Booth M, Mayombana C, Kilima P
Department of Public Health and Epidemiology, Swiss Tropical Institute, Basel, Switzerland.
Trans R Soc Trop Med Hyg. 1998 Sep-Oct;92(5):491-5. doi: 10.1016/s0035-9203(98)90886-0.
A study of helminth infections was undertaken among 3244 schoolchildren from 28 schools in Morogoro Rural District, Tanzania. Schistosoma haematobium was the most common infection, followed by hookworms, Ascaris lumbricoides, S. mansoni, and Trichuris trichiura. Infection prevalence of each species varied among schools and age groups, but not between sexes. There was no relationship between the prevalences of different infections among schools, except for a strong negative correlation between the prevalence of hookworm and S. mansoni infections. Within each age group, there was little excess overlap in the distribution of each infection; thus the number of multiple infections was low whereas the number of individuals harbouring at least one infection was relatively high. More children than expected carried infections of A. lumbricoides and S. mansoni, and the clustering effect increased with age. Only 2 schools had high overall infection prevalences of both geohelminths and schistosomes. Logistic regression analysis of morbidity and parasitological data indicated that individuals with multiple species infections were not at increased risk of morbidity (on a multiplicative scale) compared to individuals with single species infections. This was attributed in part to the low egg counts observed for each parasite species. The results implied little interaction between schistosome and geohelminth infections in the region, both in parasitological terms and in the context of their combined effects on health. Implications for the feasibility and benefits of combined control of geohelminths and schistosomes are discussed.
在坦桑尼亚莫罗戈罗农村地区的28所学校的3244名学童中开展了一项蠕虫感染研究。埃及血吸虫是最常见的感染类型，其次是钩虫、蛔虫、曼氏血吸虫和鞭虫。每种寄生虫的感染率在不同学校和年龄组之间存在差异，但在性别之间没有差异。除了钩虫感染率与曼氏血吸虫感染率之间存在强负相关外，不同感染在学校之间的感染率没有关系。在每个年龄组内，每种感染的分布几乎没有过多重叠；因此，多重感染的数量较低，而至少感染一种寄生虫的个体数量相对较高。感染蛔虫和曼氏血吸虫的儿童比预期的多，且聚集效应随年龄增加。只有2所学校的土源性蠕虫和血吸虫的总体感染率都很高。对发病率和寄生虫学数据的逻辑回归分析表明，与单一物种感染的个体相比，多重物种感染的个体发病风险（以乘法尺度衡量）并未增加。这部分归因于观察到的每种寄生虫的低虫卵计数。结果表明，在该地区，血吸虫感染和土源性蠕虫感染之间在寄生虫学方面以及它们对健康的综合影响方面几乎没有相互作用。讨论了土源性蠕虫和血吸虫联合防治的可行性和益处。
