The Covidetect pilot project has been running since last year and the preliminary results were presented on 26 May in Lisbon, at the Alcântara Wastewater Treatment Plant (WWTP), with those in charge explaining that the data collected in the water mirrored the daily evolution of the Covid-19 pandemic in recent months.
With the project it was possible to detect, in Gaia, variants of Covid originating in California and Nigeria.
The pilot project ends in August, but the Minister of Environment and Climate Change, João Pedro Matos Fernandes, who was at the ceremony, assured Lusa that the analysis of the WWTP waters will continue and be extended.
"Clearly yes," the minister said about the continuation of the project, whose results showed it was possible to detect the virus and its variants in the sewage water.
João Pedro Matos Fernandes stressed that not all treatment plants are prepared to make this detection, but that it is "absolutely essential" to extend the pilot project, so that water analysis becomes "a common rule for treatment plants across the country".
The treatment plants that will be built or renovated will have to be prepared for this type of analysis.
The pilot project was applied to five wastewater treatment plants, in Lisbon, Cascais, Gaia and Guimarães, and the circulation of the virus in the drainage networks of effluents from three hospitals was also monitored.
Health Minister Marta Temido, who also participated in the presentation of the preliminary results of Covidetect, considered it to be a "powerful tool" to fight the current pandemic and future pandemics, stressing the importance of acting early on risk phenomena.
The project is, he said, the opportunity to have a real-time notification system to health authorities, and has "enormous value" in the "pandemic response arsenal".
The next phase of the project involves disseminating the results and setting up a real-time alert system to notify health and environmental authorities of the re-emergence of the virus.
Covidetect was launched in April last year and funded by the European Union, being developed by a consortium that brings together companies from the group Águas de Portugal (AdP), the Faculty of Science of the University of Lisbon and the Laboratory of Analysis of the Instituto Superior Técnico.
A total of 760 wastewater samples were analysed between 27 April and 2 December 2020, "confirming that the data obtained for SARS-CoV-2 from untreated wastewater followed, in a very adjusted manner, the new daily cases reported for the regions where the wastewater treatment plants tested in this study are located," the officials said.
The project leaders have been collaborating with the European Commission in the initiative to make wastewater sentinels for the presence of the virus. The Commission has already made a recommendation for a common approach to surveillance for SARS-CoV-2 and its variants in wastewater in the European Union.
Nuno Brôco, vice president of AdP VALOR (an AdP group company and consortium leader), recalled that the European Commission has recommended that all member states implement this system by 31 October of this year, and added that Portugal is in a position to do so before then.
The recommendation indicates that plants that serve an area larger than 150,000 inhabitants should be monitored.
The official said that the current project, which is a pilot and did not involve a large number of wastewater treatment plants or continuous analysis, allows a few days in advance (four days for example) to have data on an increase in viral load in a particular location. "It aims to detect trends of growth or decrease" in viral load, he said.
Countries like Australia or New Zealand are already using treatment plants as "sentinels", creating an online system in which plants appear with a green colour, which turns red when genetic material from the virus is detected.
Photo: Kolforn (Wikimedia)