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Rickettsial pathogens are amongst the emerging and re-emerging vector-borne zoonoses of public health importance. Though traditionally considered to be transmitted by ixodid ticks, the role of argasid ticks as vectors of these pathogens is increasingly being recognized. While bat-feeding (<i>Ornithodoros faini</i>) and chicken-feeding (<i>Argas walkerae</i>) argasid ticks have been shown to harbor <i>Rickettsia</i> pathogens in Zambia, there are currently no reports of <i>Rickettsia</i> infection in southern Africa from warthog-feeding (<i>Phacochoerus africanus</i>) soft ticks, particularly <i>Ornithodoros moubata</i> and <i>Ornithodoros porcinus</i>. Our study sought to expand on the existing knowledge on the role of soft ticks in the epidemiology of <i>Rickettsia</i> species through screening for <i>Rickettsia</i> pathogens in warthog burrow-dwelling soft ticks from two national parks in Zambia. The tick species from which <i>Rickettsia</i> were detected in this study were identified as <i>Ornithodoros porcinus</i>, and an overall minimal <i>Rickettsia</i> infection rate of 19.8% (32/162) was observed. All of the sequenced <i>Rickettsia</i> were identified as <i>Rickettsia lusitaniae</i> based on nucleotide sequence similarity and phylogenetic analysis of the citrate synthase (<i>gltA</i>) and 17kDa common antigen (<i>htrA</i>) genes. Utilizing all of the <i>gltA</i> (<i>n</i> = 10) and <i>htrA</i> (<i>n</i> = 12) nucleotide sequences obtained in this study, BLAST analysis showed 100% nucleotide similarity to <i>Rickettsia lusitaniae</i>. Phylogenetic analysis revealed that all of the Zambian <i>gltA</i> and <i>htrA</i> gene sequences could be grouped with those of <i>Rickettsia lusitaniae</i> obtained in various parts of the world. Our data suggest that <i>Rickettsia lusitaniae</i> has a wider geographic and vector range, enhancing to our understanding of <i>Rickettsia lusitaniae</i> epidemiology in sub-Saharan Africa.