Since at least 2011, the Dutch test wastewater of cities for traces of drugs, such as cocaine and XTC, and use this to inform public policy.

Already in 2009 it was known that coronaviruses can survive and remain infectuous in sewage water for up to two weeks.

Early covid wastewater research mostly focuses on waste water and stool as a possible infection vector, and in March 3rd the WHO suggested that COVID patients use their own toilet, to avoid spread through aerosolization during flushing, and to increase chlorination efforts of sewage systems.

From the first outbreak of SARS-CoV, it was found that apartment plumbing can be an infection vector, and due to this, in Hong Kong, people suggest closing the toilet lid before flushing.