Background: Schistosomiasis remains a major public health concern in China. Since 2004, an integrated strategy was developed to control the transmission of Schistosoma japonicum in China. However, the long-term effectiveness of this integrated strategy for the interruption of schistosomiasis transmission remains unknown in the mountainous and hilly regions of China until now. This longitudinal study aims to evaluate the effectiveness of the integrated strategy on transmission interruption of schistosomiasis in Sichuan Province from 2005 through 2014.Methods: The data regarding replacement of bovines with machines, improved sanitation, access to clean water, construction of public toilets and household latrines, snail control, chemotherapy, and health education were captured from the annual report of the schistosomiasis control programmes in Sichuan Province from 2005 to 2014, and S. japonicum infection in humans, bovines and snails were estimated to evaluate the effectiveness of the integrated strategy.Results: During the 10-year period from 2005 through 2014, a total of 536 568 machines were used to replace bovines, and 3 284 333 household lavatories and 15 523 public latrines were built. Tap water was supplied to 19 116 344 residents living in the endemic villages. A total of 230 098 hm(2) snail habitats were given molluscicide treatment, and 357 233 hm2 snail habitats received environmental improvements. There were 7 268 138 humans and 840 845 bovines given praziquantel chemotherapy. During the 10-year study period, information, education and communication (IEC) materials were provided to village officers, teachers and schoolchildren. The 10-year implementation of the integrated strategy resulted in a great reduction in S. japonicum infection in humans, bovines and snails. Since 2007, no acute infection was detected, and no schistosomiasis cases or infected bovines were identified since 2012. In addition, the snail habitats reduced by 62.39% in 2014 as compared to that in 2005, and no S. japonicum infection was identified in snails since 2007. By 2014, 88.9% of the endemic counties achieved the transmission interruption of schistosomiasis and transmission control of schistosmiasis was achieved in the whole province in 2008.Conclusion: The government-directed and multi-department integrated strategy is effective for interrupting the transmission of schistosomiasis in the mountainous and hilly regions of China.

Schistosomiasis is a parasitic disease that affects over 200million people worldwide in at least 76 countries, ranking second only after malaria in terms of its socio-economic and public health importance in tropical and subtropical areas of the world. Chinese surveillance data since the mid-1950s have shown that endemic areas are divided into three types based on geographical, ecological and epidemiological factors, such as marshland and lake region, plain region with waterway networks and hilly and mountainous region. As confirmed by numerous epidemiological investigations, schistosomiasis endemic areas of the mountainous type are distributed in 178 counties in 11 provinces of The People's Republic of China. Over the past several decades great success in transmission control has been achieved by implementation of control strategies that were suitable for the mountainous and hilly endemic region.

OBJECTIVE:To establish an index system of the key factors of elimination of schistosomiasis.METHODS:A questionnaire was designed based on the reference review, and 24 scientists working in the field of schistosomiasis control or research or management were investigated by using the Delphi method. The importance of each index reflecting the endemicity of schistosomiasis wis scored by each scientist. The assessing system for key factors of eliminating schistosomiasis was established, and the normalized weight and combined weight were calculated.RESULTS:The assessing system included three indexes in the first grade, seven indexes in the second grade and thirteen indexes in the third grade. Among the indexes in the first grade, the normalized weights of endemicity, natural environment and social environment were 0.371 1, 0.339 5, and 0.289 4, respectively. Among the indexes in the second grade, the economy showed the highest combined weight of 0.289 4 while the agriculture and sanitation both showed the lowest score of 0.112 7. Among the indexes in the third grade, the infection rate of animals showed the highest combined weight of 0.124 6 while the agriculture and plant structure both showed the lowest score of 0.053 0.CONCLUSION:The indexes of the assessing system provide the scientific evidence for surveillance work when elirnination of schistosomiasis.

Objective This article introduced the present status of schistosomiasis prevention and control in Sichuan province. The key difficulties in schistosomiasis prevention and control included lagged prevention and control measures,snail control in hilly environments,floating population management,construction of the ecological wetland and the influence of natural disasters on schistosomiasis; based on which corresponding suggestions were proposed. With reflections on the current status,this article revealed that prevention and control philosophy had failed to adapt to the social economic development. Integrated schistosomiasis prevention and control strategies were analyzed with emphasis on infection source,schistosomiasis transmission blocking criteria,and standard evaluation scheme. Therefore,the current focus of work is comprehensively impelling the procession of standardization across the province in 2015; afterwards,surveillance system need to be strengthened,as well as timely detection and extinguish of the epidemic are both warranted to consolidate the blocking achievements.

