COVIDETECT is a project coordinated by the Ministry for the Environment and Climate Action, which brings together Águas de Portugal – leader of the consortium, Instituto Superior Técnico, Faculty of Sciences of Universidade de Lisboa, Águas do Tejo Atlântico, Directorate-General for Health (DGS), EPAL, Águas do Norte and Simdouro.

The Técnico researchers will be responsible for one of the most important tasks of the project: the validation of the virus detection method in wastewater. The project will help to anticipate new waves of the new coronavirus at a certain location, through wastewater testing, as well as to understand what the true amount of infection is out in the community, and to detect the reemergence of SARS-CoV-2, the causative agent of COVID-19.

Several research groups around the world consider that wastewater testing — used water that goes through the drainage system to a treatment facility – is a very useful tool in fight against the new coronavirus, helping to estimate more accurately the total number of infections, since most people will not be tested. Ricardo Santos and Sílvia Monteiro, the LAIST researchers involved in COVIDETECT, expressed their “intention to search the presence of SARS- CoV-2 in wastewater since the first reports of the presence of this virus in stool samples from patients with COVID-19, so we had already started to work in this area”, recalls Ricardo Santos.

The LAIST researchers are responsible for developing and validating the detection method that allows to analyse the wastewater in a more rigorous way. “After the initial research and development phase, we will monitor the wastewater in order to evaluate the presence of the virus”, says Ricardo Santos. “The samples produced by LAIST will be used later by the other partners of the consortium for SARS-CoV-2 modelling”, adds Sílvia Monteiro.

“COVIDETECT is a very interesting project, not only from a scientific point of view, but also from a public health point of view”, points out Ricardo Santos. “On the one hand, it is known that there is a prolonged presence of viruses in stool samples after the patients’ respiratory samples tested negative, which may give us a more accurate indication as to the end of the outbreak. “On the other hand, as people with mild or no symptoms are not diagnosed with the disease, the analysis of wastewater could give us a better idea of the true extent of the epidemic outbreak”, highlights the LAIST researcher. Sílvia Monteiro also recalls “there is evidence of viruses in stool samples before the development of the first symptoms”, so a quick monitoring of wastewater may show the virus circulation in the community more quickly. “This is important at this stage, because it will allow us to see if there will be a resurgence of SARS-CoV-2 in the next waves” she adds.

The project is expected to have a first phase of development and validation of the method of about one month, followed by the monitoring of five WWTPs [wastewater treatment plants] over the next six months, in parallel with the eco-epidemiological modeling of viral loads and sequencing of SARS-CoV-2 genomes present in wastewater. It is expected that this early warning system contributes to improve the country’s preparedness and response capacity to face potential future outbreaks.

Current projections point to a decrease in the spread of COVID-19 in the coming weeks. It is, therefore, very important that the team “takes advantage of this situation, in which the number of cases continues to rise, although not exponentially, in order to have the largest number of data that can be used in the future”, stresses Ricardo Santos.

The public health and social measures adopted by different countries have played an essential role in reducing the number of infections. However, it is normal that this number increases if countries begin lifting their sweeping restrictions. Therefore, routine wastewater surveillance could be used as a non-invasive early-warning tool to alert communities to new COVID-19 infections. According to LAIST researchers “wastewater can monitor the circulation of this virus, as well as others, even before the health authorities have the first confirmed cases”.