Comparison of pathogenicity and gene expression profiles between adult Schistosoma japonicum isolated from hilly and marshland and lake regions of Anhui Province / 中国血吸虫病防治杂志

Objective To compare the differences in pathogenicity and gene expression profiles between adult Schistosoma japonicum isolated from hilly and marshland and lake regions of Anhui Province, so as to provide the scientific evidence for formulating the precise schistosomiasis control strategy in different endemic foci. Methods C57BL/6 mice were infected with cercariae of S. japonicum isolates from Shitai County (hilly regions) and Susong County (marshland and lake regions) of Anhui Province in 2021, and all mice were sacrificed 44 days post-infection and dissected. The worm burdens, number of S. japonicum eggs deposited in the liver, and the area of egg granulomas in the liver were measured to compare the difference in the pathogenicity between the two isolates. In addition, female and male adult S. japonicum worms were collected and subjected to transcriptome sequencing, and the gene expression profiles were compared between Shitai and Susong isolates of S. japonicum. The differentially expressed genes (DEGs) were subjected to Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. Results The total worm burdens [(14.50 ± 3.96) worms/mouse vs. (16.10 ± 3.78) worms/mouse; t = 0.877, P = 0.392], number of female and male paired worms [(4.50 ± 0.67) worms/mouse vs. (5.10 ± 1.45) worms/mouse; t = 1.129, P = 0.280], number of unpaired male worms [(5.50 ± 4.01) worms/mouse vs. (5.60 ± 1.69) worms/mouse; t = 0.069, P = 0.946], number of eggs deposited in per gram liver [(12 116.70 ± 6 508.83) eggs vs. (16 696.70 ± 4 571.56) eggs; t = 1.821, P = 0.085], and area of a single egg granuloma in the liver [(74 359.40 ± 11 766.34) µm2 vs. (74 836.90 ± 13 086.12) µm2; t = 0.081, P = 0.936] were comparable between Shitai and Susong isolates of S. japonicum. Transcriptome sequencing identified 584 DEGs between adult female worms and 1 598 DEGs between adult male worms of Shitai and Susong isolates of S. japonicum. GO enrichment analysis showed that the DEGs between female adults were predominantly enriched in biological processes of stimulus response, cytotoxicity, multiple cell biological processes, metabolic processes, cellular processes and signaling pathways, cellular components of cell, organelles and cell membranes and molecular functions of binding and catalytic ability, and KEGG enrichment analysis showed that these DEGs were significantly enriched in pathways of vascular endothelial growth factor signaling, glutathione metabolism, arginine and proline metabolism. In addition, the DEGs between male adults were predominantly enriched in biological processes of signaling transduction, multiple cell biological processes, regulation of biological processes, metabolic processes, development processes and stimulus responses, cellular components of extracellular matrix and cell junction and molecular functions of binding and catalytic ability, and these DEGs were significantly enriched in pathways of Wnt signaling, Ras signaling, natural killer cells-mediated cytotoxicity, extracellular matrix-receptor interactions and arginine biosynthesis. Conclusions There is no significant difference in the pathogenicity between S. japonicum isolates from hilly and marshland and lake regions of Anhui Province; however, the gene expression profiles vary significantly between S. japonicum isolates.

Spatiotemporal distribution of oncomelania hupensis snail habitats in the Middle and Lower Reaches of the Yangtze River / 公共卫生与预防医学

