Experts: ‘Need more checks in Covid-19 containment zones’

As the number of Covid-19 cases across Maharashtra continues to rise past the 1,000 mark, experts from across the country have suggested more testing and limited surveys in containment zones to understand the prevalence of the virus.

“Given the scale of the city and its high population density, certainly more testing is called for. We know that for every symptomatic case, there is a much larger number who remain asymptomatic,” said Gautam Menon, professor of physics and biology at Ashoka University, Sonepat (Haryana) and adjunct faculty at the department of biological sciences, Tata Institute of Fundamental Research, Colaba. “One expects that the current numbers of positive cases don’t accurately reflect the true numbers of those infected.”

Experts have pointed out that inadequate testing can result in asymptomatic cases silently spreading the disease. “The less testing we do, the less we know about the reach of the epidemic. Of course, it is also unfortunately true that widespread testing has its own logistical/financial difficulties,” said Dr Satyajit Rath, retired scientist from the Delhi-based National Institute of Immunology and adjunct faculty at the Indian Institute of Science Education and Research, Pune.

In addition to civic and government-run hospitals and research institutes, four private laboratories in Mumbai have been approved by the Indian Council for Medical Research to conduct real-time polymerase chain reaction testing for RNA virus (coronavirus). However, asymptomatic individuals are being discouraged from undergoing tests because the focus is to first test people displaying Covid-19 symptoms.

“Testing asymptomatic people would support and facilitate a general panic-driven tendency of those who can afford it to test themselves repeatedly, leading to a shortage of tests for those who need them, and also a false sense of security from a so-called ‘negative’ test,” said Dr Rath. “Testing asymptomatic people is probably best done, under the current circumstances, by state health care systems in a carefully planned fashion with epidemiological utility, rather than ‘on-demand’.

With Worli Koliwada emerging as the hotspot for Covid-19 cases in the city, the civic body has sealed over 280 containment zones. While family members, neighbours and those who have been in close contact with the Covid-19 patient undergo tests in containment zones, the remaining populace also has to observe the 14-day quarantine period.

Stating that it is not feasible to test everyone in containment zones at the moment, Menon also suggested undertaking limited surveys in that region, to understand the prevalence of the disease.

“One can then zoom in on regions where the infection appears to be larger, or where a cluster of cases have been reported, and test extensively there while trying to maintain some level of physical distancing in other areas so that spreading is prevented,” said Menon. “High-density urban regions are a particular nightmare when it comes to containing an epidemic. Mumbai is no different.”