输入性曼氏血吸虫病监测与防控对策专家共识

我国于20世纪80年代发现曼氏血吸虫中间宿主藁杆双脐螺进入广东深圳地区，目前已在深圳定殖并扩散至东莞、惠州等地区。鉴于输入性曼氏血吸虫病病例在我国时有报道，我国已经面临输入性曼氏血吸虫病在中国大陆传播的风险。随着我国进一步深化对外开放，特别是“一带一路”倡议的深入实施，曼氏血吸虫病在中国大陆的传播风险将逐渐增大。为防止曼氏血吸虫在我国形成完整生活史并造成疾病传播，提升对曼氏血吸虫病的认识、加强提前防控的意识以及尽早发现、报告、处置输入性曼氏血吸虫病病例或病原携带者尤为重要。国内多位传染病和寄生虫病防控专家就输入性曼氏血吸虫病监测与防控对策达成共识，旨在提升我国疾病预防控制机构和医疗机构关于输入性曼氏血吸虫病诊疗和防控意识与能力、降低甚至消除输入性曼氏血吸虫病在我国传播的风险，从根本上保障我国居民健康。     

输入性曼氏血吸虫病监测与防控对策专家共识

我国于20世纪80年代发现曼氏血吸虫中间宿主藁杆双脐螺进入广东深圳地区，目前已在深圳定殖并扩散至东莞、惠州等地区。鉴于输入性曼氏血吸虫病病例在我国时有报道，我国已经面临输入性曼氏血吸虫病在中国大陆传播的风险。随着我国进一步深化对外开放，特别是“一带一路”倡议的深入实施，曼氏血吸虫病在中国大陆的传播风险将逐渐增大。为防止曼氏血吸虫在我国形成完整生活史并造成疾病传播，提升对曼氏血吸虫病的认识、加强提前防控的意识以及尽早发现、报告、处置输入性曼氏血吸虫病病例或病原携带者尤为重要。国内多位传染病和寄生虫病防控专家就输入性曼氏血吸虫病监测与防控对策达成共识，旨在提升我国疾病预防控制机构和医疗机构关于输入性曼氏血吸虫病诊疗和防控意识与能力、降低甚至消除输入性曼氏血吸虫病在我国传播的风险，从根本上保障我国居民健康。     

巴西藁杆双脐螺对3株曼氏血吸虫的敏感性

人工湖等水利工程可能成为淡水螺的孳生地 ,增加人类及动物感染血吸虫的机会。作者在人工湖周围地区藁杆双脐螺的发生和分布的流行病学调查的基础上 ,研究了藁杆双脐螺对曼氏血吸虫毛蚴的敏感性。根据最近两年来螺的种群研究结果 ,选择湖区周围曼氏血吸虫病主要流行的地区进行调查。实验所需的 1 9个藁杆双脐螺种群中 ,大部分在流行区获得 ,另外两个对照种群来自于其它地区。螺分别暴露于 5个曼氏血吸虫毛蚴 (从 3株曼氏血吸虫分离获得 ,分别为CM、EC和PB株 )。观察感染的阳性率和尾蚴前期发育时间。暴露 6 0d后 ,尾蚴未逸出但仍然存活的…     

藁杆双脐螺密度和静水沉速的测定

目的了解曼氏血吸虫的中间宿主藁杆双脐螺的生态水力学特性。方法采用排水体积法和沉降管法分别测定了双脐螺的密度和静水沉速。结果藁杆双脐螺的密度在1.04~1.16 g/cm~3之间,平均密度为1.08 g/cm3;其静水沉速在2.32~12.92 cm/s之间。结论藁杆双脐螺的生态水力学特性与钉螺有所不同,在研究采用水利措施防控藁杆双脐螺扩散中应考虑其特性。     

