The Namaqua rock mouse (Micaelamys namaquensis) as a potential reservoir and host of arthropod vectors of diseases of medical and veterinary importance in South Africa.

Dina M Fagir,Eddie A Ueckermann,Ivan G Horak,Heike Lutermann,Nigel C Bennett

doi:10.1186/1756-3305-7-366

Dina M Fagir, Eddie A Ueckermann + Show 3 more

Open Access

https://doi.org/10.1186/1756-3305-7-366

Copy DOI

Abstract

BackgroundThe 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.MethodsIn 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.ResultsSmall 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.ConclusionM. 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.

Highlights

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
We investigated the ectoparasite community of the Namaqua rock mouse (Micaelamys namaquensis) in a nature reserve in the Gauteng Province, South Africa
Fleas and immature ticks were the most prevalent parasites recovered followed by mites and lice (Table 3)

Summary

Introduction

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. Within a host population parasites tend to exhibit an overdispersed distribution with only a fraction of the host individuals of a given species harbouring the majority of parasites [14,15]. Seasonal fluctuations in parasite prevalence and abundance are commonly observed and pronounced in ectoparasitic arthropods This may be linked to the life-cycle and seasonal fluctuations in temperature and humidity, which often determines the duration of the developmental stages in these parasites [16,17]. Seasonal patterns may be generated by the susceptibility of such ectoparasites to desiccation during periods spend off-host [16,18,19] Such periods may differ substantially between ectoparasite taxa and ixodid ticks can be encountered during the majority of their life-cycle in the environment. Changes in thermoregulatory demands and reproductive activity of the host in response to seasonal climate and fluctuations in food availability may contribute to the seasonal patterns observed in many ectoparasite species [1]

Objectives

Methods

Results

Discussion

Conclusion