Screening and phylogenetic characterization of tick-borne pathogens in a population of dogs and associated ticks in Egypt

Abstract

Background The incidence or recurrence of tick-borne diseases (TBDs) in animals and humans is increasing rapidly worldwide, but there is insufficient information about TBDs infecting dogs in Egypt. Thus, the present study was conducted to screen and genetically identify tick-borne pathogens (TBPs) in dogs and associated ticks by microscopic examination and polymerase chain reaction (PCR). Methods In Cairo and Giza governorates, 208 blood samples were collected from dogs of different breeds, ages, and sex. In addition, 1266 dog-associated ticks were collected (546 ticks were used to prepare hemolymph smears, and 720 ticks were kept in 70% ethanol until PCR analysis). PCR was applied to 124 dog blood samples and 144 tick pools prepared from 720 ticks. Results All ticks collected from dogs were Rhipicephalus sanguineus (s.l.). Microscopic examination revealed that TBP prevalence among dogs was 23.56% (49/208), including Anaplasma and Ehrlichia with 11.1% (23/208) and Babesia canis with 8.2% (17/208). Hepatozoon canis was not detected in blood smears. Co-infections with two pathogens were visible in 4.33% (9/208) of examined dogs. The prevalence of TBPs in hemolymph smears was 45.97% (251/546) including 35.89% (196/546) for H. canis, 8.1% (44/546) for B. canis, and 2.01% (11/546) for Anaplasmataceae (A. phagocytophilum, A. marginale, A. platys, and E. canis). The overall molecular prevalence rate of TBPs was 25.81% and 29.17% in the blood of examined dogs and in ticks, respectively. The molecular prevalence of Anaplasmataceae family, Babesia canis, and H. canis in dog blood samples was 19.35%, 6.45%, and 0.0%, respectively, while in ticks, it was 20.83%, 5.55%, and 2.8%, respectively. A sequential analysis identified six different species of TBPs, namely B. canis vogeli, Hepatozoon canis, A. phagocytophilum, A. marginale, A. platys, and E. canis. The obtained sequences were submitted to GenBank and assigned accession numbers. Conclusions The present study detected a wide range of TBPs (B. canis, H. canis, A. platys, A. phagocytophilum, A. marginale, and E. canis) that are considered a threat to domestic animals and humans in Egypt. Hepatozoon canis and A. marginale were reported in dogs and associated ticks for the first time in Egypt. Graphical Abstract

Spatio-Temporal Patterns of Ticks and Molecular Survey of Anaplasma marginale, with Notes on Their Phylogeny

“…scupense. To the best of our knowledge, the detection of A. marginale in R. sanguineus is exceptionally rare [46], and this pathogen has not been detected in Hy. scupense.…”

Epidemiological Survey on Tick-Borne Pathogens with Zoonotic Potential in Dog Populations of Southern Ethiopia

“…Since the sampled animals were asymptomatic, the positive dogs were probably in the chronic phase of infection. Although the prevalence was lower than those obtained in other African studies [ 11 , 40 , 42 , 45 , 56 ], the detection of this pathogen deserves attention not only because of the disease’s consequences for dogs’ health, but also because of the occasional reports of E. canis acting as a zoonotic agent [ 57 , 58 ].…”

“…In Africa some studies showed A. phagocytophilum in Rhipicephalus sanguineus , Haemophysalis elliptica and Hyalomma spp. [ 8 , 18 , 45 , 46 ]. In the dog population under this study, ticks belonging to the genus Rhiphicephalus and Haemophysalis were found, with the species R. sanguineus and H. leachi (unpublished data) highly represented.…”

“…Rhipicephalus sanguineus is also implicated as the main competent vector of this bacterium, but DNA of A. platys has been detected in other tick species. Anaplasma platys is distributed worldwide and has been detected in several dog populations in African countries, such as Algeria [ 37 ], Morocco [ 36 ], Egypt [ 45 , 51 ], Green Cape [ 52 ], Ivory Coast [ 53 ], Kenya [ 53 ], Uganda [ 17 ], Angola [ 54 ], Zambia [ 43 ] and South Africa [ 42 ], with the percentage of positivity changing in relation to the geographical area and the type of animal population considered [ 11 ]. The results of the present study demonstrated the circulation of this pathogen in dogs in Ethiopia.…”

Distribution and Prevalence of Anaplasmataceae, Rickettsiaceae and Coxiellaceae in African Ticks: A Systematic Review and Meta-Analysis

“…The following supporting information can be downloaded at: , Table S1: PRISMA checklist and additional checklist based on Migliavaca et al, 2020, guidelines; Table S2: List of papers excluded during full-text examination and relevant exclusion criteria; Table S3: Details of qualitative analysis; Table S4: Details of critical appraisal. References [ 102 , 103 , 104 , 105 , 106 , 107 , 108 , 109 , 110 , 111 , 112 , 113 , 114 , 115 , 116 , 117 , 118 , 119 , 120 , 121 , 122 , 123 , 124 , 125 , 126 , 127 , 128 , 129 , 130 , 131 , 132 , 133 , 134 , 135 , 136 , 137 , 138 , 139 , 140 , 141 , 142 , 143 , 144 , 145 , 146 ,…”