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Schistosomiasis is a public health problem mostly in Africa. In 2014, World Health Organization (WHO) signed a tripartite memorandum of understanding (MOU) with China and Tanzania-Zanzibar paving the way for piloting interventions for schistosomiasis elimination in Zanzibar. The study has been designed including the transmission pattern of schistosomiasis; the effectiveness studies of praziquantel from China and mass drug administration (MDA) for suitable method of human treatment; biological study of snails and effectiveness of novel molluscicides from China in laboratory and field for the suitable method of snail control; KAP study and health education design for suitable method of behavior interventions by health education. The integrated measures will be implemented after baseline surveillance. At last, the effectiveness of the integrated measure will be evaluated by the index of snail density, prevalence, and KAP of human.

Being a zoonotic parasitic disease, schistosomiasis was widely spread in 12 provinces of Southern China in the 1950s, severly harming human health and hindering economic development. The National Institute of Parasitic Diseases at the Chinese Center for Diseases Control and Prevention, and Chinese Center for Tropical Diseases Research (NIPD-CTDR), as the only professional institution focussing on parasitic diseases at the national level, has played an important role in schistosomiasis control in the country. In this article, we look back at the changes of schistosomiasis endemicity and the contribution of NIPD-CTDR to the national schistosomiasis control programme. We review NIPD-CTDR's activities, including field investigations, design of control strategies and measures, development of diagnostics and drugs, surveillance-response of endemic situation, and monitoring & evaluation of the programme. The NIPD-CTDR has mastered the transmission status of schistosomiasis, mapped the snail distribution, and explored strategies and measures suitable for different types of endemic areas in China. With a good understanding of the life cycle of Schistosoma japonicum and transmission patterns of the disease, advanced research carried out in the NIPD-CTDR based on genomics and modern technology has made it possible to explore highly efficient and soft therapeutic drugs and molluscicides, making it possible to develop new diagnostic tools and produce vaccine candidates. In the field, epidemiological studies, updated strategies and targeted intervention measures developed by scientists from the NIPD-CTDR have contributed significantly to the national schistosomiasis control programme. This all adds up to a strong foundation for eliminating schistosomiasis in China in the near future, and recommendations have been put forward how to reach this goal.

Despite significant progress, China faces the challenge of re-emerging schistosomiasis transmission in currently controlled areas due, in part, to the presence of a range of animal reservoirs, notably water buffalo and cattle, which can harbor Schistosoma japonicum infections. Environmental, ecological and social-demographic changes in China, shown to affect the distribution of oncomelanid snails, can also impact future schistosomiasis transmission. In light of their importance in the S. japonicum, lifecycle, vaccination has been proposed as a means to reduce the excretion of egg from cattle and buffalo, thereby interrupting transmission from these reservoir hosts to snails. A DNA-based vaccine (SjCTPI) our team developed showed encouraging efficacy against S. japonicum in Chinese water buffaloes. Here we report the results of a double-blind cluster randomized trial aimed at determining the impact of a combination of the SjCTPI bovine vaccine (given as a prime-boost regimen), human mass chemotherapy and snail control on the transmission of S. japonicum in 12 selected administrative villages around the Dongting Lake in Hunan province. The trial confirmed human praziquantel treatment is an effective intervention at the population level. Further, mollusciciding had an indirect ~50% efficacy in reducing human infection rates. Serology showed that the SjCTPI vaccine produced an effective antibody response in vaccinated bovines, resulting in a negative correlation with bovine egg counts observed at all post-vaccination time points. Despite these encouraging outcomes, the effect of the vaccine in preventing human infection was inconclusive. This was likely due to activities undertaken by the China National Schistosomiasis Control Program, notably the treatment, sacrifice or removal of bovines from trial villages, over which we had no control; as a result, the trial design was compromised, reducing power and contaminating outcome measures. This highlights the difficulties in undertaking field trials of this nature and magnitude, particularly over a long period, and emphasizes the importance of mathematical modeling in predicting the potential impact of control intervention measures. A transmission blocking vaccine targeting bovines for the prevention of S. japonicum with the required protective efficacy would be invaluable in tandem with other preventive intervention measures if the goal of eliminating schistosomiasis from China is to become a reality.

Despite sustained efforts for its control made over the past 50+ years, the re-emergence of schistosomiasis in China was noted around the turn of the new millennium. Consequently, a new integrated strategy was proposed to stop the contamination of schistosome eggs to the environment, which emphasizes health education, access to clean water and adequate sanitation, mechanization of agriculture and fencing of water buffaloes, along with chemotherapy. Validation of this integrated control strategy in four pilot counties in the provinces of Anhui, Hubei, Hunan and Jiangxi revealed significant reductions in the rate of Schistosoma japonicum infection in humans and intermediate host snails. Importantly, this strategy showed an impact on diseases beyond schistosomiasis, signified by concomitant reductions in the prevalence of soil-transmitted helminth infections. In view of China's new integrated strategy for transmission control of schistosomiasis showing an ancillary benefit on other helminthic diseases, we encourage others to investigate the scope and limits of integrated control of neglected tropical diseases.

Background Schistosoma japonicum causes an infection involving humans, livestock, and snails and is a significant cause of morbidity in China. Methods We evaluated a comprehensive control strategy in two intervention villages and two control villages along Poyang Lake in the southeastern province of Jiangxi, where annual synchronous chemotherapy is routinely used. New interventions, implemented from 2005 through 2007, included removing cattle from snail-infested grasslands, providing farmers with mechanized farm equipment, improving sanitation by supplying tap water and building lavatories and latrines, providing boats with fecal-matter containers, and implementing an intensive health-education program. During the intervention period, we observed changes in S. japonicum infection in humans, measured the rate of infection in snails, and tested the infectivity of lake water in mice. Results After three transmission seasons, the rate of infection in humans decreased to less than 1.0% in the intervention villages, from 11.3% to 0.7% in one village and from 4.0% to 0.9% in the other (P

Although the number of human infections decreased, human prevalence increased from 4.9% in 1995 to 5.1% in 2004., Results from the third nationwide cluster sampling survey on the epidemiology of schistosomiasis in the People’s Republic of China, conducted by the Ministry of Health in 2004, are presented. A stratified cluster random sampling technique was used, and 239 villages were selected in 7 provinces where Schistosoma japonicum remains endemic. A total of 250,987 residents 6–65 years of age were included in the survey. Estimated prevalence rates in the provinces of Hunan, Hubei, Jiangxi, Anhui, Yunnan, Sichuan, and Jiangsu were 4.2%, 3.8%, 3.1%, 2.2%, 1.7%, 0.9%, and 0.3%, respectively. The highest prevalence rates were in the lake and marshland region (3.8%) and the lowest rates were in the plain region with waterway networks (0.06%). Extrapolation to all residents in schistosome-endemic areas indicated 726,112 infections. This indicates a reduction of 16.1% compared with a nationwide survey conducted in 1995. However, human infection rates increased by 3.9% in settings where transmission is ongoing.

