This guidance supersedes the first April 2022 version. It is targeted at public health officials who want to understand and integrate complementary environmental surveillance (ES) into COVID-19 control strategies.

Routine diagnostic surveillance for COVID-19 has been augmented with ES in wastewater in many locations. ES provides additional evidence on virus in circulation at population level including presence or absence, early warning of increasing or decreasing trends, and information on variants of concern or interest. This guidance provides advice on:What situations ES has been shown to add value to public health decision makingOn what basis should an ES programme be initiated, maintained, modified, paused, or stoppedWhat is needed to plan and coordinate an effective ES programmeHow to carry out data collection, analysis, interpretation and communication of results