Evidence of pathogenic zoonotic tick-borne Rickettsia and Borrelia spp. in some communal farms in the Eastern Cape Province, South Africa

Abstract

<jats:title>Abstract</jats:title> <jats:p>The abundance of tick populations in South Africa represents a probable risk for both animal and human health. <jats:italic>Rickettsia</jats:italic> spp. and <jats:italic>Borrelia</jats:italic> spp. are well-known significant agents of emerging human tick-borne infectious diseases throughout the world. Nevertheless, the epidemiology of their infections has been underreported in South Africa, therefore, the aim of this study was to profile for zoonotic <jats:italic>Rickettsia</jats:italic> and <jats:italic>Borrelia</jats:italic> species from ticks infesting domesticated animals in the Eastern Cape, South Africa.<jats:bold> </jats:bold>Morphological and molecular identification techniques were conducted on 1,200 tick samples collected from domestic animals before screening for the target bacterial pathogens. The molecular identification of the tick samples was based on the amplification of the 12S rRNA mitochondrial DNA while those of <jats:italic>Rickettsia</jats:italic> and <jats:italic>Borrelia</jats:italic> species were carried out by amplifying fragments of <jats:italic>glt</jats:italic>A, <jats:italic>omp</jats:italic>A and <jats:italic>omp</jats:italic>B genes for <jats:italic>Rickettsia</jats:italic> and <jats:italic>fla</jats:italic>B gene for <jats:italic>Borrelia </jats:italic>spp. Thereafter, the positive ticks, <jats:italic>Borrelia</jats:italic> and <jats:italic>Rickettsia</jats:italic> <jats:italic>omp</jats:italic>B amplicons were sequenced and further analysed. Eight species of ticks belonging to three genera; <jats:italic>Rhipicephalus, Amblyomma, </jats:italic>and <jats:italic>Haemaphysalis </jats:italic>were identified. A total of 320 (27%) samples were confirmed positive for <jats:italic>Rickettsia</jats:italic> out of which 74 (23%) were positive for both <jats:italic>omp</jats:italic>A and <jats:italic>omp</jats:italic>B genes. Phylogenetic analysis of <jats:italic>omp</jats:italic>B revealed a high homology to rickettsial reference strains from GenBank, while there was no positive result for <jats:italic>Borrelia. </jats:italic>The generated sequences showed 99.1 to 100% homology with <jats:italic>R. africae</jats:italic>-KX227790 (100 %), <jats:italic>R. parkeri </jats:italic>- KY113111 (99.8 %), <jats:italic>R. peacock </jats:italic>(99.3 %)<jats:italic> </jats:italic>and<jats:italic> R. slovaca</jats:italic> - KJ675445, JX683122 (99.1 %) representative sequences in GenBank. <jats:bold> </jats:bold>The findings from this study revealed that ticks collected from domesticated animals were parasitized by <jats:italic>Rickettsia</jats:italic> species with possible zoonotic potential, which is detrimental to human health if bitten by infected ticks.</jats:p>