Authorities denied reports on Tuesday that traces of the virus that causes Covid-19 have been found in sewage water samples collected in Lucknow. According to the reports, the Sars-CoV-2 virus was detected in wastewater samples from Rukpur Khadra in the Uttar Pradesh capital on May 19. Samples were also taken from Ghantaghar and Machhli Mohal areas. The sewage water samples were collected as part of a study by premier scientific body Indian Council of Medical Research (ICMR) and the World Health Organization (WHO) across several cities in the country, the reports added. Previously, the virus has been detected in wastewater samples in Hyderabad, Mumbai. While Sars-CoV-2 can be shed in the faeces of individuals with Covid-19, there is "no information to date that anyone has become sick with the viral infection because of direct exposure to treated or untreated wastewater", which includes water from toilets and sinks, according to America's Centers for Disease Control and Prevention (CDC). Lucknow's Sanjay Gandhi Postgraduate Institute of Medical Sciences (SGPGI) is among India's eight centres earmarked for testing sewage water samples for traces of the virus. The Lucknow samples were studied at the SGPGI lab, according to the reports. "Coronavirus spreads mainly via droplets of respiratory secretions. It has also been detected in stool samples of some patients, which is primarily a fragment of the virus. Presence of Sars-CoV-2 RNA in sewage samples has not been proven and require further studies. Currently there is no evidence that coronavirus spreads through water," Dr Ujjwala Ghoshal, the head of the microbiology department at SGPGI, said. The US CDC says sewage water testing has been successfully used as a method for early detection of other diseases, such as polio. Sars-CoV-2 can be shed in the faeces of "individuals with symptomatic or asymptomatic infection; therefore, wastewater surveillance can capture data on both types of infection", its website says. A section of experts believes information on the disease and its spread in a large population can be gained through wastewater sampling for the RNA of the virus. Such studies have been conducted in the US, UK, France, Italy, France and Canada, according to reports.
(This copy has been updated to accommodate the denial by officials that there is no conclusive evidence of traces of the virus being found in wastewater samples in Lucknow)