SARS-CoV-2 in wastewater from Mexico City used for irrigation in the Mezquital Valley: quantification and modeling of geographic dispersion

Quantification of SARS-CoV-2 in urban wastewaters has emerged as a cheap, efficient strategy to follow trends active COVID-19 cases populations. Moreover, mathematical models have been developed that allow the prediction following temporal patterns viral loads wastewaters. In Mexico, no systematic efforts reported use these strategies. this work, we quantified rivers and irrigation canals Mezquital Valley, Hidalgo, an agricultural region where wastewater from Mexico City is distributed used for irrigation. Using quantitative RT-PCR, detected virus six out eight water samples five canals. Notably, showed general consistent trend having highest sites closer City, indicating main source contributes detection. data concentration river samples, generated simplified transport model describes spatial dispersion river. We suggest can be extrapolated other systems knowledge dispersion, at geographic scale, required. Our work highlights need improved practices policies related countries.