Schistosomiasis is a neglected tropical disease that severely threatens human health and affects the socioeconomic development. The causative agent that parasitizes in humans mainly involves Schistosoma japonicum,S. mansoni,S. haematobi-um,S. intercalatum and S. mekongi. As the firstly identified schistosome,S. haematobium infection is found to strongly correlate with bladder cancer. This paper mainly reviews the discovery,morphology and life cycle of S. haematobium.

A total of 13 allozymes of 7 populations of Oncomelania snails trom 7 provinces in the mainland China were examined by horizontal starch gel electrophoresis. Results demonstrated that out of 17 loci examined, 10 were monomorphic loci: Aldh,Ao,G6pd ,Gpdh,Hbdh,Ldh, Sdh,Est-2,Est-3,and Est-6,and 7 were polymorphic loci:Est-4,Est-5,Xdh,Mdh,Idh,Got and Ap. Banding pattern showed that six enzymes were polymorphic accounting for 46.15 % (6/13) of total enzyme systems examined. Results indicated that a certain of relative relation-ship was existed along with the significant variation presented based on their environment and location among the 7 populations of snails from the mainland of China. It was revealed that the 7 polymorphic loci were the important loci affecting the gentic variation in the differ-ent populations of Oncomelania spp.

Objective To evaluate the outcomes of implementation of integrated schistosomiasis control strategy with empha? sis on infectious source control using a bibliometric method. Methods The literature pertaining to integrated schistosomiasis control strategy with emphasis on infectious source control was retrieved from CNKI,Wanfangdata,VIP,PubMed,Web of Sci? ence,BIOSIS and Google Scholar,and a bibliometric analysis of literature captured was performed. Results During the period from January 1,2004 through September 30,2014,a total of 94 publications regarding integrated schistosomiasis control strate? gy with emphasis on infectious source control were captured,including 78 Chinese articles(82.98%)and 16 English papers (17.02%). The Chinese literature was published in 21 national journals,and Chinese Journal of Schistosomiasis Control had the largest number of publications,consisting of 37.23% of total publications;16 English papers were published in 12 interna? tional journals,and PLoS Neglected Tropical Diseases had the largest number of publications(3 publications). There were 37 affiliations publishing these 94 articles,and National Institute of Parasitic Diseases,Chinese Center for Disease Control and Pre? vention(16 publications),Anhui Institute of Schistosomiasis Control(12 publications)and Hunan Institute of Schistosomiasis Control(9 publications)ranked top three affiliations in number of publications. A total of 157 persons were co?authored in these 94 publications,and Wang,Zhou and Zhang ranked top 3 authors in number of publications. Conclusion The integrated schistosomiasis control strategy with emphasis on infectious source control has been widely implemented in China,and the achievements obtained from the implementation of this strategy should be summarized and transmitted internationally.

The surveillance of schistosomiasis in Sanzhou Village, Dantu District, Zhenjiang City, a national schistosomiasis surveillance site, showed that in 2008, the area with snails was 27 hm~2, among which the area with infected snails was 14 hm~2, the densities of living snails and infected snails were 0. 86 and 0.002 1 snails/0. 1 m~2, respectively. The infection rate of snails was 0.25% , the positive rate of IHA was 3. 10% and the infection rate of schistosome in human populations was 1%. There were no infected domestic animals found, and there were no acute schistosomiasis and newly advanced schistosomiasis cases found in the surveillance site in 2008. It is indicated that the endemic situation of schistosomiasis is stable. The comprehensive control, including molluciciding and environmental modification, should be implemented for snail control. The comprehensive measures with emphasis on infectious source control should be further strengthened.

Oncomelania hupensis is the only intermediate host of Schistosoma japonicum. The elimination of Oncomelania snails is the key technique step for schistosomiasis control. This paper summarizes the progress of the techniques of snail control，including the methods of ecology engineering，biology，molluscicides and the study on novel molluscicides，and reviews their features. In addition，this paper explores the appropriate approach to control the snails.

Objective To evaluate the impact of the project diverting the Yangtze River water to the Northern Jiangsu on transmission towards the north of Oncomelania hupensis snails, in order to provide the scientific basis for the South-North Water Diversion Project (east route). Methods The running situation of the water diversion project, the data on hydrology of the waterway and the distribution of snails and schistosomiasis were investigated with the methods of epidemiology、hydrology and field test. Results There was no significant correlation between the region of waterhead and water supply on the change of snail areas. There was no significant correlation between the snail areas of the region of water supply and the volume of water diversion, either. The snail habitat was stable at the Gaoyou segment along the Grand Canal. The snail habitat in the natural place of the north of 33?15′ north latitude on the east route has not been discovered yet. Conclusion There is no sign of transmission towards north on the snail habitat at the Gaoyou segment along the Grand Canal since the project was constructed in 1961. There is no evidence that the project leads to the spread of snails and schistosomiasis, either.

