loading page

Genetic evidence of spotted fever group rickettsiae in ticks collected from domestic animals in Eastern Cape, South Africa.
  • +1
  • BENSON IWERIEBOR,
  • Ayabulela Nqoro,
  • Anthony Okoh,
  • Larry Obi
BENSON IWERIEBOR
Sefako Makgatho Health Sciences University
Author Profile
Ayabulela Nqoro
University of Fort Hare Faculty of Science and Agriculture
Author Profile
Anthony Okoh
University of Fort Hare
Author Profile
Larry Obi
Sefako Makgatho Health Sciences University
Author Profile

Abstract

Background: Ticks have the propensity to transmit plethora of pathogens that have zoonotic potentials. Their distribution, diversity and the pathogens they transmit differs from one ecological location to another. SFG (spotted fever group) rickettsiae which are predominantly transmitted by different Ixodes ticks are responsible for emerging zoonotic diseases globally. Ticks were collected from domesticated animals in Raymond Nkandla Municipality, Eastern Cape, South Africa. The ticks were identified morphologically prior to DNA extraction and were molecularly identified by randomly selecting ticks from the morphologically delineated groups. To assess for the presence of tick-borne pathogens belonging to Rickettsia spp. by PCR (polymerase chain reaction) we used specific primer pairs targeting the gltA, ompA and ompB genes. The selected amplified ticks (according to morphological delineations), all positive ompB and forty three ompA amplicons were sequenced in a commercial sequencing facility. The obtained nucleotide sequences were edited and subjected to BLASTn for homology search and phylogenetic analyses were performed with MEGA 7 Version for evolutionary relationships with curated reference sequences in GenBank. Results: A total of 953 ticks collected in the study were delineated into three genera consisting of Amblyomma, Rhipicephalus and Hyalomma in decreasing order of abundance. The presence of Rickettsia DNA was detected in 60/953 (6.3%) from the three genera of ticks screened. Genetic analyses of the DNA sequences obtained showed that they have phylogenetic relationship to members of spotted fever group rickettsiae with R. africae, R. parkeri and R.tamurae being the SFGR (spotted fever group rickettsiae) detected in the screened ticks. Conclusion: This report shows that R. africae is the predominant spotted fever group rickettsiae in ticks collected from domestic animals in the study area and the human health impacts are not known.