Are daily cases low because of inadequate testing?

Even as the Omicron variant of Covid-19 is resulting in a sharp increase in daily cases, the increase in daily testing is not keeping pace. Revised guidelines on testing requirements along with the exponential increase in cases are behind this mismatch in numbers, say experts.

All India Covid-19 cases for the month of January raced higher from 14,622 on January 1, 2022 to 2,48,963 cases as on January 17, 2022 (7-day moving average is considered here to smoothen daily fluctuations). This amounts to 16-fold increase in cases so far this month. But average testing per day increased just 52 per cent to 17,50,878 in the same period.

The current level of daily tests are pegged at almost 42 per cent below the peak testing level recorded in June 2021. The number of tests being done by the top 5 States with highest case-loads in January are also not seen to be ramping up on testing.

Also, the all India test positivity ratio jumped from 0.8 on January 1, 2022 to 10.7 by January 16, 2022. Test positivity is twice the national average in States such as Maharashtra and Kerala while it is thrice the all India positivity rate in West Bengal.

Earlier this month, the Indian Council of Medical Research had revised its guidelines and adopted a more targeted or precise approach that did not, for instance, require asymptomatic people to be tested.

Outpacing any health system

Explaining the mismatch in numbers, Dr Ambarish Dutta points out that for every two people tested, one is positive, unlike earlier waves including the Delta-induced one, where it was one for every 10 or 20 cases tested. “There is gross under-reporting and under diagnosis of cases, but this is not just in India, and is the case in other countries as well. The United States, for instance, has run out of tests because the Omicron variant causes infections that outpace any healthcare system,” Dr Dutta, Additional Professor (epidemiology) with the Public Health Foundation of India, told Business Line.

Pointing out that there was really no point in rampant testing, as most cases were asymptomatic, he said, health administrators need to monitor clinical symptoms and hospitalisation and treat symptomatic and vulnerable cases early.

Physician-epidemiologist Dr Chandrakant Lahariya observes that the number of cases become irrelevant after a point, as cases are asymptomatic and the treatment did not change on the testing of such cases. “Testing resources need to be used optimally and where they benefit the individual in terms of treatment being altered,” explains Dr Lahariya, a public policy and health systems expert.

He was not perturbed by the spike in home or self-testing, where people were possibly not reporting their results to the authorities. When there is wide-spread infection, he said, home testing had little value or benefit.

(With inputs from PT Jyothi Datta, Mumbai)

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