Rabinovich J E, Wisnivesky-Colli C, Solarz N D, Gürtler R E
National Institute for the Diagnosis and Investigation of Chagas Disease, Buenos Aires, Argentina.
Bull World Health Organ. 1990;68(6):737-46.
The daily probability (P) of transmission of Trypanosoma cruzi to a noninfected human host by an infected Triatoma infestans bug was estimated using field data from a 2-year longitudinal study carried out in a rural settlement of 20 households in Amamá, Santiago del Estero, Argentina. The following information was used for this purpose: the bug density and the proportion of infected bugs; the bug biting rate and the distribution of bites between humans and animals; the age-specific seropositivity to T. cruzi of the human population; and the actual number of new cases of human infection. The 2-year accumulated number of infective contacts per house estimated using a binomial model shows a statistically significant logistic correlation with the observed proportion of new cases per house. An average house where new cases of human infection were registered in the 2-year period had a P value of 0.0012, while an average general house (i.e., with and without new cases) had a P value of 0.0009. The observed range of P is discussed in terms of the chain of factors that affects the individual human risk of acquiring the infection and the possible entomological sampling errors.
利用在阿根廷圣地亚哥-德尔埃斯特罗省阿马马一个有20户家庭的农村定居点开展的一项为期两年的纵向研究中的实地数据，估算了受感染的克氏锥蝽将克氏锥虫传播给未感染人类宿主的每日概率（P）。为此使用了以下信息：锥蝽密度和受感染锥蝽的比例；锥蝽叮咬率以及人类和动物之间叮咬的分布情况；人群中针对克氏锥虫的年龄特异性血清阳性率；以及人类感染新病例的实际数量。使用二项式模型估算的每户两年累计感染性接触次数与每户观察到的新病例比例呈统计学上显著的逻辑相关性。在两年期间登记有人类感染新病例的平均每户的P值为0.0012，而平均普通家庭（即有和没有新病例的家庭）的P值为0.0009。根据影响个体感染风险的一系列因素以及可能的昆虫学抽样误差，对观察到的P值范围进行了讨论。
