Sánchez Richard Said Thomas, Santodomingo Adriana Milena Santodomingo, Muñoz-Leal Sebastián, Silva-de la Fuente María Carolina, Llanos-Soto Sebastián, Salas Lucila Moreno, González-Acuña Daniel
Laboratorio de Parásitos y Enfermedades de Fauna Silvestre, Departamento de Ciencia Animal, Facultad de Ciencias Veterinarias, Universidad de Concepción, Chillán, Ñuble, Chile.
Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo - USP, São Paulo, SP, Brasil.
Rev Bras Parasitol Vet. 2020 Jun 26;29(2):e000120. doi: 10.1590/S1984-29612020029. eCollection 2020.
Small mammals play an essential role in the transmission and maintenance cycles of Borrelia spirochetes. In Chile, recent studies have characterized novel Borrelia genotypes in ticks collected from small mammals, a fact that suggests these vertebrates are hosts for spirochetes from this genus. Considering this evidence, the goal of this study was to determine the presence of Borrelia DNA in small mammals inhabiting northern Chile. In winter of 2018, 58 small mammals were captured in five localities. Blood samples were collected from rodents and DNA was extracted to determine the presence of Borrelia DNA by PCR targeting the flaB gene and rrs-rrlA intergenic spacer (IGS). From three individuals (5%), belonging to two rodent species of Cricetidae family (Phyllotis xanthopygus and Oligoryzomys longicaudatus), we retrieved three flaB and two IGS Borrelia genotypes. Phylogenetic analyses performed with both Maximum Likelihood and Bayesian inferences showed that our sequences grouped with homologous genotypes from the relapsing fever and Lyme borreliosis groups. Our findings suggest that P. xanthopygus and O. longicaudatus rodents may play a role as reservoirs for borrelial spirochetes in Chile.
小型哺乳动物在疏螺旋体的传播和维持循环中起着至关重要的作用。在智利，最近的研究对从小型哺乳动物身上采集的蜱虫中的新型疏螺旋体基因型进行了特征描述，这一事实表明这些脊椎动物是该属螺旋体的宿主。基于这一证据，本研究的目的是确定智利北部小型哺乳动物中疏螺旋体DNA的存在情况。2018年冬季，在五个地点捕获了58只小型哺乳动物。从啮齿动物身上采集血液样本并提取DNA，通过针对flaB基因和rrs-rrlA基因间隔区（IGS）的PCR来确定疏螺旋体DNA的存在情况。从属于仓鼠科的两种啮齿动物物种（黄臀叶耳鼠和长尾攀鼠）的三只个体（5%）中，我们获得了三种flaB和两种IGS疏螺旋体基因型。使用最大似然法和贝叶斯推断进行的系统发育分析表明，我们的序列与回归热组和莱姆病疏螺旋体组的同源基因型聚在一起。我们的研究结果表明，黄臀叶耳鼠和长尾攀鼠可能在智利作为疏螺旋体的宿主发挥作用。