To evaluate the schistosomiasis control effect of the measures of replacing cattle with machine for cultivation and forbidding depasturage of livestock on marshlands in marshland and lake regions.The retrospective review and field survey were implemented in the Jiangling and Gongan counties of Hubei Province where were implemented with the measure of replacing cattle with machine for cultivation, and Yuanjiang and Huarong counties of Hunan Province where were implemented with the measure of forbidding the depasturage of livestock on marshlands. The schistosome infection status of human, cattle, and Oncomelania hupensis snails, and schistosome-infested field excreta were surveyed from 2007 to 2013. The effects of the interventions were compared before and after their implementations.The 6 villages of Hubei Province were implemented with the measure of replacing cattle with machine for cultivation, and 7 villages of Hunan Province were implemented with the measure of forbidding the depasturage of livestock on marshlands. From 2007 to 2013, the schistosome infection rates of residents declined from 3.95% to 0.70% (χ2 = 128.376, P0.05), with the descend range of 82.53%. The descend ranges of the measures of replacing cattle with machine for cultivation and forbidding the depasturage of livestock on marshlands were 83.081% and 81.62% respectively, and there was no significant difference between the two measures (χ2 = 0.132, P0.05). The infection rate of cattle decreased from 3.66% in 2007 to 0.65% in 2013, and the descend range was 82.24% (χ2 = 13.692, P0.05). The field excreta was surveyed in the snail breeding place in 2013. The investigated area was 157.435 hm2, and 625 samples of field feces of cattle were collected with the density of field excreta of 3.97/hm2, and the positive rate was 1.12% (7/625). The schistosome infection rate of snails and the density of infected snails decreased successively from 2007, and no infected snails were detected from 2011 to 2013.The schistosomiasis endemic situation are decreased significantly after the interventions of replacing cattle with machine for cultivation and forbidding the depasturage of livestock on marshlands. Therefore, schistosomiasis control effect of these measures is notable in the marshland and lake regions.

Schistosomiasis japonica is a zoonosis of major public health importance in southern China. We undertook a drug intervention to test the hypothesis that buffalo are major reservoirs for human infection in the marshlands/lake areas, where one million people are infected. We compared human and buffalo infection rates and intensity in an intervention village (Jishan), where humans and buffalo were treated with praziquantel, and a control village (Hexi), where only humans were treated, in the Poyang Lake region. Over the four-year study, human incidence in Jishan decreased but increased in Hexi. Adjustment of incidence by age, sex, water exposure, year, and village further confirmed the decreased human infection in Jishan. Chemotherapy for buffaloes resulted in a decrease in buffalo infection rates in Jishan, which coincided with the reduction in human infection rates there in the last two years of the study. Mathematical modeling predicted that buffalo are responsible for 75% of human transmission in Jishan.

A U.S. National Institutes of Health-sponsored study was initiated in 1998, ending in 2002, to examine the hypothesis that bovines, buffaloes in particular, were responsible for the persistence of schistosomiasis in human populations living in and around Poyang Lake, Jiangxi Province, P. R. China. The two villages are the focus of this paper, the experimental Jishan Village and the control Hexi Village. The prevalence and intensity of infection of humans and buffaloes were determined. Then, all inhabitants of all the villages were treated with praziquantel, while only the buffaloes of the experimental (intervention) village were treated. Following treatment, rates of reinfection of people in the two villages and buffaloes in the experimental village, as well as the ongoing prevalence of infections in the buffaloes of the control village were monitored annually. Quantitative collections of snails were made pre- and post-flood for a total of nine seasons to determine the density of snails, density of infect...

To analyze the time and space aggregation of acute schistosome infections in marshland and lake areas in five provinces (Jiangsu, Anhui, Jiangxi, Hubei and Hunan province) from 2005 to 2012, so as to provide the evidence for establishing control strategies and taking effective control measures.The data of patients with acute schistosome infection in marshland and lake areas in five provinces from 2005 to 2012 were collected and analyzed with the concentration ratio and circular distribution methods for the epidemic season features and time aggregation of the infection, and with the spatial autocorrelation analysis for the space aggregation of the infected cases.According to the concentration ratio, the occurrence of acute schistosome infection had strong seasonality, and the concentration ratio was 0.758; according to the circular distribution method, the peak day of acute schistosome infections was 10th, August. The spatial analysis suggested that the infected cases highly gathered around Poyang Lake, Dongting Lake and Yangtze River Basin in 23 counties of the five provinces, and the result of spatial autocorrelation analysis showed that the spatial autocorrelation index I was 0.16 (P = 0.01).The occurrence of acute schistosome infections in lake regions of the 5 provinces shows strong seasonality and space aggregation, therefore we can bring the control mark forward, and take targeted prevention and control measures in high aggregation areas of acute schistosomiasis.

Schistosomiasis remains an important public health issue, with a large number of cases reported across sub-Saharan Africa, and parts of Asia and Latin America. China was once highly endemic, but has made substantial progress and is moving towards elimination of schistosomiasis. Meanwhile, despite long-term, repeated, school-based chemotherapy in many African countries, more than 90% of all schistosomiasis cases are concentrated in Africa, and hence, this continent constitutes the key challenge for schistosomiasis control. Opportunities and issues for international collaboration in the fight against schistosomiasis are outlined with a focus on China's experiences, including the role of public health authorities and intersectoral collaboration, use of new and effective snail control approaches and diagnostic tools adapted to the specific stage of control, as well as the strengthening of risk mapping and surveillance-response mechanisms. Training courses targeting African governmental officials and professionals, coupled with field visits of African scientists and control programme managers to China, and vice versa, are considered important for improved schistosomiasis control and elimination. The crucial question remains whether the Chinese experience can be translated and applied in African countries to improve the effectiveness of health interventions and scale-up.

Background Despite significant, steady progress in schistosomiasis control in the People's Republic of China over the past 50 years, available data suggest that the disease has re-emerged with several outbreaks of acute infections in the early new century. In response, a new integrated strategy was introduced. Methods This retrospective study was conducted between Jan 2005 and Dec 2012, to explore the effectiveness of a new integrated control strategy that was implemented by the national control program since 2004. Results A total of 1,047 acute cases were recorded between 2005 and 2012, with an annual reduction in prevalence of 97.7%. The proportion of imported cases of schistosomiasis was higher in 2011 and 2012. Nine clusters of acute infections were detected by spatio-temporal analysis between June and November, indicating that the high risk areas located in the lake and marshland regions. Conclusion This study shows that the new integrated strategy has played a key role in reducing the morbidity of schistosomiasis in the People's Republic of China., Author Summary A retrospective study on the incidence of acute schistosomiasis in the People's Republic of China (P.R. China) was performed, in order to assess the new integrated control strategy that was implemented through the national control program from 2005 to 2012. The lake and marshland regions have been identified as high risk areas as shown by the nine spatio-temporal clusters that we found in the transmission period between June and November each year. When a total of 1,047 reported cases of acute schistosomiasis were analyzed, a reduction in prevalence of 97.7% between 2005 and 2012 was found. In contrast, imported cases of acute schistosomiasis increased between 2011 and 2012. These findings support the approach and effectiveness of the new integrated strategy in the reduction of schistosomiasis morbidity.

