Study of the epidemiology and Its factor of Congenital Chagas Disease in South America

玻利维亚圣克鲁斯有多名先天性恰加斯病新生儿，我们继续调查检查其影响因素。本文对克氏锥虫（T.cruzi）慢性感染的母亲进行了抗体变化与寄生虫血症的相关性研究。结果：经PCR检测，克鲁氏锥虫感染慢性期孕妇血液中存在克鲁氏锥虫dna，多数（85.7%）经异种诊断显示为寄生虫。免疫荧光法检测血清抗体滴度变化维持在250 ~ 4096倍以上，抗体滴度较高，但临床表现明显异常的极少。经检查，PCR方法的临床诊断意义有待进一步评价，但对新生儿先天性恰加斯病治疗后的诊断意义明显。利用从感染三角瘤（Triatoma infestans）中分离得到的克氏锥虫，对实验动物进行了传染性和致病性检测。将从玻利维亚分离的克氏锥虫腹腔接种的小鼠表现出长期寄生虫血症，并作为慢性感染者存活。血液中检出的克氏锥虫甚至血清阳性的现象与玻利维亚的慢性病人相似。这些克氏锥虫广泛分布于南美洲，以遗传结构和地理上的差异而闻名。我们还分析了从先天性恰加斯病新生儿分离的克氏锥虫复数种群和从玻利维亚圣克鲁斯捕获的感染锥虫分离的克氏锥虫同工酶。18只股票中有8只属于第1组，有10只属于第3组，但建议它不是第3组的简单类别，而是与第2组的混合模型。

There is many Congenital Chagas' disease newborn at Santa Cruz in Bolivia, we continued survey examination about the factor. The chronic infected mother of Trypanosoma cruzi (T.cruzi) who is conceivable as career was examined about the relevance of the change of the antibody and parasitemia. As the result, the existence of T.cruzi -DNA was suggested by PCR method in the blood of pregnant women in chronic phase of T.cruzi infection, and most of them (85.7%) showed parasite even by Xenodiagnosis. Though the change of the serum antibody titer maintained 250 to 4096 or more times and comparatively high antibody titer by immunofluoresence assay, there were few who showed clearly clinical abnormality. According to the examination, the significance of the clinical diagnosis of PCR method need further evaluation, but there is clearly significance of diagnosis after the treatment of newborn of congenital Chagas' disease. Using T.cruzi isolated from Triatoma infestans (T.infestans), we examined about infectivity and pathogenicity to the laboratory animal. The mouse, which was, inoculated T.cruzi to the abdominal cavity that isolated from T.infestans in Bolivia showed long-term parasitemia and survived as chronic infector. The phenomenon that T.cruzi detected in blood even seropositive resembles the chronic patient in Bolivia. These T.cruzi widely spread in South America and are known for the difference of hereditary structure and geographically. We also analyzed the isozyme of the T.cruzi plural stocks, which are isolated from the newborn of congenital Chagas' disease and T.cruzi, isolated from T.infestans, which were captured in Santa Cruz in Bolivia. The 8 out of 18 stocks belong in Group-1, there are 10 stocks belong in Group-3, but it was suggested that it's not the simply category of Group-3, but the hybrid model with Group-2.