Wastewater-based Epidemiology for Infectious Diseases: The Foundations and Future Perspectives

Wastewater-base epidemiology may be a promising approach to capturing the dynamics of the spread of diseases as well as emerging mutants in a catchment. Herein, we describe the key components of the wastewater-based epidemiology of viral infectious diseases, including the optimization of the methodology of the detection and quantification of viral genomes and the development of a back-calculation model to estimate the number of infected individuals. Early warning based on the influent viral concentration in a wastewater treatment plant may be feasible when it takes longer than one week to tally the number of patients of the target infectious disease by the currently used sentinel surveillance under the infectious diseases control law. The variables of a back-calculation model are categorized into two types: common variables irrespective of the type of infectious disease and variables specific to the infectious disease including shedding profiles of viruses. Greater effort is required to develop a robust back-calculation model against variability and uncertainty due to environmental, geological, and personal differences.