Objective To understand the epidemiological characteristics of malaria and mosquito vector density in Dantu District of Zhenjiang City,so as to provide scientific evidence for the development of the malaria elimination strategy.Methods The data pertaining to the network reporting malaria epidemics,blood examinations of fever patients,indirect immunoinfluscent assays in primary school students,epidemiological investigations of malaria cases,foci investigation and treatment forms,and mosquito populations were collected in the malaria surveillance sites in Dantu District of Zhenjiang City from 2001 to 2016,and analyzed.Results A total of 16 malaria cases were detected in Dantu District of Zhenjiang City from 2001 to 2016,including 7 local cases,6 imported cases from other provinces of China,and 3 oversea-imported cases.During the study period,a total of 56 285 patients with fever received blood examinations,with a rate of 1.27％.Of the 51 709 local residents detected,5 cases were positive for the blood examinations,with a positive rate of 0.01％,and 8 out of the 4 576 mobile populations were positive for the blood examinations,with a positive rate of 0.17％.There was a significant difference detected in the positive rate of blood examinations between the local residents and mobile populations (P＜0.01).From 2001 to 2011,a total of 2 459 and 2 892 filter paper blood spots were collected from key populations and primary school students,and 31 (1.26％ positive rate) and 39 (1.35％ positive rate) were positive,with no significant difference seen in the positive rate of filter paper blood spots between key populations and primary school students (P＞0.05).A total of 1 744 mosquitoes were captured between 2001 and 2016,and all were identified as Anopheles sinensis.Conclusions No local malaria case has been detected in Dantu District of Zhenjiang City since 2008.However,in the presence of vectors transmitting malaria,there is a possibility of malaria transmission upon an importation of source of infection may cause.Further malaria surveillance and control is therefore required to consolidate the control achievements.

OBJECTIVE:To evaluate the effect and the benefits of the projects of water storage and aquaculture on Oncomelania hupensis snail control in the tidal flats wetlands of islet-beach type area of lower reaches of the Yangtze River.METHODS:The projects of water storage and aquaculture on 0. hupensis snail control were implemented in the tidal flats wetlands of islet-beach type of lower reaches of the Yangtze River. The breed situation of the snails was investigated by the conventional method before and after the project implementation and the effect of control and elimination of the snails by the projects were evaluated. At the same time, the cost-benefit analysis of two projects among them was performed by the static benefit-cost ratio method.RESULTS:All of 0. hupensis snails were eliminated in the first year after the implementation of seven water storage and aquaculture projects. The costs of detection and control of snails saved by each project was 69.20 thousand yuan a year on average. The annual net benefits of the "Nanhao Group 10 beach" project and "Wutao Group 6-14 beach" project were 2 039.40 thousand yuan and 955.00 thousand yuan respectively, and the annual net benefit-cost ratios were 1.09: 1 and 1.07: 1 respectively.CONCLUSION:The O. hupensis snails could be rapidly eliminated by the water storage and aquaculture, and the economic benefit is obvious, but the wetland ecological protection and flood control safety should be considered in the tidal flats wetlands of islet-beach type area of lower reaches of the Yangtze River.

目的 掌握镇江市丹徒区高桥镇安丰村土源性线虫病的流行动态和流行规律,为制订防制策略和措施提供依据.方法 采用改良加藤厚涂片法检查土源性线虫卵,3~12岁儿童加做透明胶纸肛拭法检查蛲虫卵.结果 五年来监测点内共监测5 304人,发现土源性线虫感染者17人,总感染率为0.32%.逐年的感染率分别为0.97%、0.29%、0.18%、0.09%和0.10%.虫种为蛔虫、钩虫、鞭虫,均为轻度感染.未发现蛲虫感染者.结论 监测点内土源性线虫感染率呈下降趋势,感染率水平处于低位,但监测区内的健康教育、改水改厕工作仍然需进一步加强.

