First molecular sequencing of Babesia gibsoni in ticks, Iraq.

Background: Tick is one of the most important ectoparasites distributed worldwide and plays an obvious role in the transmission of different infections to humans and animals as dogs.

Aim: This study conducted to molecular demonstration of Babesia gibsoni in ticks of stray dogs and phylogenetic analysis of study isolates to detect their identity to global isolates. Prevalence of ticks in dogs, identification of tick species, and their relationship to some risk factors were aimed, also.

Methods: A total of 97 stray dogs were inspected grossly to detect and collect ticks that existed in different body parts. After collection, all ticks were examined morphologically to identify their species, and then molecularly by the polymerase chain reaction (PCR) assay to detect B. gibsoni in different species of ticks. Local B. gibsoni isolates were sequenced, documented in the National Center For biotechnology information (NCBI) database, analyzed phylogenetically, and compared with the global GenBank-NCBI isolates.

Results: In the current study, ticks were detected in 43.3% of dogs, and were shown to be varied in number and distribution among different body parts of each dog. Concerning its distribution, ticks were observed significantly on the abdomen, ear, and perineal region. In relation to risk factors, ticks were increased significantly in dogs <6 months old in comparison to older dogs, males more than females; and in rural areas more than dogs of sub-urban and urban areas. Based on morphology, different tick species were seen including Hylaomma anatolicum (86.12%), R. sanguineus (11.99%), and Rhipicephalus turanicus (1.89%). Targeting the 18S rRNA gene, PCR assay reported 3.79% positive ticks to B. gibsoni that were seen in R. sanguineus (13.16%) and H. anatolicum (2.56%). Based on phylogenetic analysis data of five local B. gibsoni isolates, this study demonstrated their close relations to the global NCBI-BLAST B. gibsoni Iraqi isolate (ID: MN385424.1).

Conclusion: This represents the first Iraqi study that demonstrated molecularly B. gibsoni in different species of ticks that infected stray dogs.