Schistosomiasis is one of the major communicable diseases, which seriously impacts human health, Oncomelania hupensis snail is unique intermediate host of Schistosoma japonicum as well as posts significant influence on schistosomiasis transmission. The long-term serial data of oncomelania snail area in the Middle and Lower Reaches of the Yangtze River in the Schistosomiasis situation in People's Republic of China ,were collected from 1999 to 2018. The spatial and temporal variation characteristics of oncomelania hupensis area in five provinces were analyzed by Manner-Kendall test. In the spatial change, the area composition ratio of lake-and-marshland regions in Hunan increased, while that in Hubei and Jiangxi showed a slight decline. The lake-and-marshland snails in Anhui showed a significant downward trend, while Jiangsu showed no stable trend. In the spatial change, the area of lake-and-marshland snails in Jiangsu, Anhui, and Hubei showed a downward trend, among which the downward trend in Hubei was not obvious, while the upward trend in Jiangxi and Hunan had an upward trend but the trend was not obvious. the year of the sudden change in the area of the lake and marshes in in Jiangsu and Hubei were 2010 and 2017 ; There was no significant mutation in Anhui Province; the mutation point of the lake-and-marshland snails in Hunan was between 2001 and 2002; the mutation year of the lake-and-marshland snails in Jiangxi was 2002.This paper studies the temporal and spatial changes of the snail breeding area in the middle and lower Yangtze River, and the results can provide a basis for the elimination of snails in different types of distribution areas.

Impact of water body environments on the microbial community of Oncomelania hupensis snails in marshlands around the eastern Dongting Lake / 中国血吸虫病防治杂志

Objective To evaluate the effects of water body environments on the microbial community of Oncomelania hupensis snails in marshlands of the eastern Dongting Lake where natural extinction of O. hupensis snails are found, so as to explore the correlation between the natural extinction of O. hupensis snails and the microbial community in snails. Methods Snails were caged water bodies in the Qianliang Lake marshland (Qianliang Lake regions) where natural extinction of snails was found and in the Junshan Park marshland (Junshan Park regions) in the eastern Dongting Lake for 30 days, and then all snails were collected and identified for survival or death. DNA sequencing of the fungi and bacteria was performed in snails before and after immersion in waters, and the biodiversity and abundance were analyzed. Results The survival rates of O. hupensis snails were 28.0% (70/250) and 64.8% (162/250) in Qianliang Lake regions and Junshan Park regions 30 days after immersion in waters, respectively (χ2 = 81.365, P < 0.01). The number of the fungal community and the biodiversity of the bacterial community were both greater in snails caged in Qianliang Lake regions post-immersion than pre-immersion, and there was a significant difference in the structure of the fungal and bacterial communities. The microbial community with a significant difference included Flavobacteriaceae,which was harmful to O. hupensis snails. Conclusion The water body environment affects the composition of the microbial community in O. hupensis snails in marshlands with natural snail distinction around the eastern Dongting Lake; however, further studies are required to investigate whether the natural distinction of snails is caused by water body environments-induced changes of the microbial spectrum in O. hupensis snails.

Effectiveness of snail control by immersion of molluscicides through tide diversion in marshlands: a field evaluation / 中国血吸虫病防治杂志

Objective To compare the effectiveness of snail control between immersion of molluscicides through tide diversion and mollusciciding by spraying in marshland areas. Methods Immersion of 26% suspension concentrate of metaldehyde and niclosamide through tide diversion and spraying 26% suspension concentrate of metaldehyde and niclosamide alone were employed for snail control in two neighboring snail-breeding marshlands, and snails were surveyed before and after mollusciciding. The mortality of snails and the density of living snails were estimated. Results The density of living snails reduced by 72.19% and 100.00% 1 and 2 years after immersion of 26% suspension concentrate of metaldehyde and niclosamide through tide diversion, and 5.93% and 18.15% 1 and 2 years after spraying 26% suspension concentrate of metaldehyde and niclosamide alone. Conclusion Immersion of 26% suspension concentrate of metaldehyde and niclosamide through tide diversion is significantly superior to spraying 26% suspension concentrate of metaldehyde and niclosamide along for snail control, and implementation of immersion of 26% suspension concentrate of metaldehyde and niclosamide through tide diversion for more than 2 successive years may achieve a higher snail control efficiency.

