Modeling the number of people infected with SARS-COV-2 from wastewater viral load in Northwest Spain
Juán A. Vallejo, Noelia Trigo‐Tasende, Soraya Rumbo‐Feal, Kelly Conde‐Pérez, Ángel López‐Oriona, Inés Barbeito, Manuel Vaamonde, Javier Tarrío‐Saavedra, Rubén Reif, Susana Ladra, Bruno K. Rodiño‐Janeiro, Mohammed Nasser‐Ali, Ángeles Cid, María C. Veiga, Antón Acevedo, Carlos Lamora, Germán Bou, Ricardo Cao, Margarita Poza
Abstract
The quantification of the SARS-CoV-2 RNA load in wastewater has emerged as a useful tool to monitor COVID–19 outbreaks in the community. This approach was implemented in the metropolitan area of A Coruña (NW Spain), where wastewater from a treatment plant was analyzed to track the epidemic dynamics in a population of 369,098 inhabitants. Viral load detected in the wastewater and the epidemiological data from A Coruña health system served as main sources for statistical models developing. Regression models described here allowed us to estimate the number of infected people (R2 = 0.9), including symptomatic and asymptomatic individuals. These models have helped to understand the real magnitude of the epidemic in a population at any given time and have been used as an effective early warning tool for predicting outbreaks in A Coruña municipality. The methodology of the present work could be used to develop a similar wastewater-based epidemiological model to track the evolution of the COVID–19 epidemic anywhere in the world where centralized water-based sanitation systems exist.