Tracking COVID-19 with wastewater

How the virus’s chemical signature gives advance warning of the rise and fall of community transmission. As the pandemic’s second wave tightens its grip across the country, researchers, municipalities, and public health agencies are experimenting with a COVID-19 early warning system that tests wastewater for the virus’s unique chemical signature. Swab tests for the coronavirus are expensive and we aren’t capturing enough data for a true picture of how many people are infected, say epidemiologists.