The genetic divergence between geographically separated populations can be studied by comparing the divergences in their allele frequencies to the geographical distance of popula-tions. The present study is to examine the divergences in allele frequencies and genetic diver-gence in relation to the geogrephical distance of the samples localities, in order to test the population structure model of Oncomelania from the endemic areas in mainland China.The results showed that three patterns of allele frequency distributions occured in seven polymorphic loci, which were even,chaotic and discontinuous cline distributions. The distcon-tinuous or stepped clines shown in loci Est-4,Got and Mdh-2 suggested that the discrete subpopuation model is the likeliest. The plot of genetic distance (Nei's 1978) between sample populations against the geographic distances suggested that the special pattern of allele fre-quency distribution could be found. The regression analysis shows that logistic sigmoid re-gression is the best model to fit the original data in the plot. This supports the existence of the discrete subpopulations model in the population structure studied.

Objective To identify the trend of endemic situation among surveillance sites in Jiagsu Province from 2000 to 2002. Methods Twelve schistosomiasis surveillance sites were es-tablished ,and the longitudinal, surveillance was carried out. Results The related index of snail increased in most of surveillance sites, the rates of positive snails rose rapidly in marshlands. The infection rates of Schitosoma janponicum of cattle decreased and infection rates of human were relatively steady. However, there was still the danger of heavy endemic. Conclusion Current control strategies can not effectively adapt to the endemic situation of schistosomiasis, although which have some effects on control of morbidity. We need to study the new characteristics and rule of the endemic of schistosomiasis, and make out more effective control strategies which can suit with the current society, economies and nature environment.

Objective To evaluate the eff ec t of snail control with niclosamide ethanolamine salt dustable powder (DP) in th e marshland of the Yangtze River ahead of the schedule in spring, and to underst and the impact of the low temperature to molluscicidal effect of the dusting. Methods The snail control test with niclosamide ethanolamine salt dustable powder was carried out under different te mperatures in laboratory. Then the snail control was undertaken in the marshland of the Yangtze River ahead of the schedule in spring, and the molluscicidal ef fect was observed and the temperature changes were also considered. Results When the temperature was 15 ℃ and 25 ℃ respectively, there was no significant difference on the molluscicidal effec t of niclosamide ethanolamine salt DP in laboratory. The average atmosphere temp erature in each day was 8.9-16.3 ℃ from the last ten-day of March to the fir st ten-day of April in Nanjing regions. The corrected mortality of snails and the r educed rates of density of snails were 95.38% and 99.97% respectively on the s ur face of the soil in the marshland field. The corrected mortality and the reduced rates of density of snails were 79.30% and 70.59% respectively in the surface l ayer of the soil. Conclusion The impact of air t emperature is little to the molluscicidal effect of niclosamide ethanolamine sal t DP when the average atmosphere temperature in each day was 10-15 ℃ in the ma r shland of the Yangtze River. If the snail control is undertaken ahead of the sch edule in spring, the reproduction of snails will be suppressed and the infection of Schistosma japonicum will be controlled. [

Objective To determine the de ve lopmental zero and effective accumulated temperature of Oncomela nia eggs under con stant temperature. Methods The eggs were cultur ed under different constant temperature, and their development duration and effe ctive accumulated temperature were studied. The zero accumulated temperature (℃ ) was obtained by using an estimation mode, and the effective accumulated temp erature was obtained by effective accumulated mode of K=N(T-C). [WT5”H Z] Results The average development duration was (27.29?17 .2 9) d under 15-30 ℃, the development zero temperature was 11.79 ℃ and 38.22 ℃ u nder low and high temperature respectively, and the average development temperat ure and effective accumulated temperature were (557.76?198.95) DD and(236 .02 ?68.20) DD.Conclusion The suitable developme nt temperature of eggs is 27 ℃, the development speed and effective accumulated t e mperature of eggs increases with the temperature under given condition, but too high temperature may have negative impact on the development of eggs. The resul t can be considered as the basic biological parameter of the snail.