非洲输入性血吸虫病在中国的传播风险及其应对措施

中国香港和深圳地区相继出现曼氏血吸虫中间宿主-藁杆双脐螺孳生地; 在我国援非项目和赴非务工人员数量剧增的同时, 赴非洲回国人员中感染曼氏或埃及血吸虫的报道亦逐渐增多; 在全球气候持续变暖的大环境下, 非洲血吸虫病会否在中国境内传播或流行, 再度引起了广泛关注。本文从生物学和流行病学角度, 就其传播风险作一剖析, 并提出相关应对措施。     

藁杆双脐螺昼夜活动的观察

藁杆双脐螺Biomphalarta straminea(Dunker1848)广泛分布于中美及南美洲,是曼氏血吸虫的中间宿主(Getz et al.,1975),而且是巴西东北部地区曼氏血吸虫最重要的中间宿主。Meier-Brook(1974)报告存香港发现此种双脐螺。作者在香港九龙新界地区的灌溉沟内也采到此螺。它们生活在水中,往往聚集成团,漂浮在水面或沉于水底。为了了解藁杆双脐螺的活动规律,在实验室内观察它在静水和充气水中的行为。     

塞内加尔Richard-Toll地区啮齿类动物作为曼氏血吸虫的保虫宿主

近年来曼氏血吸虫病在塞内加尔Richard-Toll地区爆发流行。该地区中间宿主浦氏双脐螺(Biomphalaria pfeifferi)的感染增多,啮齿类动物中亦有该病的广泛传播。因此,有必要对该地区野生啮齿类动物在曼氏血吸虫病传播中的作用作出评估。     

曼氏血吸虫在三种双脐螺中的发育

在巴西,曼氏血吸虫的中间宿主有B.tenagophila、藁杆双脐螺、光滑双脐螺三种双脐螺。本文比较研究了这三种螺的毛蚴感染水平及每天的尾蚴逸出数。 用实验室饲养的长度分别为8—10mm、8—10mm、4—7mm的上述三种双脐螺,进行曼氏血吸虫发育的比较研究。每种螺200只,     

巴西双脐螺的基因多样性及分子鉴定

在热带地区和非洲,双脐螺分布广泛并对线虫有很高的易感性,它们是曼氏血吸虫最重要的中间宿主。在巴西,现已经鉴定出双脐螺的10个种和一个亚种,它们分别是:光滑双脐螺(B.glabrata)、浅滩双脐螺(B.tenagophila)、藁杆双脐螺(B.straminea)、西方双脐螺(B.occidentalis)、奇异双脐螺     

阿曼南方血吸虫病地区媒介螺和病人的血清学鉴定

为进一步弄清阿曼南方地区曼氏血吸虫病和埃及血吸虫病流行情况及其媒介螺,作者在阿曼西南部佐法尔省的6个地区进行了现场调查。在取样的16个调查点中有15个点水体中都发现有密度不等的阿拉伯双脐螺(Biomphalaria arabica)。经实验观察,其中13个点的螺均有曼氏血吸虫尾蚴逸出,另2个点的螺逸出的为非血吸虫尾蚴。用自一个最大水体取得的78只阿拉伯双脐螺进行实     

Studies on common antigenicities between the Belo Horizonte strain, Brazil of Schistosoma mansoni eggs and Biomphalaria snails by immunoelectrophoresis.

Immunoelectrophoretic studies of common antigenicities were carried out by using rabbit sera immunized against the Belo Horizonte strain of Schistosoma mansoni eggs and crude antigens of Biomphalaria snails and vice versa. With regard to common antigenicities between S. mansoni eggs and Biomphalaria snails, S. mansoni eggs produced 4 to 5 bands with Biomphalaria glabrata pigmentado, 3 to 4 bands with B. glabrata albino and only 1 band with B. straminea. In our laboratory, the infection rate of S. mansoni miracidia to B. glabrata pigmentado was 64.3% and 55.0% for B. glabrata albino, but B. straminea was not found to be susceptible to S. mansoni miracidia. It was observe that more bands were seen between S. mansoni egg and suitable hosts. Biomphalaria snail crude antigens were fractionated by Sephadex G-100 column, and each fraction antigen was tested with anti-S. mansoni egg sera by immunoelectrophoresis. As results, three fractions were collected form each snail strains. The common antigenicities between fractionated antigens from Biomphalaria snails crude antigens and anti-S. mansoni egg sera mostly existed in the first fraction and they were estimated to have molecular weights over 45,000.     

