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Schistosomiasis japonica is a zoonosis with a number of mammalian species acting as reservoir hosts, including water buffaloes which can contribute up to 75% to human transmission in the People's Republic of China. Determining prevalence and intensity of Schistosoma japonicum in mammalian hosts is important for calculating transmission rates and determining environmental contamination. A new procedure, the formalin–ethyl acetate sedimentation-digestion (FEA–SD) technique, for increased visualization of S. japonicum eggs in bovine feces, is described that is an effective technique for identifying and quantifying S. japonicum eggs in fecal samples from naturally infected Chinese water buffaloes and from carabao (water buffalo) in the Philippines. The procedure involves filtration, sedimentation, potassium hydroxide digestion and centrifugation steps prior to microscopy. Bulk debris, including the dense cellulosic material present in bovine feces, often obscures schistosome eggs with the result that prevalence and infection intensity based on direct visualization cannot be made accurately. This technique removes nearly 70% of debris from the fecal samples and renders the remaining debris translucent. It allows improved microscopic visualization of S. japonicum eggs and provides an accurate quantitative method for the estimation of infection in bovines and other ruminant reservoir hosts. We show that the FEA-SD technique could be of considerable value if applied as a surveillance tool for animal reservoirs of S. japonicum, particularly in areas with low to high infection intensity, or where, following control efforts, there is suspected elimination of schistosomiasis japonica. Author Summary: Schistosomiasis japonica, a chronic human parasitic disease in the People's Republic of China, the Philippines and areas of Indonesia, is a zoonosis with over 40 different mammals, including a number of ruminants, that can act as reservoir hosts for the infection. Precise identification of the major infection reservoirs is important for the control of Schistosoma japonicum as their targeted treatment can prevent environmental contamination and transmission of the parasite, thus reducing the risk to humans. Current copro-parasitological techniques are generally unsatisfactory for identifying and quantifying S. japonicum eggs in ruminant feces due to the large volume of cellulosic debris present. The new approach we describe here, the FEA–SD technique, removes much of this material by sieving and centrifugation with ethyl actate and renders any remaining debris transparent by use of a potassium hydroxide (KOH) digestion, providing much improved visualization of eggs, enabling the collection of more accurate data on S. japonicum infection in ruminants. This new tool will be of particular value for monitoring schistosome prevalence and intensity in animal reservoirs in areas of the People's Republic of China that are heading toward schistosomiasis elimination. [ABSTRACT FROM AUTHOR]

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<0.001). Seropositivity of IHA_JX in children aged 6-9 years old showed an excellent correlation with prevalence of schistosome infection in the seven communities (r = 0.77, P<0.05). Conclusions/Significance: Studies suggest that ELISA_SZ could be used to guide selective chemotherapy in moderate or low endemic regions. IHA_JX could be used to as a surveillance tool and for certifying elimination of schistosomiasis through monitoring children as a sentinel population. [ABSTRACT FROM AUTHOR]

Background to the debate: Triggered by a fascinating publication in the New England Journal of Medicine detailing China's new multi-pronged strategy to control and eventually interrupt the transmission of Schistosoma japonicum, this PLoS Neglected Tropical Diseases Debate critically examines the generalizability and financial costs of the studies presented from the marshlands of the lake region. Edmund Seto from the University of California and colleagues emphasize that the epidemiology and control of schistosomiasis varies according to the social-ecological context. They conjecture that the successful intervention packages piloted in the lake region is not fully fit for the hilly and mountainous environments in Sichuan and Yunnan provinces, and hence call for more flexible, setting-specific, and less expensive control strategies. In response, Xiao-Nong Zhou from the National Institute of Parasitic Diseases at the Chinese Center of Disease Control and Prevention and colleagues explain the steps from designing pilot studies to the articulation and implementation of a new national control strategy through a careful process of scaling-up and adaptations. Finally, the two opponents converge. The need for integrated, intersectoral, and setting-specific control measures is stressed, supported by rigorous surveillance and continuous research. Experiences and lessons from China are important for shaping the schistosomiasis elimination agenda. [ABSTRACT FROM AUTHOR]

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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<0.001 for both comparisons). The rate of infection in humans in control villages fluctuated but remained at baseline levels. In intervention villages, the percentage of sampling sites with infected snails decreased from 2.2% to 0.1% in one grassland area and from 0.3% to no infection in the other (P<0.001 for both comparisons). The rate of infection in mice after exposure to lake water decreased from 79% to no infection (P<0.001). Conclusions: A comprehensive control strategy based on interventions to reduce the rate of transmission of S. japonicum infection from cattle and humans to snails was highly effective. These interventions have been adopted as the national strategy to control schistosomiasis in China. N Engl J Med 2009;360:121-8. [ABSTRACT FROM AUTHOR]