OBJECTIVE:To evaluate the effect of schistosomiasis control in Lushan earthquake-stricken areas in Sichuan Province, so as to provide the evidence for formulating appropriate measures for schistosomiasis prevention and control.METHODS:According to the data of historical schistosomiasis prevalence, 5 villages were selected as research sites and field investigations were conducted.RESULTS:The average density of Oncomelania hupensis snails was 0.41 snails/0.1 m2, and there were no schistosome-infected snails. There were no acute schistosomiasis cases in these five villages. For local residents, the health education leaflets were more suitable than warning signs, and for migrant population, they were more concerned about the warning signs.CONCLUSION:After the implementation of effective prevention and control works, the epidemic risks of schistosomiasis have been controlled. However, the health education, surveillance, and prevention measures for schistosomiasis still need to be persisted in.

Objective To understand the epidemic situation of schistosomiasis in transmission blocking area in Sichuan,and thus to provide references for formulating control strategies.Methods Historical data and worksheets of current schistosomiasis control in 2007-2012 were collected and analyzed.Results The historical snail area in the 27 transmission blocking counties accounted for 8.29% of total historical snail area in Sichuan province.No schistosomiasis patient and animal was reported.The snail area ranged from 611 720 m2 to 1 390 400 m2.In 2012,snail emerged in 20 of 27 counties,and snail area in 6 counties surpassed history by 2%.The workload for controlling schistosomiasis showed an increasing trend as a whole.Conclusion The epidemic situation of schistosomiasis has stayed stable since 2007 with a slight regaining.Preventive measures such as snail control,people and livestock regulation should be timely strengthened.

OBJECTIVE To study suitable schistosomiasis control to migrant population by new pattern in order to increase their compliance of exam and treatment and knowledge rate of schistosomiasis control.METHODS The migrant population from schistosomiasis endemic villages were collected as intervention group by purposive sampling.Besides routine schistosomiasis control,the mobile phone message with knowledge of schistosomiasis control,exam and treatment information were distributed to migrant population regularly.The questionnaire of knowledge of schistosomiasis control,compliance of exam and treatment and acceptance of intervention pattern were surveyed before and after intervention.RESULTS 501 of migrant population were selected as intervention group.The compliance rate of schistosomiasis exam and treatment rose from 19.36% to 74.05%(χ2 = 301.011,P = 0.000).The awareness rate of control knowledge about schistosomiasis rose from 56.19% to 71.38%(χ2 = 126.214,P = 0.000).The rate of correct schistosomiasis control behavior rose from 60.68% to 67.30%(χ2 = 12.079,P = 0.001).91.13% people expressed being fond of this pattern.CONCLUSION The mobile phone message can improve the compliance of schistosomiasis exam and treatment of migrant population rapidly,increase their awareness rate of schistosomiasis control knowledge.This pattern can remedy the routine control limitation due to migrant population.

OBJECTIVE:To assess the impact of the "4 x 20" Lushan Earthquake on the risk of schistosomiasis transmission in Lushan and Tianquan counties, so as to provide the evidence for formulating appropriate measures for schistosomiasis prevention and control.METHODS:Based on a comprehensive literature review, an analysis of schistosomiasis monitoring data in the earthquake affected counties, and a field investigation, a rapid assessment on the impact of the earthquake on schistosomiasis was conducted.RESULTS:Lushan and Tianquan counties were two endemic areas of schistosomiasis with high transmission level in history, especially Lushan County where Oncomelania snail distribution/density was the highest in Sichuan Province. After the earthquake, the streams and damaged ditches were blocked up, potentially leading to the spread of Oncomelania snails, and the damaged sanitary facilities may also lead to the release of excrement, contaminating the environment where snails resided. Meanwhile, the people who were relocated due to the earthquake may have higher exposures to contaminated environment. In addition, increasing population mobility (e.g. relief workers) also had the potential to bring infection sources in the earthquake affected areas. Further, animals, which may serve as reservoirs for the parasite such as homeless dogs, may also add the complexity of local schistosomiasis transmission.CONCLUSIONS:The epidemic risk of schistosomiasis in Lushan and Tianquan counties is high. To prevent the outbreak and epidemic of schistosomiasis, the victim settlements should be established appropriately and the excrement should be managed carefully. Meanwhile, the snail control should be carried out in the high-risk environments. The health education, monitoring, patient treatments and expanded chemotherapy should be carried out and strengthened.