Despite major successes in its control over the past 50years, schistosomiasis japonica continues to be a public health problem in the People's Republic of China (P.R. China). Historically, the major endemic foci occur in the lakes and marshlands along the Yangtze River, areas where transmission interruption has proven difficult. The current endemic situation may alter due to the closure of the Three Gorges Dam. Considerable environmental and ecological changes are anticipated that may result in new habitats for the oncomelanid intermediate snail host of Schistosoma japonicum (Sj), thereby increasing the risk of transmission. The current national control program for P.R. China involves a multi-component integrated strategy but, despite targeting multiple transmission pathways, certain challenges remain. As the Chinese government pushes towards elimination, there is a requirement for additional tools, such as vaccination, for long-term prevention. Whereas the zoonotic nature of schistosomiasis japonica adds to the complexity of control, it provides a unique opportunity to develop a transmission blocking vaccine targeting bovines to assist in the prevention of human infection and disease. Mathematical modelling has shown that control options targeting the various transmission pathways of schistosomiasis japonica and incorporating bovine vaccination, mass human chemotherapy and mollusciciding could lead to its elimination from P.R. China. Here we present the study design and baseline results of a four-year cluster randomised intervention trial we are undertaking around the schistosomiasis-endemic Dongting Lake in Hunan Province aimed at determining the impact on schistosome transmission of the multi-component integrated control strategy, including bovine vaccination using a heterologous "prime-boost" delivery platform based on the previously tested SjCTPI vaccine.

This report showed the endemic status of schistosomiasis in P. R. China at national level in 2012. By the end of 2012, the total number of schistosomiasis japonica cases were estimated to be 240597, with a decrease of 16.12% compared with that in 2011. Meanwhile, thirteen acute cases were reported. Compared with 2011, 10.34% more advanced schistosomiasis patients were treated (22988) in 2012. Nationally, around 368741.67 hm2 were found to be infested with Oncomelania hupensis snails by the end of 2012, among which 46.71 hm2 were newly reported. Moreover, 1 189829 cattle were estimated to be raised in epidemic regions with 0.52% of them being infected with Schistosoma japonicum, which experienced a reduction of 23.53% compared with that in 2011.

This article expatiates the epidemiological characteristics, the evolution process of control and prevention strategies and measures in hilly regions with schistosomiasis endemic, especially the research progress and obstacle factors existed in the implementation process of the comprehensive strategy focused on controlling infection source, aiming at providing references for the hilly regions to reach transmission interrupted standard.

To establish the measures of schistosomiasis field survey and evaluate the efficacy of their application according to the content of indexes of rapid assessment system to high transmission risks in schistosomiasis endemic areas of lake regions.In 2012, based on the analysis of Oncomelania hupensis snail situation, and schistosomiasis epidemic data of human and cattle from 2008-2010, 60 villages from Hunan, Hubei, Jiangxi and Anhui provinces were selected and investigated, and the content of the investigation included the field feces, snail status, and epidemic situation of human and cattle. The systemic sampling was applied for snail investigation; the feces collected from snail investigation field were examined by the hatching test (3 bottles for 1 sample). A cluster random sampling was carried out with more than 300 people in each village. By using the hatching test (3 bottles for 1 sample) , the human stool examination was carried out for the identification of the infected persons who were positive in the immunity test screening. The hatching test was applied for cattle of all the villages (3 bottles for 1 sample).A total of 65 field feces spots were surveyed in 60 villages, field feces were found in 78.46% (51/65) of spots, and the positive rate of field feces was 1.07% (9/842). There were 73.33% (44,160)of villages with cattle, and the largest amount cattle with 329 was found in Wufeng Village, Jiangxi Province. The cattle infection rate was 1.5 1% (4,913,242) in 3242 investigated cattle. The highest cattle infection rate was 4% in Tongxin Village, Jiangxi Province. The population of 47 099 was surveyed, the infection rate was 0.77% (364/47 099), and the highest was 4.37% in Xumuchang Village, Hunan Province. The infection rate was 0 in 43.33% (26/60) of villages. No acute schistosomiasis cases were reported in all the villages in 2011 and 2012. Totally, 77 snail spots in 60 villages were investigated, and 51 spots were marshland and 26 spots were ditches. The schistosome-infected snails were detected in 5.88% (3/51 )of the marshland spots and the living snails were found in 80.39%(41/51) of the spots. The highest density of living snails was 3.20/0.1 m2 in Xumuchang Village, Hunan Province. The average density of infected snails was 0.00045/0.1 m2 (4/8942). The infected snail spots were distributed in Liujiadi Village and Liuhe Village of Hubei Province, and Jiangkou Village of Anhui Province. No infected snails were detected in 26 ditches spots. The living snails were detected in 53.85% (14/26) of the ditches spots. The highest average density of living snails was 3.76/0.1 m2 in Huakou Village, Hubei Province.The measures of field survey for rapid assessment system of high transmission risks in schistosomiasis endemic areas of lake regions are established and applied with scientific, impersonal and rapid characteristics.

We hypothesize that bovine infections are responsible for the persistence of human schistosomiasis transmission in the Yangtze marshlands of China. To test this hypothesis, we are carrying out a comparative intervention among four administrative villages in the Poyang Lake region, Jiangxi Province, two of which are experimental and two are control. The primary design involves treating, at the onset of the study, all the inhabitants in all four villages with praziquantel and all the bovines in two villages (the experimental or intervention villages). Following treatment, rates of reinfection in people of all villages, and in bovines in the experimental villages, will be assessed as will the ongoing prevalence of infection in bovines in the control villages. Before treatment, the prevalence and intensity of infection among humans and bovines was ascertained in the four villages. Our study design and baseline information are presented here, along with a description of the ecology of the study villages.