Increasing evidence indicates that dams impact riverine ecosystems and human diseases. Poyang Lake, one of the largest schistosomiasis endemic environments in China, will change due to the construction of the Yangtze River Three Gorges Dam. We assess changes in Oncomelania hupensis hupensis, the snail host for Schistosoma japonicum, in response to changing water levels and weather from 1998 to 2002. In the 5 years following the major flooding of Poyang Lake in 1998, seasonal water levels have gradually decreased, concomitant with decreases in mean and variance of fall snail densities. Nonlinear relationships suggest that the highest spring density is associated with current, 2-, and 3-month prior temperatures of 18°, 9.1°, and 5.8°C, while the highest fall density is associated with 2- and 3-month prior water levels of 17 and 18 m, respectively. This suggests that lower, more stable water levels downstream of the dam may result in a reduction in mean fall densities and their variance. However, additional data are needed to determine whether snail populations that are typically destroyed by seasonal floods may live longer in more stable environments created by the dam. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Abstract: To further strengthen the evidence-base of artemether for the control of schistosomiasis japonica, a randomised controlled trial was carried out in the Poyang Lake region, a highly endemic area in southern China. A total of 783 individuals, aged 6–60 years, were enrolled. They were first given a single oral dose of praziquantel (50mg/kg). Then, they were randomly assigned oral artemether (6mg/kg) or placebo, administered once every 2 weeks for 9–11 doses, covering the entire transmission season for Schistosoma japonicum in 2004. Stool examination 1 month after the final dosing revealed eggs of S. japonicum in 3/373 (0.8%) of the artemether recipients and 56/361 (15.0%) in placebo recipients (χ 2 =53.69, P <0.001). Compared to the baseline, the geometric mean intensity of S. japonicum infection had decreased by 96.1% in the artemether group, and increased by 50.8% in the placebo group. No acute cases of schistosomiasis japonica were observed in the artemether group, whereas three such cases were reported from the placebo group. Compliance with regard to multi-doses of artemether and placebo was 84.9, and 77.9%, respectively. This study confirms that repeated oral artemether produces no drug-related adverse effects, significantly reduces incidence and intensity of patent S. japonicum infection and results in high compliance. Hence it can be used as an additional tool for the control of schistosomiasis japonica in the lake regions of China. [Copyright &y& Elsevier]

Abstract Soil transmitted helminths (STHs) burden was enormous in China several decades ago, however, rigorous control efforts have been successful with appreciable reduction in diseases burden. Here, we assessed provincial-level data derived from cross sectional surveys, executed in 1989, 2002 and 2014, on the prevalence of STHs among populations in Jiangxi province, China. This study, also, reported STHs integrated control intervention aimed at reducing STHs transmission and worm burden among population at county-level. The intervention strategies included mass drug administration (MDA), health education, improved water supply for drinking, improved sanitary facilities and environmental modification in Guixi municipality. The overall infection rate of STHs in Jiangxi province decreased from 77.7% (1989) to 6.3% (2014), while Ascaris lumbricoides , hookworm and Trichuris trichiura decreased from 71.1%, 17.6% and 17.0% (1989) to 0.9%, 4.7% and 1.0% (2014), respectively. STHs infection rates in female population were higher than male in the three surveys. Reduction in STHs prevalence was observed in all age groups, but the decline was less in higher age group. STHs prevalence in Guixi intervention region indicated remarkable reduction from 31.8% (2006) to 6.1% (2009) (χ 2＝255.22, P ＜0.01). A. lumbricoides , hookworm and T. trichiura infection rates decreased from 10.4%, 17.0% and 7.1% (2006) to 0.1%, 4.1% and 2.2%, respectively (2009) (X2 A.l = 110.23, P<0.01; X2 hk = 103.57, P < 0.01; X2 T.t = 32.0, P < 0.01). A. lumbricoides infection rate declined the most of all STHs. Following control efforts with integrated control intervention strategies, STHs prevalence in Jiangxi province experienced remarkable trend in decline between 1989 and 2014. Consolidating control efforts with sustained integrated control strategies is, therefore, important to achieving STHs elimination in China. [ABSTRACT FROM AUTHOR]