OBJECTIVE:To assess whether Beichuan County reaches the national standard of schistosomiasis transmission interruption.METHODS:Three villages in Beichuan County were sampled as assessment spots, and the schistosomiasis infections of residents and domestic animals, the status of Oncomelania snails and the past records were assessed according to the Criteria for Control and Elimination of Schistosomiasis in China.RESULTS:No local schistosome infections were found in residents and cattle for successive 5 years and no snails were found for 2 successive years in the 3 villages. The files were documented completely. All the indices reached the national standard of schistosomiasis transmission being interrupted.CONCLUSION:Beichuan County has reached the national standard of schistosomiasis transmission interruption. However, the endemic surveillance of schistosomiasis still needs to continue.

Molecular genetic tools are needed to address questions as to the source and dynamics of transmission of the human blood fluke Schistosoma japonicum in regions where human infections have reemerged, and to characterize infrapopulations in individual hosts. The life stage that interests us as a target for collecting genotypic data is the miracidium, a very small larval stage that consequently yields very little DNA for analysis. Here, we report the successful development of a multiplex format permitting genotyping of 17 microsatellite loci in four sequential multiplex reactions using a single miracidium held on a Whatman Classic FTA indicating card. This approach was successful after short storage periods, but after long storage (>4 years), considerable difficulty was encountered in multiplex genotyping, necessitating the use of whole genome amplification (WGA) methods. WGA applied to cards stored for long periods of time resulted in sufficient DNA for accurate and repeatable genotyping. Trials and tests of these methods, as well as application to some field-collected samples, are reported, along with the discussion of the potential insights to be gained from such techniques. These include recognition of sibships among miracidia from a single host, and inference of the minimum number of worm pairs that might be present in a host.

OBJECTIVE:To understand the dynamics of schistosome antibodies in population in mountainous schistosomiasis low endemic regions, China, so as to provide the evaluation reference for immunodiagnosis.METHODS:The people who consecutively received the indirect heamagglutination assay (IHA) for schistosomiasis and Kato-Katz technique were enrolled in this study in Guixiang Village, Danling County, Sichuan Province from 2006 to 2011. The positive rates for schistosome antibodies, antibody titers and eggs per gram (EPG) were analyzed.RESULTS:A total of 353 people were investigated in this study from 2006 to 2011. The positive rates for schistosome antibodies decreased from 20.73% to 13.67%, and the geometric mean reciprocal titer (GMRT) decreased from 1.63 to 1.06. The antibodies tended to be negative in most antibody-positive people and the GMRT decreased gradually. The antibodies remained negative in most antibody-negative people. After chemotherapy in parasitology confirmed patients, the positive rate for schistosome antibodies decreased from 100% to 20%, and the GMRT decreased from 34.29 to 1.58. There was a highly positive correlation between GMRT and EPG (r = 0.94, P < 0.05).CONCLUSION:The positive rate for schistosome antibodies in population in mountainous schistosomiasis low endemic regions is relatively high (13.67%). The standardization of immunodiagnostic methods is necessary and the suitable diagnostic reagents should be developed in this region.

Molecular genetic tools are needed to address questions as to the source and dynamics of transmission of the human blood fluke in regions where human infections have reemerged, and to characterize infrapopulations in individual hosts. The life stage that interests us as a target for collecting genotypic data is the miracidium, a very small larval stage that consequently yields very little DNA for analysis. Here, we report the successful development of a multiplex format permitting genotyping of 17 microsatellite loci in four sequential multiplex reactions using a single miracidium held on a Whatman Classic FTA indicating card. This approach was successful after short storage periods, but after long storage (>4 years), considerable difficulty was encountered in multiplex genotyping, necessitating the use of whole genome amplification (WGA) methods. WGA applied to cards stored for long periods of time resulted in sufficient DNA for accurate and repeatable genotyping. Trials and tests of these methods, as well as application to some field-collected samples, are reported, along with the discussion of the potential insights to be gained from such techniques. These include recognition of sibships among miracidia from a single host, and inference of the minimum number of worm pairs that might be present in a host.

