A review of rabies in Southern African wildlife : reservoir hosts, transmission dynamics, and control implications

Abstract

Rabies is a fatal zoonotic disease that affects warm-blooded vertebrates and is caused primarily by members of the Lyssavirus genus (family Rhabdoviridae, order Mononegavirales). Three Lyssavirus species, namely Lyssavirus duvenhage and the putative lyssaviruses Lyssavirus matlo and Lyssavirus phyla, were first identified in insectivorous bat species in South Africa through lyssavirus surveillance activities. For the proposed and effective global elimination of dog-mediated human rabies by 2030; it is important to contextualize the pivotal role of wildlife in the maintenance and the likely spillover of rabies virus infections into naive dog populations that could potentially derail the progress toward rabies elimination. This review on rabies in wildlife identifies the current reservoir host species for sylvatic rabies, species predominantly affected by rabies (and non-rabies lyssaviruses) in southern African wildlife, and rabies transmission dynamics between these species. Canid rabies is maintained in a variety of southern African wildlife carnivores, including the black-backed jackal species (Canis mesomelas), side-striped jackals (Canis adustus), bat-eared foxes (Otocyon megalotis), and most recently, aardwolves (Proteles cristatus). In addition, the yellow mongooses (Cynictis penicillata) and slender mongooses (Galerella sanguinea) are reservoirs of the mongoose rabies virus (RABV) biotype (in South Africa and Zimbabwe, respectively). In Namibia, rabies virus infection is associated with wild ruminants, especially the kudu antelope (Tragelaphus strepsiceros), thereby posing a conservation threat to specific wildlife species. Oral rabies vaccination of wild carnivores using baited vaccines has been used as a complementary approach to mass dog vaccinations to mitigate infection spillover into domestic host species.