Scavengers, such as vultures and blowflies, are often described as nature’s environmental health department, clearing up decaying biological matter before it becomes a hygiene hazard.
But it’s no less plausible that animals that spend a lot of time in the vicinity of rotting flesh and faeces end up spreading rather than suppressing disease.
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It could go either way, depending on the scavenger, what they are scavenging and which diseases are about. Skunks feeding on bat carcasses have been shown to increase the incidence of rabies, for example.
On the other hand, long-toed salamanders scavenging the remains of frog tadpoles killed by Ranavirus reduce the likelihood that healthy tadpoles in the same pond will be infected.