Schistosomiasis japonica remains a significant public-health problem in China. This study evaluated cost-effectiveness of a comprehensive schistosomiasis control program (2003–2006). The comprehensive control program was implemented in Zhangjia and Jianwu (cases); while standard interventions continued in Koutou and Xiajia (controls). Incurred costs were documented and the schistosomiasis comprehensive impact index (SCI) and cost-effectiveness ratio (Comprehensive Control Program Cost/SCI) were applied. In 2003, prevalence of Schistosoma japonicum infection was 11.3% (Zhangjia), 6.7% (Jianwu), 6.5% (Koutou), and 8.0% (Xiajia). In 2006, the comprehensive control program in Zhangjia and Jianwu reduced infection to 1.6% and 0.6%, respectively; while Koutou and Xiajia had a schistosomiasis prevalence of 3.2% and 13.0%, respectively. The year-by-year SCIs in Zhangjia were 0.28, 105.25, and 47.58, with an overall increase in cost-effectiveness ratio of 374.9%–544.8%. The SCIs in Jianwu were 16.21, 52.95, and 149.58, with increase in cost-effectiveness of 226.7%–1,149.4%. Investment in Koutou and Xiajia remained static (US$10,000 unit cost). The comprehensive control program implemented in the two case villages reduced median prevalence of schistosomiasis 8.5-fold. Further, the cost effectiveness ratio demonstrated that the comprehensive control program was 170% (Zhangjia) and 922.7% (Jianwu) more cost-effective. This work clearly shows the improvements in both cost and disease prevention effectiveness that a comprehensive control program-approach has on schistosomiasis infection prevalence.

To establish an index system for rapid assessment of environment with high transmission risk of schistosomiasis in marshland and lake regions.The alternative indices were established preliminarily by the documentary method, and then the Delphi method was used two rounds to select the indices and establish the index system. The degree of familiar and authority of the experts as well as the weights of all indices were assessed.A total of 3 primary indices namely morbidity in domestic animals, morbidity in humans and Oncomelania snail status were established, among which the weight of morbidity in domestic animals (0.68) was the highest. Totally 16 secondary indices were established, among which the combinative weights of the positive rate of wild feces (0.09), the infection rate of livestock (0.09), the infection rate of humans (0.07), the number of cases with acute schistosomiasis (0.07), the area with infected snails (0.07), and the density of infected snails (0.07) were the highest. The coefficients of familiar degree and authority degree of the experts of the primary indices were 0.79-0.85 and 0.88-0.91, and those of the secondary indices were 0.68-0.86 and 0.77-0.91, respectively.The index system for rapid assessment of environment with high transmission risk of schistosomiasis in marshland and lake regions is established preliminarily. Using this system, we can assess the key endemic indices of humans, domestic animals and snails to understand the endemic situation in the investigated sites.

Schistosomiasis is a tropical disease, which could do serious damage to the people's health, and it hinders the development of the social economy but may be neglected. After a positive control, some countries and regions have blocked the spread of schistosomiasis. However, in the past few years, with the development of social economy, due to the global movement of people, schistosomiasis not only poses a threat to control areas, but also may cause new endemic areas. This article reviews the parasitological characteristics, clinical manifestations, epidemiological situation, and control approaches of three major kinds of human schistosomiasis, schistosomiasis japonica, schistosomiasis haematobia, and schistosomiasis mansoni.

To establish a scientific, objective and operational assessing system for schistosomiasis endemicity, so as to provide a scientific evidence for revising the current Criteria for Control and Elimination of Schistosomiasis in China (GB 15976-2006).A questionnaire was designed based on reference review and 20 scientists working in the field of schistosomiasis control, research or management were investigated by using the Delphi method. The importance of each index reflecting the endemicity of schistosomiasis was scored by each scientist. The assessing system for endemicity of schistosomiasis was established and the normalized weight and combined weight were calculated.The assessing system included three indices in the first grade and seven indices in the second grade. Among the indices in the first grade, the normalized weights of infection status of human beings, infection status of livestock, and Oncomelania snail's status were 0.360 2, 0.335 2, and 0.304 6, respectively. Among the indices in the second grade, the prevalence of livestock showed the highest combined weight of 0.335 2 while the infection rate of snails showed the lowest score of 0.093 3.The indexes of the assessing system for the endemicity of schistosomiasis established are reasonable, comprehensive, and authoritative, which provide the scientific evidence for revising the currently available Criteria for Control and Elimination of Schistosomiasis in China.

To understand the endemic situation of schistosomiasis among 81 national surveillance sites in China in 2011.The data of the Oncomelania snail status, schistosomiasis in residents and domestic animals, and other relevant factors were collected and analyzed for the epidemic characteristics and changes in different areas in the 81 national surveillance sites in 2011.Among the 81 national surveillance sites, the average positive rate of residents with serum examinations and the average infection rate of the residents were 7.78% and 0.54%, respectively, and the infection rate of domestic animals was 0.97% in 2011, which all decreased compared with the rates of 2010. The area of infected snail habitats was 98.30 hm2. The mean densities of living snails and infected snails were 0.222 6 snails/0.1 m2 and 0.000 3 snails/0.1 m2, respectively. The infection rate of snails was 0.14%. The number of domestic animals opened on areas with snails was 12 422, which increased by 46.99% compared with that in 2010.The endemic situation of schistosomiasis improves in 2011 compared with that in 2010. However, the improvement is not great. Therefore, the management of domestic animals as the major infectious source should be further strengthened.

To analyze the impact of large hydraulic projects on schistosomiasis transmission and evaluate the transmission risk in potential endemic areas.During 2008-2010, surveillance on risk factors related to schistosomiasis transmission and risk assessment were carried out in potential endemic sites in counties of Xuyu, Hongze, Jinhu, and Gaoyou in Jiangsu Province, Weishan County in Shangdong, Qianjiang City and Yiling District of Yichang City in Hubei, Juchao District of Chaohu City in Anhui Province, Wanzhou and Kaixian in Chongqing in Three Gorges Dam region or passed by South-to-North Water Diversion Project and Zhangjiagang City in Jiangsu Province located in lower reach of Yangtze River. At least one fixed and three temporary monitoring sites were set in each county (city or district). Local inhabitants aged 6-65 years old were screened by indirect haemagglutination assay (IHA) or ELISA, and the sero-positives were tested by Kato-Katz or miracidium hatching techniques to investigate possible infection in 2008. The endemic status of schistosomiasis in mobile population was surveyed every year during 2008-2010. Infection status in livestocks was surveyed in Juchao, Qianjiang, Gaoyou and Wanzhou Counties in 2008-2010. Oncomelania hupensis distribution was investigated in risky and suspicious areas. Snail spreading investigation was conducted through salvaging floater and snails-inducing by straw curtains in rivers connected with Yangtze River.8 256 local inhabitants were investigated by serological tests with a positive rate of 0.7% (60/8 256). Among the 60 serologically positive subjects, 55 individuals were examined by stool examination but none of them was egg positive. The antibody prevalence rate of migrating population in 2008-2010 was 2.0%, 1.4%, and 1.7%, respectively, with no significant difference (chi2 = 3.57, P0.05). Among the serologically positive subjects, egg-positive cases were found in migrating population in Juchao District each year and one case was found in Jinhu County in 2010. Oncomelania snails were only found in in Jinhu and Gaoyou without infected ones. A lot of aquatic shell-fish and snails were collected in the water floater and straw curtain without Oncomelania snails.Schistosomiasis is not endemic in the original nonendemic areas in Three Gorges Dam region and areas passed by South-to-North Water Diversion Project until now, but potential risk of transmission exists. Long term surveillance scheme on schistosomiasis should be established with varied monitoring factors in different category areas.

