Monitoring seasonal viral diseases through wastewater is a detection tool brought to the public's attention by the Covid-19 pandemic, a long and tragic period that reinforced the legitimacy of what must now be considered a new epidemiological surveillance tool. Thanks to the wastewater from our toilets, known as blackwater, which is analyzed daily, it has been possible to observe the progression of Covid-19 variants within the population well before the emergence of coronavirus variants, and well before the outbreak of symptoms in residents of neighborhoods and/or entire cities. This monitoring has yielded results that are much earlier and more relevant than the aggregation of data from screening tests. It has made it possible to bypass a blind spot: that of asymptomatic cases. Wastewater has thus made it possible to track trends and anticipate the incidence of the disease in communities.
The tool, however, is not new. It has been used in the past to track other pathogens responsible for typhoid fever, of the polyomeliteIllicit drug molecules, such as ecstasy, cocaine, amphetamines, cannabis, and addictive tendencies, have also been regularly monitored in 128 major European cities by the European Union Drugs Agency (EUDAIn France, in addition to monitoring respiratory diseases, the SUM'EAU network has been systematically monitoring diseases such as measles, seasonal flu or bronchiolitis in wastewater treatment plants in metropolitan France since 2023.
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