Noireau F, Bosseno M F, Carrasco R, Telleria J, Vargas F, Camacho C, Yaksic N, Brenière S F
Institut Français de Recherche Scientifique pour le Développement en Coopération, Casilla, La Paz, Bolivia.
J Med Entomol. 1995 Sep;32(5):594-8. doi: 10.1093/jmedent/32.5.594.
The risk of domestic transmission of Trypanosoma cruzi (Chagas) by sylvatic triatomines was assessed in an isolated area of the subandean region of Bolivia. None of the 390 residents examined had serological evidence of infection. Two sylvatic triatomine species, Eratyrus mucronatus (Stål) and Triatoma sordida (Stål), were found in houses and in peridomestic structures. The collection of nymphal instars of both species from some houses indicated possible domesticity. Microscopic examination of feces from 92 insects showed no parasites, and cultures from the guts of 30 insects were negative. Nevertheless, a polymerase chain reaction (PCR) test performed on the same fecal samples showed the presence of T. cruzi DNA in 19.1 and 12.5% of E. mucronatus and T. sordida, respectively. These 16 PCR-positive samples were hybridized with 2 T. cruzi-specific probes known from the domestic cycle in Bolivia (clones 20 and 39). At least 1 of these clones was identified in 7 bugs (5 E. mucronatus and 2 T. sordida). Moreover, no hybridization was observed with these probes in S E. mucronatus and 1 T. sordida samples that showed an amplified band by PCR. These data indicated that T. cruzi clones, genetically unrelated to clones 20 and 39, also were circulating in this area. Based on these results, the 2 sylvatic triatomine species encountered in Apolo should not be overlooked as possible local vectors of T. cruzi.
在玻利维亚安第斯山脉地区的一个偏远地区，对克氏锥虫（查加斯病）通过野生锥蝽进行家庭传播的风险进行了评估。接受检查的390名居民均无感染的血清学证据。在房屋和住宅周边建筑中发现了两种野生锥蝽，即具角锥蝽（Stål）和污色锥蝽（Stål）。从一些房屋中采集到这两种锥蝽的若虫表明它们可能已适应家庭环境。对92只昆虫粪便进行显微镜检查未发现寄生虫，对30只昆虫肠道进行培养结果为阴性。然而，对相同粪便样本进行的聚合酶链反应（PCR）检测显示，具角锥蝽和污色锥蝽中分别有19.1%和12.5%存在克氏锥虫DNA。这16个PCR阳性样本与玻利维亚家庭传播周期中已知的2种克氏锥虫特异性探针（克隆20和39）进行杂交。在7只昆虫（5只具角锥蝽和2只污色锥蝽）中鉴定出至少1个这样的克隆。此外，在通过PCR显示有扩增条带的7只具角锥蝽和1只污色锥蝽样本中，未观察到与这些探针的杂交。这些数据表明，与克隆20和39基因不相关的克氏锥虫克隆也在该地区传播。基于这些结果，在阿波洛发现的这两种野生锥蝽作为克氏锥虫可能的本地传播媒介不应被忽视。
