Chu K Y, Dawood I K
Bull World Health Organ. 1970;42(4):575-80.
The cercarial transmission seasons of Schistosoma mansoni in the Nile Delta area were determined by 3 methods: (1) monthly cercarial infection rates in Biomphalaria alexandrina, (2) monthly numbers of infected snails collected by means of a uniform sampling method, and (3) monthly cercarial output and monthly numbers of infected snails collected by means of a uniform sampling method. It was found that the third method is more logical and defines more precisely the transmission seasons of S. mansoni in the area. The paper also includes a discussion on the important factors that influence the timing of mollusciciding operations for the control of schistosomiasis in the Nile Delta area.
采用3种方法确定了尼罗河三角洲地区曼氏血吸虫尾蚴的传播季节：（1）亚历山大双脐螺的月度尾蚴感染率；（2）通过统一抽样方法收集的每月感染螺数量；（3）每月尾蚴产出量以及通过统一抽样方法收集的每月感染螺数量。结果发现，第三种方法更具逻辑性，能更精确地界定该地区曼氏血吸虫的传播季节。本文还讨论了影响尼罗河三角洲地区控制血吸虫病灭螺作业时机的重要因素。
