Kloos H, Higashi G I, Cattani J A, Schlinski V D, Mansour N S, Murrell K D
Soc Sci Med. 1983;17(9):545-62. doi: 10.1016/0277-9536(83)90297-6.
Preliminary findings of a study of the role of microspatial behavior and local ecological circumstances in the persistence of Schistosoma haematobium infection in El Ayaisha village, Upper Egypt, are presented. Twelve types of water contact activities were studied in three cohorts of 274,324 and 392 male students aged 5-16 during a 2-year period. Swimming and playing resulted in more frequent and intensive contact with potentially infective water and in more pollution of snail habitats with schistosome eggs than any other type of activity. Irrigation was probably not a major cause of S. haematobium infection in schoolboys and drinking water and fishing carried the smallest risk for this age group. Mapping and discriminate analysis of infection and transmission indicators revealed spatial associations between water contact, schistosome transmission and infection among the various age groups. The highest egg excretion rates in individuals and the highest prevalence rates were noted in the neighborhoods nearest to the canals. Water contact and contamination of water by the heavily infected school age boys is seasonally concentrated during the summer, when intermediate host snails and infective cercariae are also most common in the water. Frequency, type and duration of water contact change with age together with types of water bodies used, causing corresponding changes in exposure risk. Nevertheless, other factors, including acquired immunity, preexisting infections, chemotherapy and the effect of the study on the normal water contact behavior of the study population must also be evaluated. Contact with the Nile and the canals by the general nonschool population of El Ayaisha was studied to verify the observations among the schoolboys and to study socially linked activities and the transmission potential of the various transmission sites. Results are evaluated in regard to the feasibility of various schistosomiasis control measures in El Ayaisha.
本文介绍了一项关于微观空间行为和当地生态环境在埃及上埃及省艾亚沙村埃及血吸虫感染持续存在中作用的研究的初步结果。在两年时间里，对三个队列中年龄在5至16岁的274名、324名和392名男学生进行了研究，调查了12种与水接触的活动类型。与其他任何活动类型相比，游泳和玩耍导致与潜在感染性水的接触更频繁、更密集，并且使血吸虫卵对钉螺栖息地的污染更多。灌溉可能不是男学生感染埃及血吸虫的主要原因，而饮用水和捕鱼对这个年龄组的风险最小。对感染和传播指标进行绘图和判别分析，揭示了不同年龄组之间水接触、血吸虫传播和感染之间的空间关联。在离运河最近的社区中，个体的最高排虫卵率和最高患病率被记录下来。重度感染的学龄男孩的水接触和水污染在夏季季节性集中，此时中间宿主钉螺和感染性尾蚴在水中也最为常见。水接触的频率、类型和持续时间随年龄以及所使用水体的类型而变化，导致接触风险相应改变。然而，其他因素，包括获得性免疫、既往感染、化疗以及该研究对研究人群正常水接触行为的影响也必须进行评估。对艾亚沙村一般非在校人群与尼罗河和运河的接触进行了研究，以验证在男学生中观察到的情况，并研究社会关联活动以及各个传播地点的传播潜力。针对艾亚沙村各种血吸虫病控制措施的可行性对结果进行了评估。