Effectiveness of snail control by immersion of molluscicides through tide diversion in marshlands: a field evaluation / 中国血吸虫病防治杂志

Objective To compare the effectiveness of snail control between immersion of molluscicides through tide diversion and mollusciciding by spraying in marshland areas. Methods Immersion of 26% suspension concentrate of metaldehyde and niclosamide through tide diversion and spraying 26% suspension concentrate of metaldehyde and niclosamide alone were employed for snail control in two neighboring snail-breeding marshlands, and snails were surveyed before and after mollusciciding. The mortality of snails and the density of living snails were estimated. Results The density of living snails reduced by 72.19% and 100.00% 1 and 2 years after immersion of 26% suspension concentrate of metaldehyde and niclosamide through tide diversion, and 5.93% and 18.15% 1 and 2 years after spraying 26% suspension concentrate of metaldehyde and niclosamide alone. Conclusion Immersion of 26% suspension concentrate of metaldehyde and niclosamide through tide diversion is significantly superior to spraying 26% suspension concentrate of metaldehyde and niclosamide along for snail control, and implementation of immersion of 26% suspension concentrate of metaldehyde and niclosamide through tide diversion for more than 2 successive years may achieve a higher snail control efficiency.

Molluscicidal effects of different formulations of niclosamide ethanolamine salt in marshlands / 中国血吸虫病防治杂志

Objective To evaluate the molluscicidal effects of different formulations of niclosamide ethanolamine salt in marshlands. Methods The molluscicidal effects of spraying with 25% suspension concentrate of niclosamide ethanolamine salt (25% SCN) and 50% wettable powder formulation of niclosamide ethanolamine salt (50% WPN), and dusting with 4% niclosamide ethanolamine salt dustable powder (4% DP) for controlling Oncomelania hupensis snails were investigated and compared in the fields, and the cost-effectiveness was analyzed. Results The corrected mortalities and the reduced rates of density of snails were 54.37%, 91.70%, 92.76%, 79.50%, and 59.55%, 95.93%, 97.63%, 94.15%, respectively, on 3, 7, 15, 30 d after spaying with 25% SCN, those on 3, 7, 15, 30 d after dusting with 4% DP were 59.10%, 91.83%, 95.56%, 93.34% and 65.03%, 94.93%, 97.61%, 97.28%, respectively; and those on 3, 7, 15, 30 d after spraying with 50% WPN were 76.29%, 91.68%, 93.12%, 81.59% and 81.24%, 97.02%, 97.84%, 95.27%, respectively. The cost of spraying with 25% SCN was 0.21 Yuan/m2, that of dusting with 4% DP was 0.39 Yuan/m2, and that of spraying with 50% WPN was 0.23 Yuan/m2 for snail control in the marshland. The cost of reduced one percentage of the corrected mortalities and the density of snails in controlling snails by 25% SCN, 4% DP and 50% WPN on 15 d were 22.68, 40.63, 25.17 Yuan and 21.54, 39.78, 23.95 Yuan, respectively. Conclusions The three different formulations of niclosamide are reliable and effective for snail control in marshlands. There are some differences among the different molluscicides in start time, pharmacodynamic characteristics, spraying methods in the field, cost of snail control, and influencing factors. Therefore, we need reasonably select the suitable molluscicides according to the environmental characteristics and working condition.

Molluscicidal effects of different formulations of niclosamide ethanolamine salt in marshlands / 中国血吸虫病防治杂志

Objective To evaluate the molluscicidal effects of different formulations of niclosamide ethanolamine salt in marshlands. Methods The molluscicidal effects of spraying with 25% suspension concentrate of niclosamide ethanolamine salt (25% SCN) and 50% wettable powder formulation of niclosamide ethanolamine salt (50% WPN), and dusting with 4% niclosamide ethanolamine salt dustable powder (4% DP) for controlling Oncomelania hupensis snails were investigated and compared in the fields, and the cost-effectiveness was analyzed. Results The corrected mortalities and the reduced rates of density of snails were 54.37%, 91.70%, 92.76%, 79.50%, and 59.55%, 95.93%, 97.63%, 94.15%, respectively, on 3, 7, 15, 30 d after spaying with 25% SCN, those on 3, 7, 15, 30 d after dusting with 4% DP were 59.10%, 91.83%, 95.56%, 93.34% and 65.03%, 94.93%, 97.61%, 97.28%, respectively; and those on 3, 7, 15, 30 d after spraying with 50% WPN were 76.29%, 91.68%, 93.12%, 81.59% and 81.24%, 97.02%, 97.84%, 95.27%, respectively. The cost of spraying with 25% SCN was 0.21 Yuan/m2, that of dusting with 4% DP was 0.39 Yuan/m2, and that of spraying with 50% WPN was 0.23 Yuan/m2 for snail control in the marshland. The cost of reduced one percentage of the corrected mortalities and the density of snails in controlling snails by 25% SCN, 4% DP and 50% WPN on 15 d were 22.68, 40.63, 25.17 Yuan and 21.54, 39.78, 23.95 Yuan, respectively. Conclusions The three different formulations of niclosamide are reliable and effective for snail control in marshlands. There are some differences among the different molluscicides in start time, pharmacodynamic characteristics, spraying methods in the field, cost of snail control, and influencing factors. Therefore, we need reasonably select the suitable molluscicides according to the environmental characteristics and working condition.