Immunoelectrophoretic study on common antigens of S?o Louren?o da Mata and Belo Horizonte strains of Schistosoma mansoni adult worms and Biomphalaria snails.

Immunoelectrophoretic studies on common antigens were carried out by using rabbits sera immunized against S?o Louren?o da Mata and Belo Horizonte strains of Schistosoma mansoni adult worms and antigens of Biomphalaria glabrata pigmented (Jaboat?o--PE); B. glabrata albino (Belo Horizonte--MG) and B. straminea (S?o Louren?o da Mata, PE). Furthermore, the reverse approach was proceeded, namely, sera anti Biomphalaria snails produced in rabbits were tested against both strains of Schistosoma adult worm antigens. The analysis of the common antigens between the SLM strains of S. mansoni adult worm and B. glabrata pigmented showed 8 to 9 precipitin bands, 3 bands with B. glabrata albino and only 1 band with B. straminea crude extracts. On the other hand, the BH strain of S. mansoni adult worm antisera produced 6 to 7 bands with B. glabrata pigmented, 5 bands with B. glabrata albino and 1 band with B. straminea antigenic extract. Biomphalaria snails crude extracts were fractionated by Sephadex G-100 column and three fractions were collected from each snail strain. The fractions were tested with anti SLM and BH strains of S. mansoni adult worm sera by immunoelectrophoresis. The common antigens fractionated from Biomphalaria snails crude extracts and those found for both strains of S. mansoni adult worm mostly existed in the first fraction and they were estimated to have molecular weight over 158,000 daltons. In our laboratory, it was found a relationship between the antigenic similarities and experimental infection rates of S. mansoni towards Biomphalaria snails so that more bands were seen with increasing infection rates of S. mansoni.     

深圳大鹏半岛4种入侵医学贝类的发现

目的 目的 了解深圳大鹏半岛入侵螺类物种。 方法 方法 于2012年8月至2013年1月对深圳大鹏半岛进行软体动物 资源调查, 通过贝壳形态学观察等鉴定入侵螺种。 结果 结果 大鹏半岛境内发现4种入侵螺类, 均为医学贝类, 分别为褐云 玛瑙螺 （Achatina fulica）、 小管福寿螺 （Pomacea canaliculata）、 尖膀胱螺 （Physa acuta） 和藁杆双脐螺 （Biomphalaria stra? minea）。其中尖膀胱螺在全部采集地点均有发现, 褐云玛瑙螺和小管福寿螺在除杨梅坑外的调查点均有分布, 藁杆双脐 螺仅分布于大鹏镇。结论 结论 4种重要外来螺类在深圳大鹏半岛广泛入侵, 鉴于其在疾病传播和农业生产上具有的潜在 危害, 需加强预防控制     

Biological control of Biomphalaria glabrata and B. straminea by the competitor snail Thiara tuberculata in a transmission site of schistosomiasis in Martinique, French West Indies

