鄂西北斯氏并殖吸虫第二中间宿主自然感染情况的监测

Results of monitoring of the natural infection rate of second intermediate host of Paragonimus skrjabini in northwestern Hubei

目的调查斯氏并殖吸虫第二中间宿主孳生环境及自然感染情况的变化并对其影响因素进行分析。方法调查收集部分县(市)斯氏并殖吸虫自然疫源地中间宿主溪蟹及动物宿主自然感染情况,观察和分析人类行为、局部环境的改变对中间宿主孳生、感染的影响。结果调查显示环境因素、人类行为对斯氏并殖吸虫疫源地、第二中间宿主溪蟹孳生和囊蚴自然感染有明显的影响,平均感染率由1985～1995年的17.08%降为1996～2007年的5.96%。结论生态环境改变和人类的行为直接影响了野生动物的活动范围及中间宿主的孳生,导致中间宿主囊蚴的感染率逐渐降低。但随着退耕还林实施,生态环境的改善,有利于中间宿主螺和溪蟹的孳生和繁殖,可能形成新的疫源地。溪流中蟹类肺吸虫囊蚴感染可能随之加重,人群感染肺吸虫的机会也可能随之增加。

Aim To investigate the breeding environment and changes in natural infection rate of Paragonimus skrjabini, the second intermediate host. Methods The data of the natural infection rate of crab of the intermediate host crab and animal host in infectious foci of Paragonimus skrjabini were collected and analyzed. Results The impact of environment factors,human behavior on the pagomgonimus foci,the second intermediate hosts and river crabs breeding naturally infected with metacercaria was significant,the average infection rate dropped from 17.08% in 1985 to 5.96%in 1996 and 2007. Conclusion Eco-environmental change and human behavior directly affect the range and breeding of wild animals and the intermediate host,resulting in the decrease of infekction rate of metacercariae gradually. However,with the implementation of returning farmland to forest,improvement of the ecological environment is conducive to the breeding of snail intermediate hosts and river crab,there might appear new infectious foci. Thus paragonimiasis would be prevalent in this area.