Abstract:
BACKGROUND : The role of endemic murid rodents as hosts of arthropod vectors of diseases of medical and veterinary
significance is well established in the northern hemisphere. In contrast, endemic murids are comparatively
understudied as vector hosts in Africa, particularly in South Africa. Considering the great rodent diversity in South
Africa, many of which may occur as human commensals, this is unwarranted.
METHODS : In the current study we assessed the ectoparasite community of a widespread southern African endemic,
the Namaqua rock mouse (Micaelamys namaquensis), that is known to carry Bartonella spp. and may attain pest status.
We aimed to identify possible vectors of medical and/or veterinary importance which this species may harbour and
explore the contributions of habitat type, season, host sex and body size on ectoparasite prevalence and abundance.
RESULTS : Small mammal abundance was substantially lower in grasslands compared to rocky outcrops. Although the
small mammal community comprised of different species in the two habitats, M. namaquensis was the most abundant
species in both habitat types. From these 23 ectoparasite species from four taxa (fleas, ticks, mites and lice) were
collected. However, only one flea (Xenopsylla brasiliensis) and one tick species (Haemaphysalis elliptica) have a high
zoonotic potential and have been implicated as vectors for Yersinia pestis and Bartonella spp. and Rickettsia conorii,
respectively. The disease status of the most commonly collected tick (Rhipicephalus distinctus) is currently unknown.
Only flea burdens differed markedly between habitat types and increased with body size. With the exception of lice,
all parasite taxa exhibited seasonal peaks in abundance during spring and summer.
CONCLUSION : M. namaquensis is the dominant small mammal species irrespective of habitat type. Despite the great
ectoparasite diversity harboured by M. namaquensis, only a small number of these are known as vectors of diseases of
medical and/or veterinary importance but occur at high prevalence and/or abundance. This raises concern regarding
the potential of this host as an endemic reservoir for zoonotic diseases. Consequently, additional sampling throughout
its distributional range and research addressing the role of M. namaquensis as a reservoir for zoonotic diseases in
southern Africa is urgently needed.
