Anaplasma infection of Bactrian camels (Camelus bactrianus) and ticks in Xinjiang, China

Abstract

BackgroundTo date, anaplasmosis has been reported to be a subclinical disease in Indian and Arabian one-humped camels (Camelus dromedarius) and llamas (Lama glama). However, no information on Anaplasma infection in two-humped Bactrian camels (Camelus bactrianus) in China has been published to date. The aim of this study was to investigate the prevalence of Anaplasma spp. in domestic Bactrian camels and ticks in Xinjiang, China.FindingsA total of 382 ticks were collected from the Bactrian camels and from environmental sources. Of these, 84 were morphologically identified as belonging to the Rhipicephalus sanguineus group and genetically identified (12S rDNA, 16S rDNA and the cytochrome c oxidase 1 genes) as R. sanguineus group ticks (temporally designated as Rhipicephalus sp. Xinjiang). PCR testing showed that 7.2 % (20/279) of the camels harbored Anaplasma platys DNA. However, microscopic examination revealed no A. platys inclusions in blood smears from the camels. The PCR prevalence of A. platys DNA was 9.5 % (6/63) in Rhipicephalus sp. Xinjiang from the Bactrian camels and 14.3 % (3/21) in Rhipicephalus sp. Xinjiang from the vegetation. A. platys DNA was not detected by PCR in other tick species (Hyalomma asiaticum, Dermacentor niveus and Hyalomma dromedarii), and no other Anaplasma species were detected in these samples.ConclusionsThis is the first report of A. platys in Bactrian camels in Xinjiang, China. The moderate positivity observed indicates that these animals might be a natural host for this pathogen in China.

Vector-borne bacteria in blood of camels in Iran: New data and literature review

“…Interestingly most genotypes differing in just one nucleotide were found in cattle, goat or blood-fed mosquitoes in China, but the Candidatus Anaplasma camelii genotype was not found in China. However, the largest diversity of similar genotypes was found in Asia (China, Philippines, Malaysia), and the same is the case with A. platys which differs only by one nucleotide [10,33,34,53,54]. The occurrence of identical genotypes in Iran, Bangladesh and Malaysia might suggest that Candidatus Anaplasma camelii did not originate in camels in the Middle East but in Eastern Asia.…”

“…Further studies for determining epidemiological role of camels and its zoonotic potential are recommended. This paper reviews the current knowledge on camels' tickborne bacteria including microscopy, serology and molecular studies.confirmed by DNA sequencing in camels are Candidatus Anaplasma camelii (genetically close to A. platys), A. phagocytophilum and A. ovis [10][11][12][13][14][15][16][17][18]. Clinical signs of natural infections are described as fever, pale and icteric conjunctiva suggestive of anaemia, dullness, anorexia, diarrhoea, loss of appetite, emaciation, coughing, lacrimation, rough hair coat, abortion, and/or infertility [7,19].…”

Ticks and associated pathogens in camels (Camelus dromedarius) from Riyadh province, Saudi Arabia

“…Indeed, the presence of A. platys DNA amplified from R. sanguineus (s.l.) collected from Bactrian camels has been previously reported [64].…”

A new quantitative PCR method for the detection of Anaplasma platys in dogs based on the citrate synthase gene

“…This bacterium was once housed in the genus Ehrlichia, but it has been recently reclassified based on a phylogenetic analysis of the 16S ribosomal DNA (rDNA) gene. 15 Although this agent is important for small animal clinics, A. platys has a broad host range, including cats, 11 cows, 12 camels, 24 and humans. 4,7,26 The most common diagnostic methods for canine infectious cyclic thrombocytopenia are the direct identification of the morulae in blood smears, serologic methods to detect antibodies, and DNA amplification by PCR.…”