The Ixodid Ticks (Acari: Ixodidae) of Southern Africa

et al. 2020

Preprint

Abstract The abundance of tick populations in South Africa represents a probable risk for both animal and human health. Rickettsia spp. and Borrelia 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 Rickettsia and Borrelia species from ticks infesting domesticated animals in the Eastern Cape, South Africa. 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 Rickettsia and Borrelia species were carried out by amplifying fragments of gltA, ompA and ompB genes for Rickettsia and flaB gene for Borrelia spp. Thereafter, the positive ticks, Borrelia and Rickettsia ompB amplicons were sequenced and further analysed. Eight species of ticks belonging to three genera; Rhipicephalus, Amblyomma, and Haemaphysalis were identified. A total of 320 (27%) samples were confirmed positive for Rickettsia out of which 74 (23%) were positive for both ompA and ompB genes. Phylogenetic analysis of ompB revealed a high homology to rickettsial reference strains from GenBank, while there was no positive result for Borrelia. The generated sequences showed 99.1 to 100% homology with R. africae-KX227790 (100 %), R. parkeri - KY113111 (99.8 %), R. peacock (99.3 %) and R. slovaca - KJ675445, JX683122 (99.1 %) representative sequences in GenBank. The findings from this study revealed that ticks collected from domesticated animals were parasitized by Rickettsia species with possible zoonotic potential, which is detrimental to human health if bitten by infected ticks.

Section: Discussionsupporting

confidence: 84%

Section: Discussionsupporting

confidence: 83%

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

et al. 2020

Preprint

“…2). The three genera had previously been reported from South Africa 32,33 , thus our results is a confirmation that these genera are the predominant ticks species in the study areas. The emergence and geographical distribution of tick-borne zoonotic pathogens are controlled by the ecological distribution of their arthropod vectors.…”

Section: Rhsupporting

confidence: 90%

“…The most predominant tick species in this study was Amblyomma hebraeum and it had been formerly reported to be among the prevalent arthropod-vectors parasitizing different animals in South Africa, especially in the Eastern Cape 32,90, 91 followed by Rhipicephalus species 33,92 . The detection of R. africae genetic material in A. hebraeum and Riphicephalis species in this study is corroborated by the findings of Yawa et al 32 , thus confirming the role of A .hebraeum and Riphicephalis spp.…”

Section: Domesticated Animalsmentioning

confidence: 75%

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

et al. 2019

Preprint

BackgroundThe abundance of tick populations in South Africa represents a probable risk for both animal and human health. Rickettsia and Borrelia 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 Rickettsia and Borrelia species from ticks infesting domesticated animals in the Eastern Cape, South Africa. Morphological and molecular identification techniques were conducted on 1,200 tick samples collected from domestic animals before screening for the target bacterial pathogens. ResultsThe molecular identification of the tick samples was based on the amplification of the 12S rRNA mitochondrial DNA while detection of Rickettsia and Borrelia species were carried out by amplifying fragments of gltA, ompA and ompB genes for Rickettsia and flaB gene for Borrelia spp. Thereafter, the positive ticks, Borrelia and Rickettsia ompB amplicons were sequenced and further analysed. Eight species of ticks belonging to three genera; Rhipicephalus, Amblyomma, and Haemaphysalis were identified. A total of 320 (27%) samples were confirmed positive for Rickettsia out of which 74 (23%) were positive for both ompA and ompB genes. Phylogenetic analysis of ompB revealed a high homology to rickettsial reference strains from GenBank, while there was no positive result for Borrelia. The generated sequences showed 99.1 to 100% homology with R. africae-KX227790 (100 %), R. parkeri - KY113111 (99.8 %), R .peacock (99.3 %) and R. slovaca - KJ675445, JX683122 (99.1 %) representative sequences in GenBank. ConclusionThe findings from this study revealed that ticks collected from domesticated animals were parasitized by Rickettsia species with possible zoonotic potential, which is detrimental to human health if bitten by infected ticks.

“…In this study, a total of 1200 ticks comprising both adult and nymph that were mechanically removed from farm animals belonged to three genera; Rhipicephalus, Amblyomma, and Haemaphysalis were identified, with Rhipicephalus having the highest occurrence of 853 (71.1 %), followed by Amblyomma; 335 (27.9 %), and Haemaphysalis; 12 (1%) (Fig 2). The three genera had previously been reported from South Africa 32,33 , thus our results is a confirmation that these genera are the predominant ticks species in the study areas. The emergence and geographical distribution of tickborne zoonotic pathogens are controlled by the ecological distribution of their arthropod vectors.…”

Section: Phylogenetic Analysis Of Tick Speciessupporting

confidence: 90%

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

et al. 2019

Preprint

The abundance of tick populations in South Africa represents a probable risk for both animal and human health. Rickettsia and Borrelia 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 Rickettsia and Borrelia species from ticks infesting domesticated animals in the Eastern Cape, South Africa. 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 Rickettsia and Borrelia species were carried out by amplifying fragments of glt A, omp A and omp B genes for Rickettsia and fla B gene for Borrelia spp. Thereafter, the positive ticks, Borrelia and Rickettsia omp B amplicons were sequenced and further analysed. Eight species of ticks belonging to three genera; Rhipicephalus, Amblyomma, and Haemaphysalis were identified. A total of 320 (27%) samples were confirmed positive for Rickettsia out of which 74 (23%) were positive for both omp A and omp B genes. Phylogenetic analysis of omp B revealed a high homology to rickettsial reference strains from GenBank, while there was no positive result for Borrelia. The generated sequences showed 99.1 to 100% homology with R. africae -KX227790 (100%), R. parkeri - KY113111 (99.8%), R .peacock (99.3%) and R. slovaca - KJ675445, JX683122 (99.1%) representative sequences in GenBank. The findings from this study revealed that ticks collected from domesticated animals were parasitized by Rickettsia species with possible zoonotic potential, which is detrimental to human health if bitten by infected ticks.