Analyzes of sewage samples from Lisbon, Cascais, Vila Nova de Gaia and Guimarães suggest that the covid-19 coronavirus, detected in untreated effluents, is disposed of in treatment plants, Águas de Portugal reported today.
For the study, more than 200 samples of sewage collected at the entrance and exit of five treatment plants that serve about 20% of the national population and areas with a high prevalence of infections were analyzed, according to a statement from the Águas de Portugal (AdP) group, who coordinated the work.
The results point to “the absence of genetic material” from the SARS-CoV-2 coronavirus “in the treated effluent”, which, according to the statement, “suggests that the treatment steps are efficient” in removing the virus from the sewers.
The AdP group adds that, although genetic material from the new coronavirus has been detected in sewers at the entrance to treatment plants, “it does not mean” that SARS-CoV-2 “is infectious or active and that it can spread” by water .
“In fact, there is no evidence at the date of the possibility of infection by SARS-CoV-2 through this route”, notes the note, stressing that the viral loads found in the sewage samples, before being treated, are “proportional to the reported concentrations similar studies under way in other countries “.
The work additionally monitored the circulation of the virus in the drainage networks of the hospitals Curry Cabral, in Lisbon, Eduardo Santos Silva, in Vila Nova de Gaia, and Senhora da Oliveira, in Guimarães.
In a subsequent phase, the AdP group and its partners in the project will carry out studies of “association of the detected viral loads” with the infected population in each area served by one of the five sewage treatment plants and with the patients admitted to the three hospitals.
“This process aims to establish correlations between the infected population, which potentially excretes viruses through feces and oropharyngeal secretions, with the viral loads in circulation in the sanitation systems”, says Águas de Portugal.
The work coordinated by AdP is part of the “Covidetect” project, launched in April with the purpose of monitoring the circulation of the covid-19 virus in the community through the surveillance of sanitation systems, and thus mitigating the effects of new outbreaks of the disease respiratory.
The AdP group has a scientific partnership with the Faculty of Sciences and the Instituto Superior Técnico, both from the University of Lisbon, in addition to entities that manage sanitation systems.
The Directorate-General for Health, the Portuguese Environment Agency and the Regulatory Entity for Water and Waste Services are members of the project’s advisory board, which runs until March 2021.
The covid-19 pandemic has already claimed more than 689,000 deaths and infected more than 18.1 million people in 196 countries and territories, according to a report by the French news agency AFP.
In Portugal, 1,738 people died of the 51,569 confirmed as infected, according to the most recent bulletin from the Directorate-General for Health.
Covid-19 is a respiratory disease caused by a new coronavirus (type of virus) detected in late December in Wuhan, a city in central China.
–
