Covid-testing: Is India scoring enough to flatten the curve?

As the Covid-19 pandemic rages across the globe, infecting over 8.9 million so far, India has emerged as the country with the fourth highest number of cases, with 4.25 lakh people testing positive. While most affected States and Union Territories are scaling up the number of tests to battle the pandemic, it may not be enough.

We looked at the testing data from Maharashtra, Kerala, Karnataka, Tamil Nadu, Delhi, Gujarat, West Bengal and Andhra Pradesh, between June 1 and June 19, 2020. Delhi, Maharashtra and Tamil Nadu — regions with growing number of cases — have more than doubled the number of tests since the beginning of June, and Andhra Pradesh has increased it about a third. While the number of tests conducted in Gujarat and West Bengal have increased, Kerala and Karnataka have shown a decline. In terms of the number of tests to population, Delhi, Tamil Nadu and Andhra Pradesh rank high. But the main metric to be considered to see if enough tests are being done is the number of tests to the number of positive cases, also called the positivity ratio. A high positivity ratio indicates adequate testing. According to WHO, 10-30 tests per confirmed case is considered the benchmark.

Delhi, Maha testing less?

Delhi and Maharashra seem to be doing fewer tests, with the positivity ratio in single digits. Gujarat and Tamil Nadu, with the ratio between 10 and 15, are also not too well placed either. Kerala (62), Karnataka (60), Andhra Pradesh (86) are the high ranking States.

Antony Kollanur, former health and nutrition specialist, UNICEF, says that low positivity rate (more people turning positive with fewer tests) could be due to two reasons. “First, it may mean that tests are being restricted to only sure-shot cases which are admitted and not testing adequate non-symptomatic contacts, family members, or high risk groups in contact with positive cases. Second, this may also mean that widespread community transmission is taking place.”

In terms of the absolute number of tests, Maharashtra ranks second after Tamil Nadu. Dr Shashank Joshi, Member on the Maharashtra Covid taskforce, says that looking at the density of the disease, it would be more in certain clusters. So, if early testing was in hotspots, that could be the reason for finding more positive people (in Maharashtra). “Presently, the testing is as per ICMR guidelines, which is to test every symptomatic patient and asymptomatic close contact only. The WHO suggests expansive testing. But it is not possible in the country to test everybody,” he adds.

Test more everywhere

Many experts from all parts of the country, however, think that testing is not adequate in India. There is a need to increase testing in Kerala by 20-30 per cent, says Dr Abraham Varghese, President, Kerala State Branch of the Indian Medical Association (IMA). “Particularly with the increase in the number of citizens arriving from affected countries and from red zones from other Indian States.”

A senior medical officer at one of the leading government-run hospitals in Ahmedabad, informed BusinessLine that tests are being conducted only on high-risk cases. “There are factors such as cost of a test. Also, we all know there is a constraint on bed capacity for Covid-19 patients. There is also a psychological factor that plays a role if more people are tested and we see number of cases rising.”

Dr Suresh Kumar, Consultant, Infectious Diseases, Apollo Hospitals, says that “we need to follow the Wuhan, China, model of testing where all the 11 million people were tested. In Tamil Nadu, as a pilot, this can be done in the zones in North Chennai that are worst affected. Depending on the success, this can be replicated in other parts of the city. Pooling testing could be another strategy, as was done in Wuhan as also in some US cities to screen many residents at once. This can be done here too.”

More tests done in cities

Is testing concentrated in cities where the cases are more with fewer testing in other areas? That seems to be the case.

Dr T Jacob John, eminent virologist and former professor at the Christian Medical College, Vellore, says, “Testing is ramped up when cases appear. Vellore had 100 positive on Sunday, and testing will be ramped up now. That’s the way it works. We will see a similar trend in Kancheepuram, Chengalpattu — suburbs of Chennai city.” He thinks that the virus will spillover to other districts — towns first and villages later.

Dr Amitabha Nandy, Virologist and Public Health Expert in Kolkata says that a look at the spread of testing labs in West Bengal makes it clear that most samples of Covid-19 are from Kolkata, Howrah and North and South 24 Parganas. Naturally, then, the percentage of positivity is not available to determine spread or exact number of infections.

With inputs from Delhi, Chennai Hyderabad, Mumbai, Bengaluru, Kolkata and Ahmedabad Bureaus

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