Diseased animals are the main source of infection of schistosomiasis. River beach wild fecal contamination is the direct risk factor for schistosomiasis transmission, and the river beach contamination index has important significance in the schistosomiasis monitoring. This paper reviews the river beach wild fecal contamination to the identification and evaluation of the risk of schistosomiasis transmission.

To investigate and analyze the schistosomiasis endemic status and influencing factors in areas of schistosomiasis transmission control in hilly regions of mountain areas, so as to provide the reference for establishing the strategy and measures to achieve the target of schistosomiasis transmission-interrupted in the similar areas.Dongpo District of Meishan City, Sichuan Province, which was appropriate to the standards of schistosomiasis transmission controlled by national evaluation in 2008, was selected as a study area. The data of schistosomiasis control from 2008 to 2010 were collected. A survey for epidemiological factors was carried out from April to November in 2011. The survey of Oncomelania snails was performed with the systematic sampling combined with environmental method. The schistosome infection status of residents was investigated by the seroimmunological test and fecal hatching examination. The schistosome infection status of cattle was investigated by the plastic cup with top tube hatching method. The infested water contact of residents was investigated with questionnaire. At the same time, in 2011, a simple random sampling combined with rapid field assessment method was used to investigate the distribution of outdoor feces, outdoor feces containing schistosome eggs, snails and infected snails in two spots of Jingyang District, Deyang City and Renshou County, Meishan City which had been appropriate to the standards of schistosomiasis transmission controlled in 2006 and 2007 respectively.From 2008 to 2010, 182.6 thousand-213.3 thousand local residents were examined in Dongpo District, the positive rate of sero-immunological tests of population was 6.30% - 6.81%, and the infection rate of population was 0.02% -0.07% by estimated calculation. Totally 2 835-7 260 heads of cattle were examined and no positive cases were found. The areas of snail habits were 190.00-232.00 hm2, the intensities of living snails were 0.02-0.19 snails/0.1 m2, and no infected snails were found. In 2011, totally 204.4 thousand residents were examined and the positive rate of sero-immunological tests of population was 4.98% but no positive cases were founded through the parasitological tests. A total of 1 735 heads of cattle were examined and no positive cases were found. The areas of snail habits were 99.00 hm2, the intensity of living snails was 0.18 snails/ 0.1 m2, and no infected snails were found. Questionnaire analyses of a total of 537 residents in 4 villages showed that ditch, channel, pond, and paddy field were the major environments of the infested water contact of the residents. In the ditches and paddy fields, the average annual median values of water contact of residents were 15 and 20 person-times respectively before the area was appropriate to the standards of schistosomiasis transmission controlled, and 20 and 30 person-times respectively after the area was appropriate to the standards of schistosomiasis transmission controlled, and there were no significant differences (chi(ditch2) = 1.61, chi(padd field2) = 0.03, both P0.05). Whereas, in the channels and ponds, the average annual median values of water contact were 15 and 30 person-times respectively before the area was appropriate to the standards of schistosomiasis transmission controlled, but they were significantly reduced after the area was appropriate to the standards of schistosomiasis transmission controlled (chi(channel2) =10.35, chi(pond2) =18.69, both P0.01). In 2011, the rapid field investigation and assessment showed that the average appearance rates of snails through screening were 60.15% and 12.12% respectively in the 2 villages. The average densities of living snails were 1.19 snails/0.1m2 and 0.20 snails/0.1m2 respectively in the 2 villages, and there were no infected snails. A total of 78 outdoor feces of cattle and sheep were collected and the fecal hatching examinations showed that there were no positives.After the schistosomiasis endemic areas in hilly regions of mountain areas are appropriate to the standards of schistosomiasis transmission controll, the achievements have been consolidated. However, the potential schistosomiasis endemic factors still exist, such as the high positive rate of schistosome sero-immunological tests in population, frequently bovine flowing, and no obviously decrease of the snail area and density of living snails. Therefore, it is an urgent need to develop more suitable new technologies and measures to accelerate the process of schistosomiasis prevention and control.

The long-term effectiveness of the mainly chemotherapy-based control strategy of the World Bank Loan Project (WBLP) for schistosomiasis control in Chinese hilly and mountainous regions was evaluated with a view to determine the best road forward. Based on the national database of schistosomiasis prevalence for the periods of 1999-2001 and 2007- 2008 in the People's Republic of China, a Bayesian regression model was used for spatial comparison of schistosomiasis risk distribution between two periods taking account of all the potential risk factors simultaneously through two latent compo- nents of random effects: spatially correlated heterogeneities (CH) and spatially uncorrelated heterogeneities (UH). Four dif- ferent types of endemic areas were investigated: those that remained endemic despite control efforts (17 or 37.8%), those that became non-endemic (9 or 20.0%), those that reverted back to endemicity (7 or 15.6%), and those with fluctuating endemicity (12 or 26.7%). The overall prevalence of schistosomiasis was lower in 2007-2008 compared with that in 1999- 2001, but the spatial distribution of risk remained similar. Compared to 1999-2001, the magnitude and range of risk even tended to be greater in 2007-2008. UH showed a fluctuating pattern, while CH increased gradually doubling over the two periods. There was no evidence for long-term effectiveness of the WBLP chemotherapy-based control strategy in this region. Controlling the effect of UH is still the main aspect of current schistosomiasis control strategy for the hilly and mountain- ous regions, but innovative methods are urgently needed for effectively controlling UH.

To explore the approach and tool for surveillance and forecast of schistosomiasis, so as to provide scientific evidence for improving the sensitivity of the surveillance and forecast system of schistosomiasis.Two field detections were carried out in June and September by using the determination of sentinel mice in key high-risk water regions of 7 provinces of Hunan, Hubei, Jiangxi, Anhui, Jiangsu, Yunnan and Sichuan, and the sentinel mice were raised in laboratory and dissected for observation of schistosome infections. The database regarding schisosome infections in key water regions of China was established, and the tempo-spatial distribution and environmental features of the national surveillance and forecast sites with positive sentinel mice were analyzed.A total of 72 surveillance and forecast sites were detected in 34 counties (cities, districts) of 7 provinces. Of the 2 667 sentinel mice placed, 2 613 were recovered, with a recovery rate of 97.98%. Among the 72 sites detected, 17 were detected with positive sentinel mice, and the occurrence rate of positive sites was 23.61%. The occurrence rate was 17.24% (10/58) in June and 14.71% (10/68) in September, and no significant difference was observed between two batches (chi2 = 0.151, P = 0.698). Of the 2 436 sentinel mice dissected, 90 were positive, and 459 schistosome worms were collected, with a total infection rate of 3.69%, and the mean worm burdens of positive mice were 5.10 worms per mouse. The infection rate of sentinel mice was 2.82% (31/1 099) in June and 4.41% (58/1 337) in September, the infection rate of sentinel mice was significantly higher in September than that in Juen (chi2 = 14.681, P0.01), and the mean worm burdens of infected sentinel mice were 2.45 worms per mouse in June and 6.49 worms per mouse in September. The occurrence rates of the positive sites with infected snails detected in the study year, last year and without infected snails detected in recent 3 years were 29.63%, 41.67% and 12.12%, respectively, and no significant differences were detected (chi2 = 5.227, P = 0.071). The infection rates of sentinel mice in the aforementioned 3 settings were 9.38%, 3.98% and 0.59%, respectively, and there was significant difference observed (chi2 = 20.489, P0.01).The monitoring results of sentinel mice infections in key water regions can almost reflect the endemic situation of schistosomiasis in local areas. Notably, many infections are detected in settings without infected snails detected in recent years. The monitoring of sentinel mice infections could significantly improve the sensitivity of the surveillance and forecast system of schistosomiasis.