In Martinique, intestinal schistosomiasis was discovered at the beginning of this century. The intermediate host snail, Biomphalaria glabrata, was considered in the past as a common species in the different habitats of the island, but during the last decade it has been found only in water-cress beds. Several of these water-cress cultures contained mixed populations of B. glabrata and B. straminea. Moreover, these habitats also constituted transmission sites for Schistosoma mansoni infection. In 1979 the thiarid snail Thiara ( = Melanoides) tuberculata was discovered in Madame river, Fort-de-France, and in the following years at other sites. In 1983 a programme of biological control using this snail was started in two groups of water-cress beds. In 1981-1982 the study site, Roxelane valley, sheltered important populations of B. glabrata (45-256 individuals/m2) and of B. straminea (2-30 ind./m2). In January 1983 the competitor T. tuberculata was introduced into the two groups of water-cress beds (1.3 and 1.7 ind./m2 respectively) and during subsequent years snail population sampling was carried out. The results showed rapid colonization by the competitor snail, whose densities reached 178 and 325 ind./m2 in November 1983 and a maximum of 9941 and 13,388 ind./m2 in October 1984. During that time, B. glabrata populations declined: 153 and 41 ind./m2 in November 1983, 4 and 0 ind./m2 in October 1984, and 0 ind./m2 in the two groups of water-cress beds in October 1985. A similar phenomenon was observed for B. straminea. Since October 1985 neither planorbid species has been found by exhaustive sampling of the habitats.(ABSTRACT TRUNCATED AT 250 WORDS)     

2013-2016年江苏省常州市螺情监测分析

目的 分析常州市2013-2016年钉螺分布和螺情变化情况,为制定防控措施提供科学依据。方法 收集2013-2016年常州市的螺情监测资料并进行统计分析。结果 2013-2016年常州市共查出有螺面积40.17 hm2,其中新发现有螺面积30.63 hm2。4年全市共解剖钉螺3 454只,未发现感染性钉螺。全市共查到有螺环境 51个,其中江湖滩、内陆、山丘类型的有螺面积分别为12.13（30.19%）、25.54（63.57%）、2.51 hm2（6.24%）。新发现有螺环境中,江湖滩、内陆类型的面积分别为8.00（26.12%）、22.63 hm2（73.88%）。有螺原因主要是外来输入和邻近扩散。4年药物灭螺面积共计71.74 hm2,巩固药物灭螺面积155.15 hm2,改造有螺环境面积15.90 hm2,改造历史有螺环境面积11.30 hm2。结论 内陆河道钉螺扩散是近年常州市新发螺情的关键,必须需加强监测和控制力度。     

Short report: Schistosoma mansoni miracidia are killed by the defense system of an Argentine strain of Biomphalaria straminea.

Biomphalaria straminea snails from Argentina fail to shed cercariae even if exposed to high doses of Schistosoma mansoni EC miracidia. Alternative explanations for this failure are that miracidia are unable to penetrate the snail's epithelium or that the miracidia are killed by the snail's defense system. To discriminate between these 2 possibilities, B. straminea snails were individually exposed to increasing doses of miracidia. Susceptible B. glabrata were used as controls. Exposed snails were fixed 12 hr after exposure, and histological sections of the whole specimens were examined. Miracidia were seen to penetrate the epithelium of B. straminea and B. glabrata at similar rates (14.7%), independent of the exposure level. Regardless of the miracidial dose, 94% of the penetrating miracidia appeared encapsulated by the B. straminea defense system, whereas in B. glabrata, only 42% of the miracidia underwent encapsulation. These results show that resistance of B. straminea to S. mansoni EC strain is due to an efficient defense system that destroys miracidia once they have penetrated.     

Susceptibility of Biomphalaria tenagophila and Biomphalaria straminea to Schistosoma mansoni infection detected by low stringency polymerase chain reaction

In order to determine Schistosoma mansoni infection rates in Biomphalaria tenagophila and B. straminea, low stringency polymerase chain reaction (LS-PCR) technique was used as a complementary method to light exposure technique. LS-PCR has already been standardized in our laboratory to detect the trematode DNA in B. glabrata. Higher S. mansoni infection rates were detected using conventional method and LS-PCR. The parasite DNA profile was detected in both species after 7-day exposure to miracidia, using LS-PCR. This technique enables early detection of schistosomiasis transmission focuses, in endemic areas, before the beginning of cercariae shedding.