Haswell-Elkins M R, Elkins D B, Manjula K, Michael E, Anderson R M
Department of Pure and Applied Biology, Imperial College of Science and Technology, University of London.
Parasitology. 1987 Oct;95 ( Pt 2):339-54. doi: 10.1017/s0031182000057784.
The distribution and abundance of Enterobius vermicularis in a fishing community in South India, as determined by counting worms expelled following mass anthelmintic chemotherapy, was examined in samples of patients stratified by age, sex and family grouping. The results of a worm expulsion study in January 1984 are compared with those of a second expulsion programme in November 1984, following an 11-month period of reinfection. The prevalence of Enterobius infection was consistently high in all age groups of both males and females. A comparison of the overall prevalence and intensity of infection in the January and November surveys revealed significant increases in both the percent infected and the mean number of worms harboured in November relative to the initial level. No significant trends in the intensity of Enterobius according to host age or sex were detected in either survey. The frequency distribution of Enterobius was found to be highly aggregated in the population as a whole and within age groups. At both sampling dates, the most heavily infected 25% of the community harboured over 90% of the total pinworms recovered. There was a significant pattern within most age groups for individuals to re-acquire worm burdens of a similar magnitude to their initial pre-treatment burdens. Heavy infections were found to be associated with household. A selective or targetted approach to treatment of heavily infected individuals or households is likely to be an efficient means of reducing parasite abundance on a community-wide basis. It must be stressed, however, that treatment must be applied at frequent intervals in order to achieve a long-term reduction in pinworm abundance and to avoid the possibility of increasing the intensity of infection, as was observed in this community.
通过对大规模驱虫化疗后排出的蠕虫进行计数，确定了印度南部一个渔业社区中蠕形住肠线虫的分布和丰度，并在按年龄、性别和家庭分组的患者样本中进行了检查。将1984年1月驱虫研究的结果与1984年11月经过11个月再感染后的第二次驱虫计划的结果进行了比较。在所有年龄组的男性和女性中，蠕形住肠线虫感染率一直很高。1月和11月调查中总体感染率和感染强度的比较显示，相对于初始水平，11月感染百分比和平均携带蠕虫数量均显著增加。在任何一项调查中，均未发现按宿主年龄或性别划分的蠕形住肠线虫感染强度有显著趋势。发现蠕形住肠线虫在整个人口中以及各年龄组内的频率分布高度聚集。在两个采样日期，社区中感染最严重的25%的人携带了回收的全部蛲虫的90%以上。在大多数年龄组中，个体重新获得的蠕虫负担与其初始治疗前负担的大小相似，存在显著模式。发现重度感染与家庭有关。对重度感染的个体或家庭采取选择性或针对性的治疗方法，可能是在社区范围内降低寄生虫丰度的有效手段。然而，必须强调的是，为了实现蛲虫丰度的长期降低并避免感染强度增加的可能性，必须定期进行治疗，正如在这个社区中观察到的那样。