Objective To provide evidence for developing the Schistosomiasis control strategy and evaluation of the control effect by understanding the epidemic situation of Schistosomiasis in Danleng county.Method Data of Schistosomiasis Mornitoring in Guixiang village,Shuangqiao town,Danleng county of Sichuan Province from 2005 to 2010 was analyzed.Results From 2005 to 2010,602,603,631,615,601 and 564 villagers were checked respectively in each year,the numver of infections were 9,9,6,5,0 and 0,with the infection rates of 1.50%,1.49%,0.95%,0.81%,0 and 0 respectively.Among these villagers,there was one infected under 20 years old;318,325,341 and 336 villagers aged 20-49 years were yearly checked from 2005 to 2008,in which 3,7,4 and 4 cases were checked positive;159,173,188 and 173 villagers aged over 50 years were yearly checked from 2005 to 2008,in which 5,2,2 and 1 cases were checked positive.There was no fecal positive checked out in 2009 and 2010.No acute or late-stage Schistosomiasis patients was found.Annually checked 9,3,3,4,4 and o cattles,without positive one.The snail areas were 49 660,42 130,54 130,54 330,51 440 and 51 390 m2 in each year,with the densities of living snails of 2.38,1.09,1.52,1.51,1.49 and 1.29/0.11 m2,no new snail area or infected snails was found.Conclusion Most of Schistosomiasis infected people in Danleng county were adults,and the infection rate of people aged over 50 was high,the control of those people should be pay more attention to.The effect of comprehensive measures with emphasis on source of infection is distinct.The ability of scientific control and comprehensive management of Schistosomiasis through multi-sectoral cooperation should be improved.

The comprehensive control pattern centering on health education, deworming and improving drinking water and lavatories was adopted to control soil-transmitted nematodiasis in Danling County, Sichuan Province from 2007-2009. In 2009, the infection rate of soil-transmitted nematodes decreased from 57.12% of the baseline survey in 2006 to 10.06%.

OBJECTIVETo understand the epidemic trend of schistosomiasis in Sichuan Province so as to provide the evidence for formulating schistosomiasis control strategy.METHODSAccording to the National Schistosomiasis Surveillance Protocol, the national surveillance sites in Sichuan Province were selected. The schistosomiasis surveillance was carried out continuously from 2005 to 2010.RESULTSNine national schistosomiasis surveillance sites were established in Pujiang, Guanghan, Zhongjiang, Fucheng, Dongpo, Danling, Renshou, Xichang and Dechang counties. The Oncomelania hupensis snail area decreased from 351 853 m2 in 2005 to 128 285 m2 in 2010, the snail density from 0.70 to 0.21 per 0.1 m2, the snail infection rate from 0.06% to 0, the positive rate of human serum schistosome antibody from 19.41% to 7.62%, the schistosome infection rate of human population from 1.93% to 0.10%, and the infection rate of livestock from 4.50% to 1.02%. The snails were found mainly in ditch, rice field and other moist field.CONCLUSIONSThough the endemic of schistosomiasis has reached a low level in Sichuan Province, the endemic situation fluctuates at a narrow range in some surveillance sites. Therefore, the surveillance work should be carried out continuously.

Objective To analyze the trend of schistosomiasis infection rate of the population in Sichuan province from 2003 to 2010,and apply the Grey Model(1,1) to predict the infection rate for the next 3 years and provide reference for the further policy of prevention and control.Methods Based on GM(1,1),the prediction model was set up by using the material on schistosomiasis infection rate in Sichuan Province from 2003 to 2010.Results The schistosomiasis infection rate was decreasing year by year,the model of the infection rate of the population was(1)(t+1)=-103.1157e-0.4950t+132.6545,The predicting precision of GM(1,1) was desirable in accordance with criterion of the grey model prediction assessment,the predicted values based on GM(1,1) were consistent with the actual rates from 2003 to 2010.The predicted values of future three years were 1.2590/104、0.7675/104 and 0.4678/104 respectively.Conclusion The GM(1,1) had a good fit and accurate prediction,The schistosomiasis infection rate will decline in future three years according to the predicted result,and the model can provide important reference for making strategy in those areas where were under the low infection rate.

