Ticks and tick-borne pathogens of domestic ruminants in southern Africa: A systematic review of diversity, distribution, and epidemiology

The resurgence of tick-borne diseases remains a global concern, hindering livestock production across southern Africa and resulting in significant economic losses and threatening the livelihoods of small-scale farmers through reduced yields, higher treatment costs, and increased livestock mortality. This review synthesizes evidence on the genetic characterization, distribution, and epidemiology of ticks and tick-borne pathogens affecting domestic ruminants (cattle, goats, and sheep) in southern Africa. A search for peer-reviewed articles published between 2016 and 2025 was conducted across three electronic databases, and 21 studies met the inclusion criteria. Across the region, 28 tick species from six genera were reported, and Zimbabwe recorded the highest tick species richness, with the genus Rhipicephalus showing the highest species diversity. Otobius megnini was reported only in Lesotho, while several tick species were restricted and exclusive to South African cattle. Molecular screening showed that Ehrlichia ruminantium was the most frequently reported pathogen in cattle, with prevalence ranging from 29% in South Africa to 34% in Angola. Other important pathogens included Anaplasma spp., reported at 51% prevalence in goats in Lesotho, and C. burnetii, at 10% prevalence in cattle in South Africa. Piroplasm Babesia and Theileria spp. were also detected, although Theileria spp. were underreported, suggesting limited diagnostic sensitivity or a lack of transovarial transmission. Overall, this review reveals spatial distribution patterns and host-tick interactions, highlighting the need for an updated species checklist, improved surveillance, and stronger molecular diagnostic capacity to inform effective tick control and reduce the burden of tick-borne diseases while protecting livestock health across southern Africa.