Research is underway to develop and test methods for surveillance of genetic material from SARS-CoV-2 in wastewater and sludge. In contrast with case-based surveillance which generally only detects symptomatic COVID-19 cases, surveillance of wastewater and sludge would detect SARS-CoV-2 originating from both symptomatic and asymptomatic cases. Such surveillance can potentially be used to estimate prevalence at community level, identify a future surge or second wave of cases, identify regions where individual-level testing is inadequate, and eventually monitor uptake of vaccines. Similar techniques have been used in the global effort to eradicate polio. However, further research on methodology (sampling, analytical techniques, modelling) and interpretation of data is needed before this approach can be used to inform public health strategies. This approach is a complement to and not an alternative to testing in humans which remains important. To learn more about environmental surveillance of SARS-CoV-2 in wastewater, please read the WHO technical brief.
Want to know more about faecal-oral transmission of COVID-19?
Author: Jackie Knee