Restrictive Testing Criteria

A country is at stage one of the spread of a disease if it only has imported cases -- those coming from another infected country. Stage two is localised transmission, in which those coming in contact with an imported case contract the disease. At stage three, community transmission takes place, when even those with no such contact with an imported case test positive for the disease. The fourth stage is an epidemic when a disease spreads more than what would normally be expected, based on the WHO’s criteria for that disease. Once it spreads across the world, it is termed a pandemic, as Covid-19 is now.

The Indian Council of Medical Research, India’s apex body for biomedical research, tested 826 symptomatic patients from hospitals to find out whether the virus was also affecting people in the community with no travel history or contact with an infected person.

The tests were negative, ICMR said in a March 19 press release. On March 18, 2020, the ICMR had said that negative cases showed that Covid-19 had not reached the stage of community transmission in India. With no community transmission, India does not need more widespread testing, the government posits.

“826 cases are really not enough to detect community transmission,” said Gautam Menon, a professor of physics and biology at Ashoka University, Sonepat. “We really need to test random people who exhibit a range of symptoms for Covid-19 not just the most extreme symptoms, because these will typically manifest in only a very small fraction of patients.”

For a country of India’s size, the ICMR’s cample is too small, said Om Shrivastava, an infectious diseases specialist at Jaslok Hospital in Mumbai.

South Korea, which had 8,413 total cases as of March 18, 2020, had tested 5,729.59 per million people compared to India. Taiwan, with 100 confirmed cases, had tested 18,812 samples.

“As far as testing for the localised transmission (stage-two) is considered, we are doing enough,” R Gangakhedkar, head of epidemiology and communicable diseases at ICMR, said on March 16, 2020. “We have not yet reached the stage (that would require) mass testing.”

“Today, till now based on our combined efforts there is no community transmission because we are able to verify cases,” said Lav Agarwal, joint secretary of the Ministry of Health and Family Welfare, at the March 19 press conference. “When community transmission starts, it becomes difficult to say from where did the patient catch an infection, which is not the case so far… You can easily say that there is no community transmission in India.”

It is unlikely that we have managed to track every case that has come in and it is possible that the disease is spreading in the community and the reason we have not picked it up is because most of these cases are yet to be found, Menon said.

“You need more testing, not less, to find out what is the status of your country,” in terms of stage 2 or 3, agreed Shrivastava.

The ICMR is more cautious. “ICMR is just trying to test, which we have found to be negative. We can’t say anything at this point about community transmission beyond that. We are trying to test further and increase the sample to get better results,” Rajni Kant, director of the Regional Medical Research Centre of the ICMR, told IndiaSpend on March 19.

The ICMR press release did say that surveillance is being expanded to include more areas, especially where Covid-19 cases have been reported, without giving any more details.