Based on the transmission status of schistosomiasis in People's Republic of China, the challenges and road map for achieving the transmission interruption of schistosomiasis by 2020 in the country was discussed, particularly focused on elimination strategy, surveillance and response approaches, and key technique needs in the three stages, e.g. pre-elimination, elimination and post-elimination stages. Recommendation of strengthening studies on transmission threshold and technological innovation at the low transmission level of schistosomiasis japonica were put forward.

Background The World Bank Loan Project (WBLP) for controlling schistosomiasis in China was implemented during 1992–2001. Its short-term impact has been assessed from non-spatial perspective, but its long-term impact remains unclear and a spatial evaluation has not previously been conducted. Here we compared the spatial distribution of schistosomiasis risk using national datasets in the lake and marshland regions from 1999–2001 and 2007–2008 to evaluate the long-term impact of WBLP strategy on China's schistosomiasis burden. Methodology/Principal Findings A hierarchical Poisson regression model was developed in a Bayesian framework with spatially correlated and uncorrelated heterogeneities at the county-level, modeled using a conditional autoregressive prior structure and a spatially unstructured Gaussian distribution, respectively. There were two important findings from this study. The WBLP strategy was found to have a good short-term impact on schistosomiasis control, but its long-term impact was not ideal. It has successfully reduced the morbidity of schistosomiasis to a low level, but can not contribute further to China's schistosomiasis control because of the current low endemic level. A second finding is that the WBLP strategy could not effectively compress the spatial distribution of schistosomiasis risk. To achieve further reductions in schistosomiasis-affected areas, and for sustainable control, focusing on the intermediate host snail should become the next step to interrupt schistosomiasis transmission within the two most affected regions surrounding the Dongting and Poyang Lakes. Furthermore, in the lower reaches of the Yangtze River, the WBLP's morbidity control strategy may need to continue for some time until snails in the upriver provinces have been well controlled. Conclusion It is difficult to further reduce morbidity due to schistosomiasis using a chemotherapy-based control strategy in the lake and marshland regions of China because of the current low endemic levels of infection. The future control strategy for schistosomiasis should instead focus on a snail-based integrated control strategy to maintain the program achievements and sustainably reduce the burden of schistosomiasis in China., Author Summary Schistosomiasis japonica is an important disease in China with a documented history of more than 2,100 years. The World Bank Loan Project (WBLP) implemented during 1992–2001 contributed greatly to China's schistosomiasis control. This study shows that the long-term impact of WBLP strategy on schistosomiasis control was not ideal. It can only maintain the morbidity of schistosomiasis at a low level, but can not reduce it further. Also, the WBLP strategy could not effectively compress the spatial distribution of schistosomiasis risk. To achieve further reductions in schistosomiasis-affected areas, and for sustainable control, focusing on controlling the intermediate host snail in the lake and marshland regions was suggested to be the next step to interrupt schistosomiasis transmission within the two most affected regions surrounding the Dongting and Poyang Lakes. While in the lower reaches of the Yangtze River, the WBLP's morbidity control strategy may need to continue for some time until snails in the upriver provinces have been well controlled.

Based on the objective of long- and mid-term development program for schistosomiasis control in China, the paper presents an analysis of strategy for schistosomiasis control and its function in the 12th Five-Year Plan. Meanwhile, the strategy and key elements of schistosomiasis control for recent years are put forward for different endemic areas.

To understand the migration regulation, knowledge of schistosomiasis control and infection status of migrant population in mountainous regions.Migrants from history heavy endemic villages of schistosomiasis were selected by the convenience sampling method, then they were investigated by questionnaire and fecal examination.A total of 884 migrants were investigated, the infection rate was 2.49%, and the awareness rate of knowledge on schistosomiasis control was 43.94%. Most of the migrant places were in schistosomiasis endemic areas, and those who accepted the examination and treatment of schistosomiasis accounted for a low percentage. The compliance rate of schistosomiasis examinations and treatment of migrant population was low. The general time of returning hometown was around the Chinese Spring Festival.As one of the key population of schistosomiasis control, the control work on migrants should be strengthened.

To detect the schistosomiasis clusters in marshland and lake areas in 2008, so as to provide the reference for schistosomiasis control and the methodology for detection of cluster areas of related diseases.SaTScan was used to detect the schistosomiasis clusters based on the spatial database from GIS and related variables, including the number of current patients and population in endemic areas.A total of 5 clusters including 39 counties (districts) were detected by SaTScan, the RRs and the Log-likelihood ratios of 3 clusters among them were over 3 and 1 000 (P0.05), respectively. The one with the highest RR and Log-likelihood ratio was located in the boundary of Hubei and Hunan provinces, and the cluster range there was the biggest. From there to the downstream of the Yangtze River, the area and RRs of the 5 clusters became smaller and smaller.The 5 provinces in the marshland and lake areas are still the key spatial clusters of schistosomiasis, especially near the boundary of Hubei and Hunan provinces.

To understand the conditions of schistosomiasis laboratories at county level, so as to supply the information for diagnostic capacity building.A questionnaire survey was conducted at 40 random selected counties which were in charge of national surveillance for schistosomiasis. The information of staffs, areas of laboratories, equipment configuration and diagnostic methods from each laboratory were collected. The serum specimens and Kato-Katz thick smears from the national surveillance sites were randomly selected and retested by provincial staffs to evaluate the testing ability of the personnel.The average age of laboratory staffs was 40.93 +/- 9.56 years old, 69.39% of staffs were older than 35 years, 86.22% of them had education background below bachelor degree. Except missed professional titles of 4 persons, the staffs with primary, middle and high professional titles accounted for 56.63%, 39.29% and 2.04%, respectively. The laboratory areas varied greatly while independent schistosomiasis stations had the lowest areas with 52.81 +/- 40.08 m2, and the equipment configurations of laboratories were in a low level. The consistency rates of primary test and reexamination for serum specimens and thick smear slides were 95.89% and 99.53%, respectively, with the Kappa value over 0.90. Nine immunodiagnostic kits were used in these laboratories, and Kato-Katz technique and miracidium hatching technique were the main parasitological methods.The personnel structure of laboratories at primary prevention and treatment facilities for schistosomiasis is unreasonable, while the basic infrastructure of laboratories is backward and the use of diagnostic assays/methods is disordered. The diagnostic capacity building should be strengthened, and the construction and management of schistosomiasis laboratories should be standardized.

