Molecular detection and genetic variability of Ehrlichia canis in pet dogs in Xinjiang, China

Abstract

<jats:p>Background and Aim: As a tick-borne zoonotic pathogen, Ehrlichia canis has already posed a threat to public health and safety. This study aimed to clarify the prevalence and molecular characteristics of E. canis in pet dogs in Xinjiang, China. Materials and Methods: A total of 297 blood samples of pet dogs and 709 skin ticks (Rhipicephalus sanguineus sensu lato) were subjected to molecular detection using PCR for E. canis 16S rRNA gene, and then, positive samples were amplified, sequenced, and phylogenetically analyzed for E. canis gp36 gene. Results: The PCR detection showed that the positive rate of PCR was 12.12% (36/297) in blood samples and 15.23% (108/709) in tick samples, respectively. Based on the phylogenetic analysis of E. canis gp36 protein, these E. canis strains in different geographical regions of the world can be divided into Genogroup I and Genogroup II. Among them, the Xinjiang epidemic strain XJ-6 and 533, 36, 1055, Kasur1, and Jake strains were clustered into subgroup 1.1 of Genogroup I, while the XJ-2, XJ-21, and XJ-35 strains and the TWN1, TWN4, CM180, and CM196 strains were closely related and belonged to subgroup 2.2 of Genogroup II, displaying high genetic diversity. Conclusion: This is the first study focusing on the molecular epidemiology of E. canis infection in pet dogs, which revealed that E. canis infection had been occurred in Xinjiang, China. More importantly, this study confirmed that the substantial variability in immunoreactive protein gp36 from E. canis strains circulating in pet dogs.</jats:p>

Molecular discrimination and genetic diversity of three common tick-borne pathogens in dogs in Thailand

“…In the present study, A. platys (16.36%) was the most common canine tick-borne pathogen. The positive animals in this study were similar to the 11% (17/157) reported in dogs in the USA (Kelly et al, 2013), and were lower than those investigated by previous works; for example, 28% (42/150) in Pakistan (Malik et al, 2018) and 12.12% (36/297) in China (Mengfan et al, 2020). In Thailand, our results have exhibited that the occurrences of canine TBP infections of dogs were similar to those reported by previous studies.…”

Ehrlichia chaffeensis and Four Anaplasma Species With Veterinary and Public Health Significance Identified in Tibetan Sheep (Ovis aries) and Yaks (Bos grunniens) in Qinghai, China

“…These species have been detected in many ticks in China, for instance, Amblyomma testudinarium, Haemaphysalis yeni, Haemaphysalis longicornis, Ixodes sinensis, D. silvarum, Rhipicephalus sanguineus, and Rhipicephalus microplus (45)(46)(47)(48). In previous studies, E. canis infection was detected in Cervus nippon in Gansu (49), and high infection rates of E. canis and E. chaffeensis were reported in dogs, cattle, sheep, goats, donkeys, and humans in Xinjiang (9,18,50). Ehrlichia species were also detected in birds and small mammals in other parts of China (51,52).…”

Serological investigation of seven zoonotic pathogens in companion dogs in South Korea, 2018–2021

“…Although E. canis has a worldwide distribution, regional infection patterns are extremely varied. For example, seroprevalence rates as high as 12.2% have been reported in Xinjiang, China (Mengfan et al., 2020 ) while a rate of 1.33% was reported in Eastern China (Zhang et al., 2017 ). Further afield, E. canis seroprevalence rates appear to be low in Japan (Inokuma et al., 2003 ), North America and the United States (Little et al., 2021 ) but reached 30.83% in Mexico (Movilla et al., 2016 ).…”