Martins Luciamáre P A, Marcili Arlei, Castanho Roberto E P, Therezo Altino L S, de Oliveira Janaína C P, Suzuki Rodrigo B, Teixeira Marta M G, da Rosa João A, Sperança Márcia A
Discipline of Parasitology, Marília Medical School, São Paulo, Brazil.
Am J Trop Med Hyg. 2008 Sep;79(3):427-34.
Triatoma infestans, the main vector of Chagas disease, has nearly been eliminated from Brazil. Nevertheless, other triatominae species are involved in the domiciliation process, including Triatoma rubrovaria in Rio Grande do Sul State (RS). Previous studies showed that 1.6% of the T. rubrovaria specimens collected at the rural district of Quaraí, RS, were naturally infected by Trypanosoma cruzi. In this study, five T. cruzi isolates obtained from infected triatomines were characterized molecularly and biologically. Genotyping of the T. cruzi isolates showed that they belong to lineage IIc of T. cruzi (TCIIc). Biological characterization showed miotropism and myositis during acute and chronic phases of infection, respectively. Virulence and mortality rates were variable among isolates. To our knowledge, this study corresponds to the first characterization of T. cruzi isolates from T. rubrovaria and the first description of TCIIc in the sylvatic cycle of T. cruzi from the southern region of Brazil.
克氏锥虫病的主要传播媒介——骚扰锥蝽，在巴西已几乎被消灭。然而，其他锥蝽亚科物种也参与到家栖化过程中，包括南里奥格兰德州（RS）的红带锥蝽。先前的研究表明，在南里奥格兰德州夸赖农村地区采集的红带锥蝽标本中，有1.6%自然感染了克氏锥虫。在本研究中，对从受感染锥蝽中获得的5株克氏锥虫分离株进行了分子和生物学特征分析。克氏锥虫分离株的基因分型表明，它们属于克氏锥虫IIc谱系（TCIIc）。生物学特征分析显示，感染的急性期和慢性期分别出现嗜肌性和肌炎。不同分离株的毒力和死亡率各不相同。据我们所知，本研究是首次对来自红带锥蝽的克氏锥虫分离株进行特征分析，也是首次描述来自巴西南部地区克氏锥虫野生动物循环中的TCIIc。