Field molluscicidal effect of water-free formulations of niclosamide ethanolamine salt against Oncomelania hupensis snails in a marshland / 中国血吸虫病防治杂志

To evaluate the molluscicidal effects of various water-free formulations of niclosamide ethanolamine salt against Oncomelania hupensis in the field of marshlands along the Yangtze River.The river beach with O. hupensis snails were selected as the test field in the marshland along the Yangtze River in Pukou District, Nanjing City. A molluscicidal experiment was carried out by the mechanical dusting method with the dustable powder (DP), powder-granule (PG), granule (GR) of niclosamide ethanolamine salt respectively. The snail mortality, corrected mortality, and the reduced rate of snails’ density were parallel compared among DP, PG and GR.On the 3rd day after the dusting, the snail mortality rates were 66.67%, 67.24%, and 66.87% in the DP, PG, and GR groups respectively, on the 7th day after the dusting, the snail mortality rates were 75.36%, 79.73%, and 73.97% in the DP, PG, and GR groups respectively, and there was no significant difference among the groups (χ2 = 0.006, 0.895, both P > 0.05). On the 15th day after the dusting, the snail mortality rates were 86.92%, 72.86%, and 71.43% in the DP, PG, and GR groups respectively, and there was a significant difference among the groups (χ2 = 9.709, P < 0.01). The snail mortality in the DP group was significantly higher than that in the PG, and GR groups. The curves of the snail corrected mortality and reduced rate of snails’density presented steadily rising trends in the DP group, but presented falling trends in the PG and GR groups on the 15th day after the dusting.The molluscicidal effect of DP is stable and effective in the marshland along the Yangtze River, but the drift of the powder is still not effectively controlled. It is necessary that the different dosage forms are perfected.

Surveillance and risk assessment system of schistosomiasis epidemic focus in Hankou marshland of Wuhan City / 中国血吸虫病防治杂志

To construct a monitoring and risk assessment system of schistosomiasis epidemic focus in marshland, so as to grasp the risk of schistosomiasis transmission, and to provide the technical support for targeted prevention and control measures.The crowd and the risk source of schistosomiasis in Hankou marshland in Wuhan City were monitored to grasp the risk factors of schistosomiasis. The risk level was evaluated by the three-dimensional risk matrix and three-dimensional visualization method.The total numbers of people on holidays and working days were 59 582 and 36 382 persontimes a day respectively in Hankou marshland. Fishing and swimming were the most common ways to contact the river water. The most majority of the people exposed to river water were male (73.9%), retirees (36.1%), local residents (69.7%) and people whose income was 1000 – 3000 yuan per month (52.1%), and the awareness of protection of them was low. In spring, the average density of living Oncomelania hupensis snails was 0.993/0.1 m2, the rat density was 7.72%, and the density of wild feces was 0.78/hm2. In autumn, the average density of living snails was 0.596 /0.1 m2, the rat density was 5.22%, and the density of wild feces was 0.32/hm2. The average density of living snails, the rat density and the density of wild feces were reduced by 39.9%, 32.4% and 59.0% respectively in autumn compared with those in spring. The risk assessment results of three-dimensional matrix showed that part 1 and part 2 were medium risk, part 3 was high risk and part 4 was maximum risk. The risk assessment results of the visualization method showed that the risk level increased from part 1 to part 4, which were basically consistent with the results of the risk matrix.There is a relatively large risk of schistosome infection in Hankou marshland in 2013. The surveillance and risk assessment system of epidemic focus is feasible and scientific.