Objective To investigate and evaluate the prevelance of human echinococcosis in Sichuan province.Methods With randomly stratified cluster sampling method,people in 31 counties in Ganzi and Aba prefectures,Sichuan province,was screened for echinococcosis using B ultrasound scanning combined with sera anti-echinococcus antibody IgG detection.The prevelance of echinococcosis in human was determined and the numbers of cases were estimated.Results The standarded prevelance of human echinococcosis in Sichuan province was to 1.06%,human cases were estimated to be around 20 000.Most human echinococcosis cases were found in Ganzi prefecture,where the prevelance of echinococcos was counted for 1.55% and the estimated human case was 15 335,mainly distributed in 8 counties including Shiqu,Seda,Ganzi,Dege,Baiyu,Luhuo,Xinlong and Litang.Whereas 48% of echinococcosis prevelance was eastimated for Aba prefecture,where 4 112 of human cases were primarily dispersed in Ruoergai,Maerkang,Aba,Jinchuan,Hongyuan,Songpan and Rangtan.Conclusion Echinococcosis was highly prevelant in 8 counties in Ganzi prefecture and in 7 counties in Aba prefecture.Control strategy towards this disease should be mainly focused on these heavily endemic counties in order to obtain more effective control outcomes.

In this study, we applied a loop-mediated isothermal amplification method for identification of human Taenia tapeworms in Tibetan communities in Sichuan, China. Out of 51 proglottids recovered from 35 carriers, 9, 1, and 41 samples were identified as Taenia solium, Taenia asiatica and Taenia saginata, respectively. Same results were obtained afterwards in the laboratory, except one sample. These results demonstrated that the LAMP method enabled rapid identification of parasites in the field surveys, which suggested that this method would contribute to the control of Taenia infections in endemic areas.

OBJECTIVE:To understand the current distribution and characteristics of patients with advanced schistosomiasis in Sichuan Province, so as to provide the scientific evidence for improving the management and treatment of advanced schistosomiasis.METHODS:The patients who had been diagnosed as advanced schistosomiasis or were supposed with advanced schistosomiasis were the objects of the investigation. The epidemiological survey and medical examination were used to investigate these persons one by one according to the national standard.RESULTS:There were 1 684 patients with confirmed diagnosis in 7 cities of Sichuan Province. There were 1 066 cases of splenomegaly including post-surgery (63.30%), 545 cases of ascites (32.36%), 44 cases of multiple granulomas in the colon (2.61%), and 29 cases of dwarf (1.72%). Most of the patients were old and 51.72% of them were more than 60 years old. A total of 1 331 patients (79.04%) needed treatment and assistance at present, and 36.44% of them who had ascites needed internal medicine treatment.CONCLUSION:There are also many patients with advanced schistosomiasis in Sichuan Province, and ascites and splenomegaly (post-surgery) were the main types. The patients with ascites should be the important objects of the treatment and assistance in the future.

OBJECTIVE:To evaluate the effect of Ecological Civilized Homestead Construction on schistosomiasis control.METHODS:The data of ecological civilized homestead construction and schistosomiasis control were collected and analyzed in Meiwan Village, Shuangqiao Town, Danling County, Sichuan Province from 2004 to 2010.RESULTS:Ecological Civilized Homestead Construction was carried out from 2004 to 2010. Totally 454 bio-gas pools were built. All the farmers used well water. The popularized rates of the household bio-gas pool, sanitary toilet, sewage treatment pool reached 100%. The number of cattle was 4, which decreased by 91.30% compared with that in 2004, and all the cattle were fed in captivity. The schistosome infection rates of populations were 0.26% and 0.30% in 2005 and 2008, respectively, and nobody was infected in other years. The infection rate of cattle was 0 from 2004 to 2010. The awareness rate of knowledge about schistosomiasis control achieved 100% in the population over 6 years old. Most of the farmers could use certain protective measures while they were farming.CONCLUSION:The effect of ecological civilized homestead construction on schistosomiasis control is remarkable.