The surveillance network of schistosomiasis in China can be roughly divided into three parts, namely repetitive cross-sectional sample survey, regional surveillance, and fixed longitudinal surveillance. The result of the network provides an important basis for decision-making to realize the endemic situation of schistosomiasis, to develop and evaluate the control planning and its effects in various stages. However, there still exist some problems in the surveillance network of schistosomiasis, such as relatively backward of the surveillance technology, low utilization of data, lack of an effective monitoring network evaluation system and so on. With the advances in socio-economic and technology, the surveillance network of schistosomiasis will develop from a single integrated disease surveillance towards a multi-disciplines surveillance, and gradually establish an efficient and timely surveillance system integrating early warning and multi-disciplines surveillance after the establishment and improvement of real-time reports and other basic information platform.

Background Appropriate diagnostics to monitor disease trends and assess the effectiveness and impact of interventions are essential for guiding treatment strategies at different thresholds of schistosomiasis transmission and for certifying elimination. Field validation of these assays is urgently needed before they can be adopted to support policy decisions of the national programme for control and elimination of schistosomiasis in P.R. China. We compared the efficacy and utility of different immunoassays in guiding control strategies and monitoring the endemic status of S. japonicum infections towards elimination. Methodology/Principal Findings A cross-sectional survey was conducted in seven villages with different transmission intensities settings to assess the performance and utility of three immunoassays, e.g., an indirect hemagglutination assay (IHA_JX), an enzyme linked immunosorbent assay (ELISA_SZ), and a dot immunogold filtration assay (DIGFA_SH). 6,248 individuals aged 6–65 years old who gave consent and supplied their stool and blood samples were included for data analysis. Results showed that ELISA_SZ performed significantly higher sensitivity (95.45%, 95%CI: 92.94–97.97%) than IHA_JX (87.59%, 95%CI: 83.51–91.49%) and DIGFA_SH (79.55%, 95%CI: 74.68–84.41%), especially in subgroups with very low infection intensity. The specificity of ELISA_SZ, IHA_JX, DIGFA_SH in 6–9 year olds with occasional exposure was nearly 90%. DIGFA_SH performed the highest screening efficacy for patients among three assays with overall positive predicative value of 13.07% (95%CI: 11.42–14.72%). We found a positive correlation of antibody positive rate of IHA_JX with results of stool examination in age strata (r = 0.70, P, Author Summary Immunodiagnostic assays are widely applied in the field to control schistosomiasis in P.R. China as the prevalence and infection intensity of schistosome infections decrease. Field evaluations are urgently needed before they can be adopted to support policy decisions of the national programme for the control and elimination of schistosomiasis in P.R. China. We carried out a large scale cross-sectional survey in field settings with different transmission situations to validate immunodiagnostic tools that can be used to formulate new schistosomiasis elimination strategy in P.R. China. Regarding stool examination as gold reference, the validity and screening efficacy of each immunodiagnostic kit were calculated and compared with each other. The association of the prevalence of schistosomiasis and antibody positive rates determined by immunoassays were analyzed using Pearson's correlation coefficient values. The study indicates that which test to use with the elimination strategy is dependent on the purpose of testing, the endemic status of community and the resources available. And more sensitive methods need to be explored and used to target infected individuals for treatment or to eliminate schistosomiasis.

Background Schistosoma japonicum is a major public health concern in the Peoples' Republic of China (PRC), with about 800,000 people infected and another 50 million living in areas at risk of infection. Based on ecological, environmental, population genetic and molecular factors, schistosomiasis transmission in PRC can be categorised into four discrete ecosystems or transmission modes. It is predicted that, long-term, the Three Gorges Dam (TGD) will impact upon the transmission of schistosomiasis in the PRC, with varying degree across the four transmission modes. Methodology/Principal Findings We undertook longitudinal surveillance from 2002 to 2006 in sentinel villages of the three transmission modes below the TGD across four provinces (Hunan, Jiangxi, Hubei and Anhui) to determine whether there was any immediate impact of the TGD on schistosomiasis transmission. Eight sentinel villages were selected to represent both province and transmission mode. The primary end point measured was human incidence. Here we present the results of this five-year longitudinal cohort study. Results showed that the incidence of human S. japonicum infection declined considerably within individual villages and overall mode over the course of the study. This is also reflected in the yearly odds ratios (adjusted) for infection risk that showed significant (P, Author Summary Schistosomiasis, caused by Schistosoma japonicum, is a significant parasitic disease and public health problem in China. How the parasite is transmitted there can be categorized into four distinct modes (modes I–IV) and it is predicted that the Three Gorges Dam, recently completed, will affect the way schistosomiasis is spread in these modes. We monitored transmission for a 5-year period (2002–2006) in eight villages, representative of the three modes (I–III) below the dam across four provinces (Hunan, Jiangxi, Hubei and Anhui) to determine whether there was any immediate impact of the dam on schistosomiasis spread. Human schistosomiasis incidence declined considerably within individual villages and each mode, and the yearly odds ratios (adjusted) for infection risk showed significant downward trends in all three modes over the follow-up period. The decreased human S. japonicum incidence recorded across transmission modes I–III was probably attributable to annual human and bovine praziquantel drug treatment. If an increase in schistosome transmission had occurred as a result of the dam, it would be of negligible size compared with this treatment-induced decline. There had thus been virtually no immediate impact of the TGD on schistosomiasis transmission downstream of the dam over the 5-year surveillance period.

Background The dipstick dye immunoassay (DDIA), recently commercially available in the People's Republic of China (P.R. China), is a rapid and simple test to detect human antibodies against Schistosoma Japonicum. Its performance and utility for screening schistosome infection in low endemic areas is little known. We therefore carried out a cross-sectional survey in seven villages with low endemicity of schistosomiasis in P.R. China and assessed the performance and utility of DDIA for diagnosis of schistosomiasis. Stool samples were collected and examined by the Kato-Katz method and the miracidium hatching technique. Serum samples, separated from whole blood of participants, were tested by DDIA. Results 6285 individuals aged 6-65 years old participated in this study, with a prevalence of schistosomiasis of 4.20%. Using stool examination as a gold reference standard, DDIA performed with a high overall sensitivity of 91.29% (95% CI: 87.89-94.69%) and also a high negative predictive value, with a mean value of 99.29% (95% CI: 98.99-99.58%). The specificity of DDIA was only moderate (53.08%, 95% CI: 51.82-54.34%). Multivariate analysis indicated that age, occupation and history of schistosome infection were significantly associated with the false positive results of DDIA. Conclusions DDIA is a sensitive, rapid, simple and portable diagnostic assay and can be used as a primary approach for screening schistosome infection in areas of low endemicity. However, more sensitive and specific confirmatory assays need to be developed and combined with DDIA for targeting chemotherapy accurately.