Objective To understand the infectiion status of schistosome in water body of risk areas in order to early release the warnings and implement comprehensive measures to prevent the prevalence of acute schistosomiasis. Methods The data were collected on the endemic status of schistosomiasis in Dantu District of Zhenjiang City from 2006 to 2008, and 6 surveillance sites were determined at the focal waters distributed in the towns of Dantu area. Surveillance was performed over the snail infestation, water infectivity, prevalence of miracidia of Schistosoma japonicum in the focal water body from May to September between 2009 and 2010, and the positive were released in timely manner. Emergency measures were implemented, including intensive monitoring over the water infectivity, investigation on the status of snail infestation and its eradication as well as health education. Results Infested snails were free during the period of surveillance. A total of 1200 senti?nel mouse were distributed, and 1126 were recovered(93.83%), in which 13 were found positive(1.15%). Three sites were potentially infested, and one site was suspected in consecutive 2 surveillances in June and July of 2010. 5 500 sentinel snails in 6 000 were recovered(91.67%), in which 3 311 received detection by the cer?caria-shedding test, and showed no infections. Four times of warnings were released on the positive results. Screening examination of the 1 482 subjects contacted with the infested water by dipstick dye immunoassay (DDIA), positive results were found in 82(5.53%), and 7 were positive stools(0.47%). Seven in 169 herds of sheep were detected with infection(4.14%). A total of 15hm2 of water body within the monitoring sites were surveyed, where showed no snail infestation. Eradication of the snails and miracidia was performed respectively in 20hm2 and 11hm2 of water body. No single case of acute schistosomiasis occurred in two-year period of surveillance. Conclusion Surveillance over the water body of risk areas may effectively control the incidence of schistosomiasis endemic through early warning and emergency management.

江苏镇江市丹徒区曾是血吸虫病重疫区,全区通过20 余年的不懈防治,于1978 年达到血吸虫病控制标准.但从二十世纪80年代初期以来,血吸虫病疫情又呈现回升,是江苏省较重的血吸虫病流行区之一[1].丹徒区目前有近80%的有螺面积分布于江滩,江滩灭螺由于受经费、自然环境、长江洪水频发等多种因素的制约使局部地区钉螺难以彻底控制,造成江滩钉螺面积、阳性螺面积和疫情呈现回升趋势[2~4].为有效遏制螺情和疫情增长势头,我们于2006 年初选择高桥镇西滩,开展了综合治理控制血吸虫病传播的研究工作,并进行了5 年的效果观察,现将结果分析如下.

The surveillance of schistosomiasis in Sanzhou Village, a national schistosomiasis surveillance site, in Gaoqiao Town of Dantu District, Zhenjiang City from 2005 to 2009 showed that the schistosomiasis morbidity remained in a low level in the surveillance site; however, the Oncomelania snails and infected snail areas remained high. It is suggested that, in addition to snail control, comprehensive control measures should be strengthened, and the causes of infected snails in marshland should be investigated, so as to clarify the roles of various hosts in transmission of schistosomiasis.

Objective To investigate the effect of a suspension of niclosamide(SN) on cercariae of Schistosoma japonicum and effective concentrations of that suspension in order to provide scientific evidence for control strategies to prevent acute schistosomiasis.Methods SN was weighed and formulated into solutions with active concentrations of niclosamide of 1×10-5,0.5×10-5,1×10-6,0.5×10-6,1×10-7,and 0.5×10-7 ml/100 ml in the lab,and the effect of SN on cercariae was determined.Solutions with an active concentration of niclosamide of 1.2×10-5,1.2×10-6,1.2×10-7,1.2×10-8,1.2×10-0,and 1.2×10-10 were formulated.Cercariae were counted 0,10 and 30 min after 200 S.japonicum cercariae were transferred to the solutions and 30 min after mice were infected with the cercariae.Forty-five days after infection,the mice were dissected and the state of infection was observed.SN with a concentration of 0.02 g/m2 was sprayed for 1 h on the surface of water in the field,and then the infectivity of water was determined using sentinel mice.Results All cercariae were killed after coming into contact with an active concentration of niclosamide of more than 0.5×10-6 for 1 min,an active concentration of niclosamide of more than 0.5×10-7 for 2 min,or an active concentration of niclosamide of more than 1×10-8 for 30 min.However,all survived after coming into contact with an active concentration of niclosamide of less than 0.5×10-8 for under 60 min.After the cercariae came into contact with niclosamide of 1.2×10-5 for 10 or 30 min,the cercariae failed to infect mice.When the cercariae were exposed to niclosamide of 1.2×10-6 for 10 min,80% of mice were infected,and the worm burden of mice was 3.2 worms per mouse,but 30 min later the rate of infection in mice decreased to 0.Water in the field was infective,with a rate of infection in sentinel mice of 33.33%.After 0.02 g/m2 SN was sprayed on the water surface for 1 h,water failed to infect sentinel mice.Conclusion SN is toxic to S.japonicum cercariae and can be used to kill cercariae and prevent acute schistosome infections.

