Concern Grows That Human Medical Waste Implicated In Virus Spillovers

There is some concern among health experts that monkeypox and other infectious diseases could be transmitted to animals via human medical waste as cases of the virus surge outside of Africa, the president of the World Organization for Animal Health working group on wildlife said on Thursday.

Scientists are flummoxed as to what is driving the current crop of monkeypox cases - mostly identified in Europe so far - given they are predominantly not linked to travel to Africa, where it is endemic.

More than 550 confirmed cases of monkeypox have been reported by at least 30 countries in the latest outbreak, according to the World Health Organization (WHO).

As the virus circulates outside of Africa, there is an opportunity for spill back into animal populations, which could potentially make the virus endemic in countries beyond Africa.

"As we've seen with COVID-19, one thing that comes up is... disposable human medical waste because we are concerned about rodents picking this up," said William Karesh, speaking at a monkeypox briefing convened by the WHO.

"Like a rural local clinic that's putting their waste outside until it's disposed of properly later in the week," he added.

Countries in Africa have experienced sporadic monkeypox outbreaks since the virus was first discovered in humans in 1970. In Nigeria, there has been an ongoing outbreak since 2017.

The virus was discovered in laboratory monkeys in 1958, and since then various animal species including squirrels and rats have been identified as susceptible to it.

It is understood to have jumped to humans from the animals it which it circulates, but which species are implicated in the spillover remains unclear, Karesh said.

(The story has been refiled to clarify designation of the official in the first paragraph)