A new piroplasmid species infecting dogs: morphological and molecular characterization and pathogeny of Babesia negevi n. sp.
A new piroplasmid species infecting dogs: morphological and molecular characterization and pathogeny of Babesia negevi n. sp.
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DOI：
10.1186/s13071-020-3995-5
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发表时间：
2020-04-21
影响因子：
3.2
通讯作者：
Aroch, Itamar
中科院分区：
文献类型：
--
作者：
Baneth, Gad;Nachum-Biala, Yaarit;Aroch, Itamar
巴贝斯虫病是一种由蜱传播的原虫感染，可引起人类、家畜和野生动物的贫血和危及生命的疾病。狗被至少六种特征良好的巴氏杆菌感染。导致临床疾病感染的piroplasmid种检测染色的血涂片从5只病犬从Israel. MethodsGeneticCharacteristics的piroplasmid进行PCR扩增的18 S rRNA和细胞色素c氧化酶亚基1（cox 1）基因，DNA测序和系统发育分析，提示调查寄生虫的identity. MethodsGeneticCharacteristics的piroplasmid。其中4只犬共感染波斯疏螺旋体（Dschunkowsky，1913），这是一种由蜱Ornithodoros tholozani Laboulbene & Megnin传播的回归热螺旋体。犬与B的共感染。persica提出了O.结果感染犬表现为发热（4/5）、贫血、血小板减少（4/5）和黄疸（3/5）。18 S rRNA和cox 1 piroplasmid基因序列的比较显示，从不同的狗和蜱扩增的序列之间的99-100%的同一性。系统发育树表明，一种以前未描述的巴贝虫属物种属于巴贝虫属西部类群（广义），与人类病原体邓肯巴贝虫Conrad，Kjemtrup，Carreno，Bethford，温赖特，Eberhard，Quick，Telfrom & Herwalt，2006密切相关，而与感染犬的康氏巴贝虫科Kjemtrup，温赖特，米勒，Penzhorn & Carreno，2006的相关性更中度。所检测到的梨质体包括四分体（马耳他杂交）、裂殖子和滋养体阶段，其平均大小大于其他犬巴贝虫属的阶段。属于巴贝（s.l.）和B。gibsoni Patton，1910，比其它犬巴氏巴氏杆菌（狭义巴氏杆菌）小。在212 O.调查的tholozani蜱中，11只（5.2%）携带有巴贝属新种的DNA。sp.的形态和遗传特征和系统发育分析的基础上进行了描述。该物种以以色列南部的内盖夫沙漠命名，那里是第一只受感染的狗的起源地。尽管在四只狗中存在合并感染，但第五只狗患有致命疾病，证明B。[咒语] sp.感染需要临床关注。定罪O. tholozani或另一种蜱种作为巴氏杆菌病的媒介。sp.，需要更多的研究。
IntroductionBabesiosis is a protozoan tick-borne infection associated with anemia and life-threatening disease in humans, domestic and wildlife animals. Dogs are infected by at least six well-characterized Babesia spp. that cause clinical disease. Infection with a piroplasmid species was detected by light microscopy of stained blood smears from five sick dogs from Israel and prompted an investigation on the parasite's identity.MethodsGenetic characterization of the piroplasmid was performed by PCR amplification of the 18S rRNA and the cytochrome c oxidase subunit 1 (cox1) genes, DNA sequencing and phylogenetic analysis. Four of the dogs were co-infected with Borrelia persica (Dschunkowsky, 1913), a relapsing fever spirochete transmitted by the argasid tick Ornithodoros tholozani Laboulbene & Megnin. Co-infection of dogs with B. persica raised the possibility of transmission by O. tholozani and therefore, a piroplasmid PCR survey of ticks from this species was performed.ResultsThe infected dogs presented with fever (4/5), anemia, thrombocytopenia (4/5) and icterus (3/5). Comparison of the 18S rRNA and cox1 piroplasmid gene sequences revealed 99-100% identity between sequences amplified from different dogs and ticks. Phylogenetic trees demonstrated a previously undescribed species of Babesia belonging to the western group of Babesia (sensu lato) and closely related to the human pathogen Babesia duncani Conrad, Kjemtrup, Carreno, Thomford, Wainwright, Eberhard, Quick, Telfrom & Herwalt, 2006 while more moderately related to Babesia conradae Kjemtrup, Wainwright, Miller, Penzhorn & Carreno, 2006 which infects dogs. The piroplasm forms detected included tetrads (Maltese cross), merozoite and trophozoite stages whose average size was larger than stages of other canine Babesia spp. belonging to the Babesia (s.l.) and B. gibsoni Patton, 1910, and smaller than other canine Babesia (sensu stricto) spp. Of 212 O. tholozani ticks surveyed, 11 (5.2%) harbored DNA of the new species of Babesia.ConclusionsBabesia negevi n. sp. is described based on morphological and genetic characterization and phylogenetic analyses. The species is named after the Negev desert of southern Israel, where the first infected dog originated from. Despite co-infection in four dogs, the fifth dog had fatal disease attesting that B. negevi n. sp. infection requires clinical attention. Incriminating O. tholozani or another tick species as the vector of Babesia negevi n. sp., would require additional studies.