Monkeypox is originally a disease which can be transmitted from animal to human (a zoonosis). However, in the outbreak in the spring of 2022 it is spread globally through human-to-human transmission.  Similar to an infection with smallpox, the infected person develops a skin rash. Starting as spots that turn into blisters. The blisters dry up and form a crust, leaving scabs that eventually fall off two to three weeks later. Also symptoms as fever, headache and muscle ache belong to an infection with monkeypox. 

Monkeypox virus DNA in sewage

RIVM studied whether the monkeypox virus can be found in sewage. In order to be able to detect the virus, the search focused on its genetic material (DNA). Over a period spanning from 23 May to 3 July 2022, the study looked at samples from eight different locations: two sewage treatment plants in Amsterdam, five Amsterdam districts and Amsterdam Airport Schiphol. Monkeypox virus DNA was found in sewage in all these locations. The monkeypox virus was more common in the samples from the Amsterdam locations than it was in the samples from Schiphol. 

Scabs or stools?

The research did not show how exactly the monkeypox virus ends up in sewage. This could be through washing the skin, with scabs ending up in waste water and thus in the sewerage system. Another possibility is that the virus is excreted in stools (poo).