To detect and analyze the clusters of schistosomiasis on marshland and lake areas based on geographic information system (GIS) in 2008 and to provide suggestions for the development of integrated methodology on the detection of clusters on related diseases.Moran's I of global spatial autocorrelation, Getis-Ord Gi of local spatial autocorrelation and SaTScan were used to detect the schistosomiasis clusters based on GIS and comparison of the results for different methods were performed.Results from the global Moran's I tests for all the marshland and lake areas related to the schistosomiasis were statistically significant (P0.05) and indicated spatial heterogeneity;the z-score outcomes as calculated by Getis-Ord Gi indicated high cluster that 50 clusters were categorized at the 0.05 significance level and the z-score of these 45 clusters were more than 0. Results of SaTScan statistics appeared the same as local spatial autocorrelation and almost showing the existence of 5 cluster areas.The geographical distribution of clusters where schistosomiasis was prevalent showed that it was closely corresponded to the middle and lower Yangtse river and in particular, many clusters were located near the boundary of Hubei and Hunan province.

Background Schistosoma japonicum is a major public health concern in the Peoples' Republic of China (PRC), with over one million people infected and another 50 million living in areas at risk of infection. Based on ecological, environmental, population genetic and molecular factors, schistosomiasis transmission in PRC can be categorised into four discrete ecosystems or transmission modes. It is predicted that the Three Gorges Dam (TGD) will impact upon the transmission of schistosomiasis in the PRC, with varying degree across the four transmission modes. We undertook longitudinal surveillance from 2002 to 2006 in sentinel villages both above and below the TGD across five provinces (Hunan, Jiangxi, Hubei, Anhui and Sichuan) to determine whether there was any impact of the TGD on schistosomiasis transmission during its construction. Here we present the results from a schistosomiasis-endemic village located above the dam in Sichuan Province. Results Baseline results showed a human S. japonicum prevalence of 42.0% (95% CI: 36.6-47.5). At follow-up, results showed that the incidence of S. japonicum infection in the selected human cohort in Shian decreased by three quarters from 46% in 2003 to 11.3% in 2006. A significant (P < 0.01) downward trend was also evident in the yearly adjusted (for water contact) odds ratios. Over the four years of follow-up, the incidence of S. japonicum infection in bovines declined from 11.8% in the first year to zero in the final year of follow-up. Conclusions The substantial decrease in human (75%) and bovine (100%) incidence observed in Shian village can probably be attributed to the annual human and bovine PZQ treatment of positives; as seen in drug (PZQ) intervention studies in other parts of PRC. If an increase in schistosome transmission had occurred as a result of the TGD, it would be of negligible size compared to the treatment induced decline seen here. It appears therefore that the construction of the TGD had virtually no impact on schistosomiasis transmission in Shian village over the period of study. Furthermore, contrary to previous reports from Sichuan downplaying the role of animals in human schistosome transmission, bovines may indeed play a role.

Significant progress has taken place over the past 50 years in the control of schistosomiasis japonica in China. However, the available data suggested that schistosomiasis has re-emerged shortly after the World Bank Loan Project which was conducted from 1992 to 2001. The national control program with a revised strategy to control schistosomiasis by using integrated measures has been implemented since 2005. In this study, we aimed to evaluate the effect of the national program on schistosomiasis control from 2005 to 2008.A retrospective study was carried out to analyze the epidemic patterns of acute infections with Schistosoma japonicum (S. japonicum), based on the number of acute cases annually collected from the web-based national communicable diseases reporting system from 2005 to 2008.A total of 564, 207, 83 and 57 acute cases infected with S. japonicum were reported nationwide in 2005, 2006, 2007 and 2008, respectively, with an average annual reduction rate of 46.35% during last four years. Six outbreaks of acute infection with S. japonicum were reported in 2005 but none in the period of 2006 to 2008. All acute cases that were reported mainly came from the lake regions and became infected during the higher risk periods from the 27th to 43rd weeks of the year. Most of these cases are students (44.87%), farmers (31.51%) and fishermen (7.79%) who got the infection by water contact mainly through swimming (41.49%) and production activities (40.25%). With time, the proportion of imported cases among all acute cases increased due to more frequent movement of people that has occurred with a more mobile population.The national control program on schistosomiasis aliened with the revised control strategy has been effectively brought into effect. However, there is still a significant risk of infection among students, farmers and fishermen living in the lake regions. Therefore, it is important to strengthen control measures among risk populations in the high risk areas of transmission, or the lake regions.

To evaluate the practical value and the advantages of globe geographical positioning with wireless communication monitoring and supervision system in the field survey.Spots which were randomly sampled by the National Ministry of Health for the investigation were chosen in the endemic areas for schistosomiasis in Jiangsu, Jiangxi, Anhui, Hunan, Hubei, Sichuan and Yunnan provinces. Portable GPS CEC9680 was used for collecting relevant waypoints and track, recording on-the-spot geographical positions. The positioning data package was sent back synchronously in the form of short message of SMS to the monitoring service center, and the moving routes of the terminal receiver monitored were displayed on the GIS map to achieve real-time supervision and staff scheduling.With globe geographical positioning with wireless communication monitoring and supervision system, accurate positioning of 12 spots in the provinces of Jiangsu and 3 trial spots for schistosomiasis control with comprehensive treatment designated by the State Council has been established with real-time communicating recording, and monitoring systems.The globe geographical positioning with wireless communication monitoring and supervision system has provided a technical platform for the survey of schistosomiasis and other infectious diseases.

To use the snail survey data of Yugan, Jiangxi Province as an example to evaluate the effects and advantages of global positioning system integrated with digital maps and remote sensing data in order to manage and analyze the whole country's surveillance data of schistosomiasis by using geographic information system.The data of geographic information and snail information of 20 marshlands in Yugan, Jiangxi Province were collected, and by the correction of remote sensing images based on the digital maps and index extraction, the snail current situation and trend were analyzed and expressed.A series of specific procedure images of these 20 marshlands was established and the effects of Yugan surveillance platform based on geographic information system were validated.The whole country's surveillance data of schistosomiasis might be successfully integrated with geographic information system by global positioning system and be managed and expressed, which supplies a successful platform in using the surveillance data effectively.

Possible impact of ecological and social environmental changes due to the construction of the Three Gorges Dam on the transmission of schistosomiasis draws great attention of the health authority and publics. This article reviews the situation and progress of research on schistosomiasis transmission in reservoir area from three aspects: the possibility of snail spreading and breeding, imported infection sources and social behavioral factors of the people.

600 million Chinese have parasitic infections. One of the most important, from the public health and clinical perspectives, is undoubtedly schistosomiasis