Pinto C Miguel, Ocaña-Mayorga Sofía, Lascano Mauricio S, Grijalva Mario J
Laboratorio de Investigación en Enfermedades Infecciosas, Escuela de Ciencias Biológicas, Pontificia Universidad Católica del Ecuador, Quito, Ecuador.
J Parasitol. 2006 Dec;92(6):1251-5. doi: 10.1645/GE-886R.1.
Small mammals trapped in domestic and peridomestic environments of rural Ecuador were screened for trypanosome infection by direct microscopy and hemoculture. Identification of species of trypanosomes was then performed by morphological characteristics and by polymerase chain reaction (PCR) assays. Of 194 animals collected, 15 were positive for infection (7.73%). Eight (4.12%) were infected with Trypanosoma cruzi (1 of 33 Didelphis marsupialis; 7 of 61 Rattus rattus). Eleven R. rattus (18.03%) harbored T. lewisi, 5 of which presented mixed infections with T. cruzi. Additionally, 1 of 3 Oryzomys xanthaeolus was infected with T. rangeli. No trypanosome infection was detected in Philander opossum (n = 1), Mus musculus (n = 79), Rattus norvegicus (n = 8), Akodon orophilus (n = 4), Sigmodon peruanus (n = 3), or Proechimys decumanus (n = 2). Many of the isolates belong to T. cruzi, the causative agent of Chagas disease, and R. rattus had the highest prevalence. Because of its abundance in the study areas, this species is considered an important reservoir for Chagas disease. This is the first report of T. lewisi and T. rangeli in Ecuador. This study is also the first to describe natural mixed infections of T. cruzi-T. lewisi.
通过直接显微镜检查和血液培养，对在厄瓜多尔农村家庭及周边环境中捕获的小型哺乳动物进行锥虫感染筛查。然后通过形态学特征和聚合酶链反应（PCR）检测对锥虫种类进行鉴定。在收集的194只动物中，15只感染呈阳性（7.73%）。8只（4.12%）感染克氏锥虫（33只南美袋鼬中有1只；61只黑家鼠中有7只）。11只黑家鼠（18.03%）携带罗氏锥虫，其中5只呈现克氏锥虫混合感染。此外，3只黄胸稻鼠中有1只感染兰氏锥虫。在北美负鼠（n = 1）、小家鼠（n = 79）、褐家鼠（n = 8）、奥氏稻鼠（n = 4）、秘鲁稻鼠（n = 3）或大长吻松鼠（n = 2）中未检测到锥虫感染。许多分离株属于恰加斯病病原体克氏锥虫，黑家鼠的感染率最高。由于其在研究区域数量众多，该物种被认为是恰加斯病的重要储存宿主。这是厄瓜多尔关于罗氏锥虫和兰氏锥虫的首次报告。本研究也是首次描述克氏锥虫 - 罗氏锥虫的自然混合感染情况。
