Detection of Babesia caballi, Theileria mutans and Th. velifera in ixodid ticks collected from cattle in Guinea in 2017-2018

Intraerythrocytic protozoan parasites from the genera Babesia and Theileria may infect a wide range of animals and humans. The purpose of this study was to detect the 18S ribosomal RNA gene of Babesia spp. and Theileria spp. in ticks collected from household cows in the Republic of Guinea from 2017 to 2018 by PCR and then genotype the gene fragments by sequencing. A total of 907 ticks from 319 cows were collected in seven prefectures of Guinea (Boke, Faranah, Kankan, Kindia, Labe, Mamou and N'Zerekore). The following tick species on cattle were identified: Amblyomma variegatum (44.2%), Rhipicephalus decoloratus (34.7%), Rh. annulatus (10.3%), Rh. geigyi (7.3%) Hyalomma truncatum (2.4%), Rh. senegalensis (0.8%) and Haemaphysalis leachi (0.6%). Genetic markers for piroplasms were found in Am. variegatum, Rh. decoloratus, Rh. annulatus, and Rh. geigyi ticks, and the total infection rate for these ticks was 4.2%. The highest infection rate was found in Rh. annulatus ticks (10.9%). The piroplasms were genotyped as Babesia caballi, Theileria mutans and Theileria velifera by phylogenetic analysis of the 1150 bp 18S ribosomal RNA gene fragments. These pathogens were discovered in practically all studied prefectures in Guinea except for Mamou Prefecture. We propose that these ixodid ticks might play a major role in the transmission of piroplasm infections in domestic animals in Guinea.

Automated summary

This study detected Babesia and Theileria 18S ribosomal RNA genes in ticks collected from household cows in Guinea through PCR and sequencing, with an infection rate of 4.2%. The highest infection rate was found in Rh. annulatus ticks. Phylogenetic analysis revealed Babesia caballi, Theileria mutans and Theileria velifera as the genotypes present. These pathogens were discovered in all prefectures in Guinea except for Mamou Prefecture, suggesting the potential role of these ticks in transmitting piroplasm infections in domestic animals.