炼铁山区血吸虫病流行病学调查

EPIDEMIOLOGICAL SURVEY OF SCHISTOSOMIASIS IN HIGH MOUNTAINOUS REGION IN ERYUAN COUNTY OF YUNNAN PROVINCE

炼铁镇的居民及耕作均在山坡上,海拨在1,700～2,300m之间。居民血吸虫感染率平均为53.6％,以16～30岁人群最高,女性高于男性;在8种动物中发现有血吸虫感染,其中牛在传播血吸虫病方面特别重要。人,畜野粪污染水体较为普遍。钉螺按水系呈割裂状分布,孳生环境复杂多样,钉螺感染率平均为1.2％钉螺及感染螺以梯田埂为多,其次为田间、小沟及渗水荒田、草地。感染螺在村周150m以内占50％。有些远离村庄1km外的环境也较多。血吸虫病疫情轻重同海拔高低无明显关系,但同地理条件关系密切。居民感染血吸虫主要季节为6～9月,感染集中场所是梯田耕作区,感染方式主要与种植水稻有关的生产活动。

The epidemic area of Liantie high mountainous region of Eryuan County is situated on the western hillside of Laoping mountain, 1,700~2,300 meters above sea level. The infection rate of schistosomiasis japonica was 53.6% in persons examined in 10 villages but was 70.4% among the 16~30 age group, and the majority were women. The animal hosts were catties, buffaloes, pigs, dogs, horses, goats and rats, and the catties played an important role in the transmission of the disease. Faeces of human and domestic animals scattered in the area where the snail intermediate host were widely distributed. The average infection rate of Oncomelania snails was 1.2%.The infected snails dispersed mainly over the banks of earth between terraced fields, small ditches and hillside with seeping waters. Epidemic level of schistosomiasis was concerned with river systems and geographical conditions, but it was independent of height above sea level in the area.The most importent infective season was from June to August and the infective sites were working areas of terraces. The results obtained showed that the epidemiological charecteristics of schistosomiasis in high mountainous regions were different from that of the plain.