目的 评价25%氯硝柳胺乙醇胺盐悬浮剂(SCNE)的实验室和现场杀螺效果.方法 在实验室和现场采用SCNE浸杀、喷洒法灭螺,并与50%氯硝柳胺乙醇胺盐可湿性粉剂(WPN)、25%氯硝柳胺悬浮剂(SCN)进行效果比较.结果 室内浸杀:SCNE 24、48 h和72 h LC50值分别为0.058 3、0.044 2 mg/L和0.038 5 mg/L,SCN分别为0.047 4、0.041 2mg/L和0.041 2 mg/L,WPN分别为0.094 7、0.058 3 mg/L和0.044 2 mg/L,清水对照组钉螺死亡率均为0;室内喷洒:SCNE剂量为2、4、8 g/m2,用药3 d后钉螺死亡率均为100%,相应剂量组SCNE杀螺效果均高于WPN,与SCN相一致.现场浸杀:除1 g/m3浸杀钉螺1 d钉螺死亡率为93.33%外,SCNE 2、4、8 g/m3浸杀钉螺1、2、3 d钉螺死亡率均为100%;现场喷洒:SCNE剂量＞2 g/m2,用药3 d后钉螺死亡率均＞89%,相应剂量组SCNE杀螺效果均高于WPN.结论 SCNE具有较好的实验室和现场杀螺效果,为新型高效、使用方便的灭螺药物剂型.

Objective To understand the molluscicidal effect of spraying suspension concentrate of niclosamide (SCN) with low-water discharge and high concentrations in a laboratory and field. Methods SCN was made into solutions with high concentrations of 40.0,20.0,10.0,5.0,3.3,2.5 g/L and 2.0 g/L in the laboratory,and was used for molluscicidal experiments with different water discharges. SCN with effective contents of 0.5,1.0,2.0 g/m2 was used for molluscicidal experiments by spraying with different water discharges in the field. The experiments of niclosamide ethanolamine salt 50% wettable powder (WPN) and fresh water were performed as the control. The molluscicidal effects after the spraying for 3,7,15 d were observed. Results The mortality rates of snails by using spraying 2 g/m2 SCN (effective content: 0.5 g/m2) for 3,7,15 d were 86%-100% with different water discharges,94%-100% by using spraying 4 g/m2 SCN (effective content: 1.0 g/m2) and 98%-100% by using spraying 8 g/m2 SCN (effective content: 2.0 g/m2) in the laboratory. The mortality rates of snails by using spraying SCN with effective contents of 0.5,1.0,2.0 g/m2 for 3,7,15 d were 86.08%-98.30% with different water discharges in the field. It was indicated that,with the decline of water discharges,the molluscicidal effects of SCN did not decrease significantly. However,the molluscicidal effects of WPN decreased remarkably,there was a significant difference between SCN and WPN (P<0.05). The mortality rates of snails by using SCN were all higher than those by using WPN both in the laboratory and field. The mortality rate of snails by using SCN with the effective content of 0.5 g/m2 was similar to that of WPN with the effective content of 1.0 g/m2,and the mortality rate of SCN with the effective content of 1.0 g/m2 was similar to that of WPN with the effective content of 2.0 g/m2 in the laboratory. Conclusions SCN,spraying with low-water discharge and high concentrations,can not only reduce water discharge,but also gain a good molluscicidal effect and save the cost. It is suitable for snail control in lacking water areas and areas far from water sources.

