has been ramped up more than four-fold from the 5,000 or so per day when the Centre stepped in to help the beleaguered Kejriwal government. Unfortunately, though, most of the tests being carried out are the less reliable rapid antigen tests (RAT); over the past month, only about two lakh RT-PCR tests were done while three lakh were RATs. Data accessed by The Indian Express show the former threw up a positivity rate of 30.5% and the latter a considerably lower 6.5%, making it clear that RAT miss out on a lot of the infected.

Given how limited the testing has been, it is surprising some in the medical community are calling a peak for the spread of the virus in cities like Mumbai. In fact, testing in Mumbai has been hopelessly inadequate at only around 4,000 a day; this has only recently been increased to 5,000. Only more testing can reveal the extent of the contagion. In Andhra Pradesh, for instance, the positivity jumped from 0.7% to 11% between June 2 and July 13 as the number of daily tests rose from 12,400 to 17,600. In West Bengal, the positivity more than trebled to 13.3% from 4.2% over the same period once testing rose from 9,495 day to 11,709 a day.

However, just 6.3 lakh tests have been done in West Bengal so far compared to 11.5 lakh in Andhra Pradesh. As it happens, in cities like Kolkata where the number of cases doubled in just a fortnight—few other big cities (Bangalore rose four times) show this sort of jump—there is no data on testing; as such, there is no information on whether positivity levels in the city are rising or not. Ideally, the state should provide all this information. But since it is not, ICMR should make this available since, in any case, all data is reported to it as well. Indeed, given discrepancies in data of other states—Delhi’s testing numbers and deaths have been revised several times—ideally, ICMR should reconcile all the data before putting it out.