Jacinavicius Fernando de Castro, Bassini-Silva Ricardo, Muñoz-Leal Sebastián, Welbourn Cal, Ochoa Ronald, Labruna Marcelo Bahia, Barros-Battesti Darci Moraes
Laboratório Especial de Coleções Zoológicas, Instituto Butantan, São Paulo, SP, Brasil.
Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia - FMVZ, Universidade de São Paulo - USP, São Paulo, SP, Brasil.
Rev Bras Parasitol Vet. 2019 Oct-Dec;28(4):563-568. doi: 10.1590/S1984-29612019069.
Chiggers are ectoparasites of vertebrates and may cause trombiculiasis or transmit pathogens to their hosts. Specimens collected from rodents and marsupials were morphologically identified as Herpetacarus hertigi, Eutrombicula tinami, Kymocta sp., Quadraseta brasiliensis, Quadraseta falconensis, Quadraseta flochi, Quadraseta mackenziei, Quadraseta pazca, Quadraseta trapezoides, Quadraseta sp., Serratacarus sp., and Trombewingia bakeri. These mites were submitted individually to molecular analyses for the detection of bacteria of the genus Coxiella, Hepatozoon and Rickettsia. Samples were positive to Rickettsia only. Obtained sequences for the gltA (350 pb) and ompA (488 pb) genes were identical to "Candidatus Rickettsia colombianensi", a species previously detected in ticks. In addition, molecular identification of mites based on 18S rDNA sequences are provided for H. hertigi, Kymocta sp., Q. brasiliensis, Q. pazca, Q. trapezoides, Quadraseta sp., and T. bakeri for the first time. This is the first report of the detection of a Rickettsia sp. in chigger mites collected on rodents in Brazil.
恙螨是脊椎动物的体外寄生虫，可能导致恙螨病或向宿主传播病原体。从啮齿动物和有袋动物身上采集的标本经形态学鉴定为赫氏螨属、田鼠真恙螨、基莫克塔螨属、巴西四棱恙螨、猎鹰四棱恙螨、弗氏四棱恙螨、麦肯齐四棱恙螨、帕斯卡四棱恙螨、梯形四棱恙螨、四棱恙螨属、锯缘恙螨属和贝克氏恙螨属。这些螨类分别接受分子分析，以检测柯克斯氏体属、肝簇虫属和立克次氏体属细菌。样本仅对立克次氏体呈阳性反应。获得的柠檬酸合酶基因（gltA，350 pb）和外膜蛋白A基因（ompA，488 pb）序列与“哥伦比亚立克次氏体（暂定种）”相同，该物种先前在蜱虫中被检测到。此外，首次基于18S rDNA序列对赫氏螨属、基莫克塔螨属、巴西四棱恙螨、帕斯卡四棱恙螨、梯形四棱恙螨、四棱恙螨属和贝克氏恙螨属进行了螨类分子鉴定。这是在巴西啮齿动物身上采集的恙螨中检测到立克次氏体的首次报告。