镇江市丹徒区地处长江下游,是江苏省血吸虫病流行相对较严重的地区之一,2005年丹徒区高桥镇三洲村被列为全国血吸虫病监测点[1].为及时了解血吸虫病流行动态和规律,为制订血吸虫病防治策略措施和评价防治效果提供科学依据,2007年我们继续按照<全国血吸虫病监测方案>的要求,开展并完成了各项监测任务.现将疫情监测结果报告如下.

目的 探讨镇江市丹徒区陈丰山区感染性钉螺形成原因及其防治对策,为制定山丘地区血吸虫病防治策略提供科学依据.方法 2006、2007年对陈丰山区的有螺环境进行螺情调查,对调查区内的居民、附近的流动人口及家畜进行病情调查,并对调查区内野生动物保虫宿主感染情况进行调查,同时在调查区内采取灭螺、化疗、健康教育等综合性防治措施.结果 2年调查区内共查出有螺面积7.5 hm2,感染性钉螺面积6.0 hm2;常住人口胶体染料试纸条法(DDIA)血检阳性率1.93%,未发现粪检阳性病人,流动人口DDIA阳性率0.05%,粪检阳性1人;查出阳性耕牛2头;对29份野粪进行粪检,共发现阳性4份,均为牛粪;对13只野生动物保虫宿主解剖,均未发现阳性.2年血吸虫病防治措施落实良好.结论 耕牛为该地区阳性钉螺形成的重要原因之一.调查区内采取的综合性防治措施取得了一些效果,但该地区的灭螺、流动人口血吸虫病防治及健康教育仍不容忽视.

<正>为及时了解血吸虫病流行动态和流行规律及制订血吸虫病防治策略措施和评价防治效果提供科学依据,江苏省镇江市丹徒区高桥镇三洲村于2005年被列为全国血吸虫病监测点[1]。我们在总结

<正>镇江市丹徒区地处长江中下游,是江苏省血吸虫病流行较严重的地区之一,为掌握血吸虫病流行动态和流行规律,2005年高桥镇三洲村被列为全国血吸虫病疫情监测点。按照《全国血吸虫病监测方案》要求,现将2005年三洲村疫情监测结果报告如下。

镇江市丹徒区是血吸虫病流行较严重的地区,全区有螺面积及感染性钉螺面积90%分布在未治理的江滩.多年来由于灭螺经费投入不足和长江洪水频发等多种因素的影响,灭螺效果难以控制和巩固[1].从2001年起,我们对世业镇北滩进行了综合治理,并进行了5年的效果观察.

目的了解江苏省镇江市丹徒区中小学生血吸虫感染现状.方法对丹徒区中小学生采用胶体染料试纸条法(DDIA)进行血清流行病学调查.结果丹徒区有中小学生48 437人,受检45 169人,受检率为93.25%;DDIA检测阳性549人,阳性率1.22%.男性的DDIA阳性率高于女性(x2=146.70,P＜0.01);未控制地区DDIA阳性率高于传播阻断地区(x2=313.88,P＜0.01);未控制地区6～12岁DDIA阳性率逐渐增加,12岁达最高,13～18岁逐渐下降;相邻年龄组DDIA检测结果显示,7岁与8岁组差异有显著性(x2=4.50,P＜0.05),12岁与13岁组差异有显著性(x2=4.96,P＜0.05),16岁与17岁组差异有显著性(x2=10.75,P＜0.01).结论小学生随年龄增加DDIA阳性率逐渐上升至12岁达高峰,13岁后(进入中学)DDIA阳性率下降,故加强小学生的血防健康教育尤其重要.

目的掌握镇江市丹徒区世业镇新滩村疫情监测点建立5年来的疫情变化情况.方法按<全国血吸虫病疫情监测方案>的方法,每年开展螺情、病情等纵向观察.结果通过5年的疫情监测显示监测区内螺情形势严峻,病情持续稳定在较低水平.结论监测区采取的综合性防治措施在病情控制上有一定成效,但仍需加强江滩的综合治理和传染源的监测.

氯硝柳胺悬浮剂是江苏省血吸虫病防治研究所新研制的一种氯硝柳胺新剂型.试验表明,其杀螺效果高于氯硝柳胺乙醇胺盐可湿性粉剂,且易溶于水,使用方便[1].