The successful implementation of GoAigua SARS Analytics is currently allowing the city of Valencia, Spain to anticipate coronavirus outbreaks and have a real-time view of their incidence among the population. The solution is an Early Warning System for the detection of SARS-CoV-2 in wastewater, showing its concentration in real time. It allows to identify the sources of the pandemic and to alert public authorities in order to anticipate outbreaks.
GoAigua SARS Analytics integrates third-party data (demographics, hospital occupancy rate, residences, reported cases...) in a single management point and provides or integrates solutions for planning and monitoring sampling processes, laboratory management software (LIMS) and dashboards.
After the first quantification of samples in April 2020, with results verified by the Spanish public research center IATA-CSIC, the validity of the method for determining the genomic units of the virus in wastewater was certified. Implementation in Valencia started at the beginning of May with the collaboration between the regional government (Generalitat Valenciana), the Spanish public research center CSIC and the water utility Global Omnium.
The correlation since February between the samples with positive results in Valencia’s WWTP and the numbers of cases reported was soon established. Results showed the presence of viral RNA in the city since February 24, suggesting a community transmission earlier than previously thought.
An average of 3 samples per week are being taken at each point in the city, measuring additional parameters (pH, temperature, TSS, COD, etc.) to normalize the results.
This enables Valencia City Council and health authorities to visualize the historical and real-time distribution in 24 areas of the city, evaluating infection rates. This way, the city can anticipate official data and assess risk at district level, considering not only the level of SARS-CoV-2, but also demographics or hospital capacity. Managers access all this information on the map, in an integrated environment.
GoAigua SARS Analytics.
Weekly analyses at the 30 sampling points reveal an uneven distribution of the virus by districts in Valencia. With this information, the City Council has decided to focus disinfection, control and prevention efforts on the most affected areas and key buildings, with a closer monitoring of social distancing and the launch of public awareness campaigns.
Evolution of SARS-CoV2 analysis results by sector in Valencia
With this method, Valencia carries out an early detection of the coronavirus, even among asymptomatic cases, since these also show up in the tests a few days before showing symptoms. During the last months it has been observed that a higher concentration of genomic remains of SARS-Cov2 in wastewater is reflected in an increase of positive PCR results a few days later.
Early detection versus PCR results
The granularity and accuracy of GoAigua SARS Analytics made it possible to detect that, compared to the low incidence in May, the presence of the virus was multiplied by 100 in some neighborhoods by the end of July.
According to the Councilor for the Water Cycle, Elisa Valía, Valencia aims to create a network of Spanish sentinel cities to exchange information obtained with the tool and provide solutions to a common challenge.
Our COVID-19's Early Warning System is allowing Valencia to anticipate outbreaks, and to concentrate policies and resources where they are most needed, without the need to test the entire population via PCRs.