Changes of serum anti-schistosome antibody levels in schistosomiasis japoni-ca patients after treatment / 中国血吸虫病防治杂志

Objective To investigate the changes of serum anti-schistosome antibody titers in schistosomiasis japonica pa-tients after treatment,in order to provide the evidence for formulating the schistosomiasis surveillance program in marshland and lake regions.Methods Upon prospective cohort study,the stool examination positive schistosomiasis patients and blood exami-nation positive suspected patients(the titer was more than 1:80,including 1:80)were selected as the research objects in Jian-gling County in 2014,and they received the 2-day praziquantel therapy.Half year,one year and two years after the treatment, their blood samples and fecal samples were collected for IHA anti-schistosome antibody detections and schistosome egg and mira-cidium detections. Results In 2014,the stool examination positives were 251,and the majority of them were over 41 years old,accounting for 93.23%(234/251);581 cases of high antibody titers were detected by the IHA method,and the majority of them were over 41 years old,accounting for 89.16%(518/581).Half year,one year and two years after the treatment,among the stool examination positives,the negative conversion rates of stool positives were 99.60%(250/251),100%(239/239)and 100%(234/234)respectively and the negative conversion rates of antibody positives were 21.91%(55/251),64.11%(156/239)and 76.89%(193/234)respectively.In the high antibody titer positives,the negative conversion rates were 38.04%(221/581),64.11%(359/560),and 77.86%(429/551)respectively,Half year,one year and two years after the treatment.There were statistically significant differences among the antibody negative conversion rates by χ2test(χ2=77.538,183.412,25.469 respectively,all P<0.001).The geometric mean values of antibody titers of different durations between 2 groups were analyzed by 2-independent-samples T test,and the geometric mean values of antibody titers between the 2 groups were different before the treatment(t=23.576,P<0.01),but the geometric mean values of antibody titers between the 2 groups were not different 6 months,1 year and 2 years after the treatment(t=-0.046,1.165, -0.132,P=0.964, 0.245,0.895 respectively). Conclu-sions The levels of serum anti-schistosome antibody degrade slowly in schistosomiasis japonica patients after the treatment, and the results of IHA tests cannot distinguish the current schistosome infection from previous schistosome infection.Therefore, it is necessary to develop the specific diagnostic technology for schistosome infection in order to meet the need of monitoring.

Effects and cost of four formulations of niclosamide ethanolamine salt in On-comelania hupensis snail control in field / 中国血吸虫病防治杂志

