Helminth composition and prevalence of indigenous and invasive synanthropic murid rodents in urban areas of Gauteng Province, South Africa

Abstract

Although synanthropic rodents such as the indigenous species, Mastomys coucha, and the invasive species, Rattus norvegicus, R. rattus and R. tanezumi, are well-known to be hosts to various micro- and macroparasites, their helminth parasite fauna is poorly studied in South Africa. In an attempt to remedy the situation, the aim of the present study was to investigate the helminth fauna of these sympatric rodent species, which were obtained from the informal settlements of Alexandra, Tembisa, Diepsloot and residential suburbs of Pretoria and Hammanskraal, Gauteng Province, South Africa. Helminths were recovered from the urinary bladder, liver and gastrointestinal tract and were identified morphologically and molecularly. The recovered nematodes were all rodent-specific and included Aspiculuris tetraptera, Eucoleus sp., Heterakis spumosa, Mastophorus muris, Nippostrongylus brasiliensis, Protospirura sp., Strongyloides ratti, Syphacia obvelata, Syphacia muris, Trichuris sp. and Trichosomoides crassicauda. Syphacia obvelata, a commensal nematode of laboratory rodents, was recovered from indigenous M. coucha. Strobilar stages of cestodes recovered included Hymenolepis diminuta, Hymenolepis nana and Inermicapsifer madagascariensis. Recovered metacestodes were strobilocerci of Hydatigera taeniaeformis from all three invasive Rattus species and coenurostrobilocerci of Hydatigera parva from M. coucha. An acanthocephalan, Moniliformis moniliformis, was recovered from R. rattus only. All rodent species examined showed high helminth infection prevalence (≥70%) with equal or higher nematode than cestode prevalence. Mastomys coucha, however, showed significantly lower cestode prevalence than Rattus species where they co-occur. Interspecific transmission of helminths likely occurs between invasive and indigenous rodents, and these rodents harbour several helminths that have zoonotic implications.