江滩工业开发阻断血吸虫病传播措施及其效果评价

Industrial development-based interventions and effectiveness for interrupting schistosomiasis transmission in marshland regions

目的评价江滩型流行区实施江滩工业开发为主措施阻断血吸虫病传播的效果,为江滩地区阻断和消除血吸虫病提供有效对策。方法采用前瞻性现场研究的方法,选择一个江滩型血吸虫病流行区县,对圩外江滩环境实施以工业开发为主的综合治理。连续开展居民病情、家畜病情和环境螺情调查,并收集综合开发措施实施情况。分析比较实施综合开发前后血吸虫病疫情变化状况,综合评价阻断血吸虫病传播的效果。结果 2001-2015年项目区共开发江滩面积496.34hm^2,占江滩总面积的90.16%。其中,工业开发江滩面积411.80hm^2,占74.81%;农业开发江滩面积84.55hm^2,占15.36%。共对6条通江河道进行混凝土护坡4.87km,改造涵闸与建造沉螺池9座。实施工业开发为主措施后,项目区钉螺和感染性钉螺面积呈快速下降态势,2001-2007年钉螺面积下降了80.55%,年均下降13.43%,到2012年消灭了钉螺;2002-2005年查出感染性钉螺面积占97.92%(50.29/51.36),到2007年消灭了感染性钉螺。2001-2004年(开发初期)查出病人占总数的88.77%(245/276),居民感染率在0.14%-0.51%之间,期间发生急性感染病人122例;2005-2011年(开发中期)查出病人占总数的11.23%(31/276),居民感染率在0.01%~0.03%之间;2012-2015年(开发后期)未查到粪阳病人,居民感染率已降为0。15年间仅在开发前期的2003年查到粪检阳性家畜13头,当年家畜感染率为1.32%。结论江滩地区实施沿江工业开发是阻断血吸虫病传播与促进当地经济发展的共赢之策,但在实施工业开发的前期要重点加强人群感染防护,并加强家畜放牧管理,防止突发疫情的发生。

Objective To evaluate the effectiveness with which industrial development based interventions interrupt the transmission of schistosomiasis in marshland regions in order to formulate effective strategies for interruption of schistoso- miasis transmission and schistosomiasis elimination in marshland regions. Methods A prospective field study was de- signed. A marshland region where schistosomiasis is endemic was selected, and industrial development-based comprehen-sive control was implemented outside that region. The schistosomiasis morbidity in humans and livestock and snail survey were continuously performed, and the implementation of the comprehensive control interventions was investigated. Chan ges in the prevalence of schistosomiasis were compared before and after the implementation of industrial development- based comprehensive control to evaluate the effectiveness with which the transmission of schistosomiasis was interrupted. Results From 2001 to 2015, a total of 496.34 hm^2 of marshland was reclaimed in the studied region, accounting for 90.16% of the total marshland area. A total of 411.80 hm^2 of former marshland （74.81%） was used for industrial development and 84.55 hm^2 of former marshland （15.36%） was used for agricultural development. Concrete revetments were constructed on the banks of 6 tributaries to the Yangtze River, and 9 sluices/settling basins for snails were modified or built. After the implementation of industrial development-based comprehensive control, a dramatic decline in the area of snail habitats and areas with infected snails was observed, and the area of snail habitats decreased by 80.55% in 2007 relative to the area in 2001, with an annual decrease of 13.43%. All snails were eliminated in 2012. In 2007, infected snails had been eliminated from 97.92 % （50.29 hm^2/51.36 hm^2） of the area where infected snails were detected between 2002 and 2005. Eighty-eight-point-seventy-seven percent （245/276） of patients with schistosomiasis were detected in the early stage of development （2001 to 2004）, and 122 cases of acute schistosomiasis were noted. The rate of human infection ranged from 0.14% to 0.51%. Eleven-point-twenty-three percent （31/276） of patients with schistosomiasis were detec- ted in the middle stage of development （2005 to 2011）, and the rate of human infection ranged from 0.01% to 0.03%. No patients with schistosomiasis were detected in the late stage of development （2012 to 2015）, and the rate of human infection decreased to 0 %. During the 15 years of development, only 13 heads of infected livestock were detected in 2003, with an infection rate of 1.32% in 2003. Conclusion Industrial development is a win-win strategy to interrupt schisto- somiasis transmission and promote local economic development in marshland regions; however, schistosomiasis control and management of livestock grazing need to be enhanced to prevent sudden outbreaks.snail habitats and areas with infected snails was observed, and the area of snail habitats decreased by 80.55% in 2007 relative to the area in 2001, with an annual decrease of 13.43%. All snails were eliminated in 2012. In 2007, infected snails had been eliminated from 97.92 % （50.29 hm^2/51.36 hm^2） of the area where infected snails were detected between 2002 and 2005. Eighty-eight-point-seventy-seven percent （245/276） of patients with schistosomiasis were detected in the early stage of development （2001 to 2004）, and 122 cases of acute schistosomiasis were noted. The rate of human infection ranged from 0.14% to 0.51%. Eleven-point-twenty-three percent （31/276） of patients with schistosomiasis were detected in the middle stage of development （2005 to 2011）, and the rate of human infection ranged from 0.01% to 0.03%. No patients with schistosomiasis were detected in the late stage of development （2012 to 2015）, and the rate of human infection decreased to 0 %. During the 15 years of development, only 13 heads of infected livestock were detected in 2003, with an infection rate of 1.32% in 2003. Conclusion Industrial development is a win-win strategy to interrupt schisto- somiasis transmission and promote local economic development in marshland regions; however, schistosomiasis control and management of livestock grazing need to be enhanced to prevent sudden outbreaks.