Objective To investigate the effects and cost of four formulations of niclosamide ethanolamine salt in Oncomela-nia hupensis snail control in the field in marshland and lake regions,so as to provide the evidence for drawing up the plan of mol-luscicide using in schistosomiasis endemic areas. Methods One drainage channel and one channel without water in the same area with snails in Jiangling County,Jingzhou City were selected as the research fields. The drainage channel was divided into 9 sections,except one section as a blank control group where the natural death rate of snails was observed only,and the remaining 8 sections were taken as the observation groups,where different dosages of 4％niclosamide ethanolamine salt powder,5％ni-closamide ethanolamine salt granules,25％ niclosamide ethanolamine salt suspending agent,26％ metaldehyde and ni-closamide ethanolamine salt suspending agent,and 50％niclosamide ethanolamine salt wettable powder were used re-spectively. The channel without water were divided into 4 sections,except one section as a blank control group,the oth-er 3 segments were taken as the observation groups,where 4％niclosamide ethanolamine salt powder,5％niclosamide ethanolamine salt granules,and 50％ niclosamide ethanolamine salt wettable powder were used respectively. Before and after spraying molluscicide for 7 days and 15 days,the system sampling method was used to observe the effects of snail control. Meanwhile,the unit cost method was used to calculate the costs of the different mulluscicide formulations abovementioned in unit area(1 m2). Results In the field at the drainage channel,the snail mortality rates of the groups spraying 4％niclosamide ethanolamine salt powder(50 g/m2),5％niclosamide ethanolamine salt granules(40 g/m2),25％ niclosamide ethanolamine suspending agent,26％ metaldehyde and niclosamide ethanolamine salt sus-pending agent,and 50％niclosamide ethanolamine salt wettable powder(2 g/m2 and 4 g/m2)for 7 days were 79.52％-97.87％,while the rates after spraying for 15 days were 71.00％-96.30％,and compared with those before spraying, the differences were statistically significant(all P<0.01). For the groups spraying with 2 g/m2 or 4 g/m2 suspending agent as well as wettable powder for 7 days,the snail mortality rates were significantly different(both P<0.05). In the field at the channel without water,the snail mortality rates of the 3 observation groups after spraying molluscicide for 7 days were 97.14％-100％,while for 15 days were 94.32％-100％,and compared with the rates before spraying,all the differences were statistically significant(all P<0.01). The unit costs per 1 m2 of the molluscicide abovementioned were ranged from 0.280 Yuan to 0.416 Yuan. Conclusions In marshland area inside embankment,the molluscicide formulations of the powder and granule are suitable for the environments without water or with instability water level , while the molluscicide formulations of the suspended agents and wettable powder are suitable for the water environment. Though the unit cost of powder is the lowest,the molluscicide in this formulation flies away seriously.

Practice of engineering management and its effect on schistosomiasis control in Hankou marshland,Wuhan City / 中国血吸虫病防治杂志

Objective To investigate the Oncomelania hupensis snail control effect of schistosomiasis control engineering in marshland within Wuhan City. Methods The engineering measures including surface barrier removal,molluscicide,flatting surface,topsoil stripping,topsoil covering and ditch renovation were applied to transform Hankou marshland. Then the corre-sponding technical parameters of engineering measures were put forward. The situation of snails was analyzed before and after the transform project. Results The total length and area of the project were 6015 m and 87.21 hm2,respectively,including 17.44 hm2 of topsoil landfill,52.08 hm2 of topsoil covering and 23 new ditches. After the transformation,the average length of the new groove,the groove top width,groove depth,height difference,and the average values of slopes and ditch bottom slope were all increased,while the average values of the width and height of the ditch were decreased. At the same time,the marsh-land beach surface had a new slope that the embankment was higher than the river and no living O. hupensis snails were found then. Conclusions The snail breeding environment in Hankou marshland has been effectively changed by the project. Howev-er,the constant monitoring and engineering management are still needed to consolidate the effect.

Surveillance and risk assessment system of schistosomiasis in Jiangsu Prov-inceⅢRisk of schistosomiasis transmission in the area along the Yangtze River in Yang-zhou City / 中国血吸虫病防治杂志

Objective To evaluate the potential risk of schistosomiasis transmission in the area along the Yangtze River in Yangzhou City,so as to provide evidences for establishing a post?transmission surveillance system for schistosomiasis in marsh?land regions. Methods The water infectivity,floating boatmen and fishermen infection,reservoir host infection and wild feces contamination were investigated in five districts/counties along the Yangtze River in Yangzhou City,including Guangling,Hanji?ang,Jiangdu,Yizheng and Development Zone,and the transmission factors and risky characteristics were assessed after inter?ruption of schistosomiasis transmission in marshland regions. Results A total of 15 key water regions were identified in the area along the Yangtze River in Yangzhou City in 2015. A total of 1 500 sentinel mice were placed,after breeding,their overall sur?vival rate was 99.33%;1 490 were dissected,with no schistosome infection. Of the 5 576 floating boatmen and fishermen exam?ined,no schistosome infection was observed,and among the 3 566 domestic animals(including 171 cattle,1 895 sheep and 1 500 pigs),no infections were detected. During the period between January and March,2016,there were 3 200 mouse traps placed on 8 marshlands,and 62 wild mice were captured from 6 marshlands,with a capture rate of 1.94%,and no schistosome?infected wild mice were seen. In addition,there were 35 pieces of fresh wild feces captured from 7 marshlands,including 11 pieces of bovine feces(31.43%),17 pieces of sheep feces(48.57%),2 pieces of dog feces(5.71%)and 5 pieces of other feces (14.29%),and no infections were detected. Conclusions There is a low risk of schistosomiasis transmission in the area along the Yangtze River in Yangzhou City. However,the contamination of feces from bovine and sheep that are freely pastured on marshlands is a big threat to schistosomiasis control.

