The epidemiology of tick in transmission of Enterobacteriaceae bacteria in buffaloes in Marshes of the south of Iraq.

Aim: This study aimed to investigate the role of ticks in transmission of Enterobacteriaceae bacteria in buffaloes in marshes of the south of Iraq.

Materials and Methods: This survey included 255 healthy and clinically ill buffaloes in marshes of the south of Iraq (Thi-Qar, Basra, and Misan provinces) between the periods from May 2017 to April 2018. Animals were clinically examined. Ticks, isolated from perineum and under tail, sent to the Department of Parasitology, College of Veterinary Medicine, University of Baghdad and University of Thi-Qar for taxonomy. Ticks were dissected, and all internal organs were removed aseptically by forceps to sterile tubes containing brain heart infusion broth and incubated at 37°C for 36 h and subcultured on blood and MacConkey agars at 37°C for 36 h. Biochemical tests including citrate, methyl red, indole, urease, triple sugar iron (H2 S), motility tests, and Gram stain were performed.

Results: Two species of ticks were identified. Hyalomma spp. (175; 68.63%) were significantly higher than Rhipicephalus spp. (80; 31.37%). Conversely, pathogenic bacteria in Rhipicephalus spp. (55; 68.75%) was higher than detected from Hyalomma spp. (113; 64.57%), but non-significant. The prevalence of Enterobacteriaceae bacteria in ticks on diseased buffaloes (110; 88.00%) was significantly higher than non-diseased (58; 44.61%). Escherichia coli (123; 73.21%) showed a significantly higher prevalence than Salmonella spp. (25; 14.88%) and Klebsiella spp. (15; 8.92%). There was no significant variation between Salmonell a spp. and Klebsiell a spp. The latter was significantly higher than Enterobacter spp. (5; 2.97%). The isolation rate of infected tick collected from buffaloes inhabiting marshes was 65 (66.32%), 45 (69.23%), and 58 (63.40%) from Thi-Qar, Basra, and Misan provinces, respectively, with no significant variation. July and August (71.05% and 72.97%) reported the highest among months, while November, December, January, and February recorded nil (0.00%). The summer season was significantly higher (72.72%) followed by autumn (62.06%) and spring (59.77%), while winter reported no any bacterial isolation (0.00%).

Conclusion: The high prevalence of Enterobacteriaceae bacteria isolated from hard ticks supports the probability of transmitting these bacteria to buffaloes in marshes of the south of Iraq.