Even as the number of Covid-19 cases has been surging, India has ramped up testing significantly. This has resulted in the country conducting more tests than other countries such as US, Brazil, Russia and Peru that have ranked high in the total number of cases.
In the period between September 3 and September 20 this year, India tested 1.81 crore people for Covid-19. The US conducted 1.32 crore tests while Russia was next with 53 lakh tests. Brazil seems to have reduced its testing quite significantly in this period, with just six lakh tests.
Though India has increased the number of tests, the level of testing does not appear adequate, going by global standards. Russia scores high in positivity ratio (number of tests/number of cases), with the ratio at 38.8. India with positivity ratio of 11.6 and US with a ratio of 14.01, are much lower than the WHO threshold of 20. If the number of tests per million population is considered, then the US and Russia have done better compared to India and Brazil.
Of the Indian States, Uttar Pradesh has conducted the most number of tests between September 3 and 20, at 24.9 lakh, followed by Bihar with 21.29 lakh tests. Maharashtra (14.8 lakh), Tamil Nadu (14.2 lakh) and Andhra Pradesh (11.98 lakh) are other states that have conducted the most number of tests in September.
Are higher number of tests leading to a surge in new cases? “While t hat is true, we have not yet reached the levels recommended by WHO,” says Shahid Jameel, virologist and chief executive officer of DBT/Wellcome Trust India Alliance. “According to WHO, the outbreak would be in control if one positive case is found after every 20 tests or more. In India, this number has remained steady at one positive every 11 to 12 tests.”
LS Shashidhara, Dean of Research and Professor of Biology, Ashoka University, has a different opinion on this issue. “Because the level of infection in the population is so high, test positivity is very high. Even if we test only symptomatic and high-risk contacts, it would be still in very large numbers. In fact, we are not testing much outside metro cities. News from tier-II and tier-III towns and even villages of India are not that great.”
With testing equipment and kits getting cheaper, increasing the number of tests isn’t too hard. “Nearly 75 of testing kits in India are being procured from domestic manufacturers of India. So not only has the supply of kits improved since April, but we have also reduced our dependence on imports for our testing. This has also led to an increase in testing capacity with a daily average of more than one lakh tests being done in the country,” says Himanshu Sikka, Lead, Wealth, Nutrition and WASH, IPE Global.
“When the pandemic started in India, we had a handful of testing centres and access to only a few hundred testing kits per day. Now we have more than a thousand testing centres and nearly 1.5 million tests per day,” says Shashidhara. “Unfortunately, a substantial number of these tests are Rapid antigen-based tests, which are known for unacceptably high levels of false negatives.”
He thinks that the increase in our testing centres and number of tests per day have come in a bit too late to stop the rapid spread of the virus. Now the infection is rampant. Almost all sero surveys indicate that infection is above 25 per cent of the populations surveyed and in some cases above 50 per cent. As these surveys are done in the months of June onwards, it is clear that community transmission was happening even during the lockdown.