Cao Zhi-Guo, Wang Tian-Ping, Zhang Shi-Qing, Yang Wei-Ping, Guo Jian-Duo, Zhao Feng, Sha Jian-Jun, Sun Wei-Bin, Hu Ping-An, Fang Guo-Ren, Zhu Lei
Anhui Institute of Schistosomiasis Control, Hefei 230061, China.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi. 2011 Dec;23(6):691-4.
To understand the dynamic changes of the potential prevalent factors of schistosomiasis in Chaohu Lake area so as to provide forecast information on the outbreak of schistosomiasis in the area.
From 2008 to 2010, fixed and mobile surveillance sites in potential endemic areas of Juchao District in Chaohu City, which was located in the southeast side of Chaohu Lake, were selected, and the schistosomiasis infection situation of local people, mobile population and livestock were investigated by immunological assays and/or stool examinations. The distribution of Oncomelania snails was surveyed in risk areas and suspicious areas, the spreading patterns of Oncomelania snails were observed in rivers that directly connected with the Yangtze River, and the Oncomelania snails were raised in the cages on the beaches of Chaohu Lake and a control area, and their survival and reproduction capacity was observed.
In 2008, a total of 301 local people were screened by IHA, and there were no positives. From 2008 to 2010, a total of 321, 362 and 306 mobile population were examined by IHA, respectively, and the positive rate of antibody were 3.74%, 4.97% and 2.94%, respectively. The antibody positives were tested by stool examinations, and the positive rates were 66.67%, 50% and 55.56%, respectively. A total of 91 local livestock and 92 livestock from endemic areas were examined respectively by the miracidium hatching method, and there were no positives. A total of 97.8 hm2 risk areas and 193.62 hm2 suspicious areas in the potential endemic area were surveyed respectively, but no Oncomelania snails were found. The investigation results on snail spreading patterns indicated that snails could spread into Chaohu Lake by adsorbing on floating debris. The field study revealed that Oncomelania snails could survive and reproduce in the Lake.
The imported infectious sources of schistosomiasis have been found in Chaohu Lake area, and the higher possibility of imported Oncomelania snails spreading into the Lake and surviving and reproducing in the lake is predicted. Therefore, effective measures should be taken to decrease the risks of schistosomiasis transmission in the potential endemic area.
了解巢湖地区血吸虫病潜在流行因素的动态变化，为该地区血吸虫病疫情预测提供信息。
2008 - 2010年，选取位于巢湖东南侧的巢湖市居巢区潜在流行区的固定和流动监测点，采用免疫学检测和/或粪便检查方法，调查当地居民、流动人口和家畜的血吸虫感染情况。在有螺区和可疑区域开展钉螺分布调查，观察与长江直接相连河流的钉螺扩散规律，并在巢湖及对照区滩地进行笼养钉螺，观察其生存繁殖能力。
2008年，共对301名当地居民进行间接血凝试验（IHA）筛查，无阳性。2008 - 2010年，分别对321、362和306名流动人口进行IHA检测，抗体阳性率分别为3.74%、4.97%和2.94%。对抗体阳性者进行粪便检查，阳性率分别为66.67%、50%和55.56%。分别采用毛蚴孵化法对91头当地家畜和92头疫区家畜进行检查，均无阳性。对潜在流行区内共97.8公顷有螺区和193.62公顷可疑区域进行调查，均未发现钉螺。钉螺扩散规律调查结果显示，钉螺可吸附于漂浮物扩散至巢湖。实地研究表明，钉螺可在巢湖生存繁殖。
巢湖地区已发现血吸虫病输入性传染源，预计存在外来钉螺传入巢湖并在湖内存活繁殖的较高可能性。因此，应采取有效措施降低潜在流行区血吸虫病传播风险。