Schistosomiasis control effect of agricultural integrated development in Tie-ban Marshland of Yangtze River / 中国血吸虫病防治杂志

Objective To evaluate the schistosomiasis control effect of the comprehensive measures that focused on beach?land smoothing and tillage cultivation in Tieban Marshland,Wuhan Section of the Yangtze River. Methods From 2011 to 2015, before and after the comprehensive control,the Oncomelania hupensis snail situations in Tieban Marshland were investigated in spring annually,and the residents aged 6-65 years in Huayuan Community which was next to the marshland were examined to un?derstand their schistosome infection status. In late July,2014,the sentinel mouse surveillance was carried out. Moreover,the eco?nomic effectiveness of comprehensive development was evaluated. Results The schistosome infection rates of residents in 2011 (before the comprehensive control),2012(after the comprehensive control),and 2013 were 0.72%(3/414),0.37%(2/536)and 0.31%(1/326),respectively,and no schistosomiasis patients were found in 2014 and 2015. The snail area,the occurrence rate of frames with snails,and the average density of living snails in Tieban Marshland in 2005 decreased by 22.18%,97.83% and 98.25%,respectively compared to those in 2011,and no schistosome infected snails were found. No positive mice were found in the sentinel mouse surveillance. The annual net income of Tieban Marshland increased by 233.33%compared to that before the comprehensive development. Conclusion The endemic situation of schistosomiasis and snail situation declined significantly af?ter the comprehensive development in Tieban Marshland,and the economic and social benefits are significant.

Development and application of communication materials for participatory health education of schistosomiasis in fishermen and boatmen of Poyang Lake region / 中国血吸虫病防治杂志

Objective To design and develop new types of health education materials which are suitable for fishermen and boatmen in endemic areas of marshland and lake regions,and to observe their application effects. Methods A total of 292 adult fishmen and boatmen who lived in Houshan Village,Yugan County,the schistosomiasis endemic area of Poyang Lake Re?gion,were selected randomly and investigated by questionnaires to understand the status of their knowledge,attitudes,practic?es on schistosomiasis control as well as the channels for getting information on schistosomiasis control and the materials that they were willing to accept. Then the information and materials suitable for the target population were developed together by the re?searchers and the volunteers of the villagers through focus group discussions,personal interviews and the Delphi method. Re?sults A series of participatory health education materials of schistosomiasis control targeted to the fishmen and boatmen were developed,including 2 live posters,2 picture puzzles,2 short opusculums and one song about schistosomiasis control. The field application showed that 98.97%,84.38%,78.35% and 80.93% of the participants considered those materials had scientificity, intelligibility,interestingness and practicability,respectively. Conclusion The participatory health education materials of schistosomiasis control is suitable for fishmen and boatmen,which can be used for reference by other endemic areas in marsh?land and lake regions.

Comparison study on sampling methods of Oncomelania hupensis snail sur-vey in marshland schistosomiasis epidemic areas in China / 中国血吸虫病防治杂志

Objective To optimize and simplify the survey method of Oncomelania hupensis snail in marshland endemic re?gion of schistosomiasis and increase the precision,efficiency and economy of the snail survey. Methods A quadrate experimen?tal field was selected as the subject of 50 m×50 m size in Chayegang marshland near Henghu farm in the Poyang Lake region and a whole?covered method was adopted to survey the snails. The simple random sampling,systematic sampling and stratified ran?dom sampling methods were applied to calculate the minimum sample size,relative sampling error and absolute sampling error. Results The minimum sample sizes of the simple random sampling,systematic sampling and stratified random sampling meth?ods were 300,300 and 225,respectively. The relative sampling errors of three methods were all less than 15%. The absolute sampling errors were 0.221 7,0.302 4 and 0.047 8,respectively. Conclusion The spatial stratified sampling with altitude as the stratum variable is an efficient approach of lower cost and higher precision for the snail survey.

