1st in India: Sewage in 45 Bengaluru wards to be tested for coronavirus clusters

Karnataka will start testing sewage water to assess the prevalence of Covid-19 with a surveillance system in Bengaluru where traces of the novel coronavirus will help identify potential clusters and any alarming variants that may spring up due to the mutation.

To begin with, the testing will be done in 45 wards, and the system will eventually cover over 75% of Bengaluru’s 90 lakh residents by generating over 90 data points per week, which would signal the emergence or exit of Covid-19 cluster from an area, said Rakesh Singh, Additional Chief Secretary, Urban Development Department. “We are happy to launch this model in Bengaluru, the first in India,” he added.

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Singh said wastewater testing could be a cost-effective early warning system to assess the increase in Covid-19 cases before the number of official cases goes up. “Early identification of these clusters can help guide the Covid-19 response and give policymakers the information they need to better allocate the limited pandemic resources,” he said.

Officials hope the exercise will help avoid city-wide lockdowns by focusing on micro-containment zones, where restrictions are imposed on a small area.

The project has been launched in association with PCMH Restore Health and Wellness, which is part of the CovidActionCollab collective, and supported by United States Agency for International Development (USAID) and the Skoll Foundation.

Experts from the World Health Organization, the National Institute of Virology and other agencies will be part of the initiative, said Shan Venkat, co-founder of PCMH Restore Health and Wellness.

Tracing the virus

Venkat said samples would be pulled from 45 wards every day for the next year. “We will not only check for the traces of the virus but also do genome sequencing. The early warning system will identify the infected areas and give an indication of major variants of concern, if any,” he explained.

When a different variant of the virus is found, experts will collaborate to study it and provide key insights that will help make better policy decisions. “We will have a meeting with the BBMP chief commissioner every month where our findings will be discussed and decisions taken,” Venkat said.

The project would involve tracing the origin point as far as possible. For example, if the lab finds the virus or its trace in the main sewage line, the next step will involve pulling samples from all the trunk lines, lines from a particular ward, area or even a road.