Molecular screening of ticks for the presence of Rickettsia species: A public health concern: A public health concern

© 2017 by the Asian Pacific Journal of Tropical Disease. Objective: To profile ticks collected from domestic animals and vegetation for the presence of Rickettsial pathogens. Methods: Ticks were collected from domesticated animals and from vegetation in some selected communities. A total of 900 adults and nymphs ticks were collected. They were identified by taxonomic morphological criteria and screened for the detection of Rickettsia genetic material using citrate synthase (gltA) gene specific primers to produced 610 bp amplicons which were sequenced and analyzed. Results: The ticks collected were identified as belonging to three genera which were Rhipicephalus, Amblyomma, and Hyalomma, in decreasing order of their abundance. Rickettsial genetic material was detected in 15/900(1.67%) of the samples. Analyses of the generated sequences showed that five are phylogenetically related to members of the spotted fever group (SFG) rickettsia while the remaining ten sequences were Candidatus Rickettsia spp. whose pathogenic potentials are not known. The SFG rickettsia was of the genera Rickettsia akari and Rickettsia raoultii both being reported in South Africa for the first time and also in Rhipicephalus spp. as a vector. Conclusions: This finding thus shows that ticks in South Africa harbor Rickettsia akari and Rickettsia raoultii and are capable of transmitting it to infested humans.