Effects of comprehensive schistosomiasis control in marshlands of Pukou District,Nanjing City / 中国血吸虫病防治杂志

Objective To evaluate the effects of comprehensive schistosomiasis control in marshlands of Pukou District Nanjing City so as to provide the evidence for developing the strategy of the disease control. Methods The information of the prevention and control of schistosomiasis was collected in Pukou District from 2004 to 2013. The variations of the infection rates of human livestock and Oncomelania hupensis snails were analyzed. Results In 2013 the area with snails in the entire dis-trict was 384.09 hm2 which was 66.24%decrease compared to 1 137.61 hm2 in 2004. Moreover after 2008 no infected-snails and schistosomiasis patients were found and both the density of live snails and serum positive rate of schistosomiasis declined with years. Conclusions After the comprehensive prevention and control is conducted the schistosomiasis situation in Pukou District is stable. However in order to consolidate the results it is still essential to continue monitoring the previous infected snail environments and implementing the comprehensive prevention and control measures.

Molluscicidal effects of 3 molluscicides by spraying and poudrage methods in dry season / 中国血吸虫病防治杂志

Objective To evaluate the effects of 3 molluscicides namely 5%niclosamide ethanolamine granules,4%“Luo-wei”(Tea-seed distilled saponins,TDS)and 50%wettable powder of niclosamide ethanolamine salt(WPN)by spraying and pou-drage methods in marshland and lake regions in dry season. Methods An environment with a high snail density was chosen as the experimental field,then the spraying and poudrage experiments were carried out in the field to assess the molluscicidal effects of 5%niclosamide ethanolamine granules,TDS and WPN delivered by spraying and poudrage methods with a concentration of 30, 6 and 2 g/m2,respectively,and the molluscicidal effects of the 3 drugs by the two methods were evaluated and compared in differ-ent time. Results After the delivery for 15 d,the adjusted snail death rates of the 5%niclosamide ethanolamine granules,TDS and WPN in the spraying experiment were 79.00%,82.29%and 84.83%,respectively,and those in the poudrage experiments were 97.42%,95.27% and 96.62%,respectively. Conclusion The molluscicidal effect of poudrage method is better than the spraying method,and the former is worthy of further extension and application in the marshland in dry season.

Selection of epidemic indicators for schistosomiasis GIS platform in Dongting Lake area / 中国血吸虫病防治杂志

Dongting Lake area is one of the major marshland schistosomiasis endemic areas in China. In recent years spatial epidemiology is widely used in the research of schistosomiasis which is a new opportunity to break through the current wander-ing situation of schistosomiasis control. In this article both the generalized and Dongting-Lake-specific epidemic indicators of schistosomiasis are reviewed to provide the basis to construct the schistosomiasis Geographic Information System GIS database of Hunan Province.

Molluscicidal effect of 5%niclosamide ethanolamine granules against Onco-melania hupensis in a marshland field / 中国血吸虫病防治杂志

Objective To investigate the molluscicidal effect of 5%niclosamide ethanolamine granules against Oncomela-nia hupensis in a marshland field. Methods The 5%niclosamide ethanolamine granules were sprayed at a dose of 40 g/m2 on 3 snail-breeding marshlands in Yangzhong City of Jiangsu Province to assess its field molluscicidal actions while 26%suspension concentrate of metaldehyde and niclosamide MNSC) at a dose of 4 g/m2 and fresh water served as controls. Results After seven days spraying, 5%niclosamide ethanolamine granules resulted in a of snail mortal85.42%ity while the mortality rates of snails were 82.35% and 2.86% in the MNSC and water control groups respectively. Conclusion 5% niclosamide ethanol-amine granules exhibit a high molluscicidal activity which is suitable to be used in the mashland.