Abstract: Human helminthiases are common in China, especially in rural areas where sanitation conditions are poor. Co- and multiple infections with helminths are strikingly frequent. A cross-sectional parasitological and questionnaire survey was carried out in a population of 3205 individuals belonging to 498 families from five villages in the Poyang Lake region, Jiangxi Province, China, to assess their helminth infection status and to collect information on risk factors for infection. The prevalences for Ascaris lumbricoides, Schistosoma japonicum and Trichuris trichiura were 30.9%, 15.7% and 47%, respectively. Hookworm infection prevalence was low (0.7%). A significant association was observed between A. lumbricoides and T. trichiura infection, and also between S. japonicum and T. trichiura infection. Variance components analysis was undertaken to investigate the aggregation of S. japonicum and the soil-transmitted helminths, A. lumbricoides and T. trichiura. While A. lumbricoides was found to aggregate only at a household level, T. trichiura was shown to cluster predominantly in families. Both genetic and household effects were found to be important in determining the risk of infection with S. japonicum. Variance components analysis for A. lumbricoides/T. trichiura co-infections indicated a significant domestic environmental effect, attributable for 32.7% of the co-infection risk. Aggregation of S. japonicum/T. trichiura co-infection was also observed at a household level. The risk of infection with multiple helminth species, although mainly environmentally influenced, was also shown to have significant involvement of genetic and household components. The results of this study indicate that a shared household is a major contributing risk factor for helminth co-infections and emphasises the need for increased standards of sanitation and hygiene to prevent parasite transmission. Further, the results suggest that susceptibility to one helminth infection is not completely independent of another, and that there exist common genetic factors underlying infection with multiple helminth species. [Copyright &y& Elsevier]

Objective: To understand the epidemiological features and changing patterns of intestinal parasitic diseases in Jiangxi Province from 1989 to 2014, so as to provide scientific evidence for formulating the preventive and control strategy for intestinal parasitic diseases., Methods: The data regarding the status of intestinal parasitic diseases in Jiangxi Province were captured from the 1989 national survey on the distribution of human parasites in China and the 2014 national survey on major human parasitic diseases in China, and the status of human intestinal parasite infections was compared between the two surveys in Jiangxi Province., Results: The prevalence rate of human intestinal parasite infections was 79.59% and 9.64% in Jiangxi Province in 1989 and 2014, with a decline rate of 87.89% during the 25-year period ( χ 2 = 30 870.5, P < 0.01). There were 24 and 20 species of human intestinal parasites detected in Jiangxi Province in 1989 and 2014, respectively, with totally 26 species detected during the two surveys. In Jiangxi Province, the 3 most highly prevalent human intestinal parasites included Ascaris lumbricoides (71.06%), hookworm (17.61%) and Enterobius vermicularis (17.59%) in 1989, and E. vermicularis (13.73%), hookworm (4.66%), whipworm (0.95%) in 2014. A higher rate of human intestinal parasite infections was found in females than in males in both surveys in Jiangxi Province ( P < 0.01), and the prevalence of human intestinal parasite infections reduced by 82.50% to 95.31% in different age groups in Jiangsu Province during the 25-year period., Conclusions: The prevalence of human intestinal parasite infections shows a remarkable decline tendency in Jiangxi Province, and soil-transmitted nematodes remain the main species of human intestinal parasites in Jiangxi Province.

Objective: To evaluate the effects of a novel molluscicide, the salt quinoid-2', 5-dichloro-4'-nitrosalicylanilide from niclosamide (LDS), with 10% wettable powder, in main schistosomiasis epidemic areas of China, including Hunan, Jiangxi, Hubei, Anhui, Jiangsu, Sichuan, Yunnan and Zhejiang Province., Methods: In the immersion test, 6 effective concentrations of 10% LDS were tested respectively: 0.1, 0.2, 0.4, 0.6, 0.8, 1.0 g/m3 in the field; at the same time, 50% wettable powder of niclosamide ethanolamine salt (WPN) with effective concentrations of 1.0 g/m was used as the molluscicide control, and the fresh water as the blank control, then the mortality rates of 0. hupensis snails were recorded at 24 h, 48 h and 72 h after the immersion. In the spraying test and powder-spraying test, 5 effective dosages of 10% LDS were tested respectively: 0.2, 0.4, 0.6, 0.8, 1.0 g/m2, while 50% WPN 1.0 g/m2 was used as the molluscicide control, and the fresh water as the blank control in the field for 1 d, 3 d and 7 d, then the mortality rates of O. hupensis snails were recorded at 1 d, 3 d and 7 d after the spraying and powder-spraying., Results: The snail mortality rates of LDS using the immersion test for 72 h were more than 95% in the field of eight provinces (0.1 g/m in Sichuan, Jiangxi, Jiangsu and Zhejiang provinces, 0.2 g/m3 in Yunnan, Hunan and Hubei provinces, and 0.4 g/min Anhui Province); the snail mortality rates of LDS using the spraying test for 7 d were more than 85% (0.2 g/m2 in Hunan, Hubei, Jiangxi and Zhejiang provinces, 0.4 g/m2 in Sichuan and Anhui provinces, 0.6 g/m2 in Yunnan and Jiangsu provinces). The snail mortality rates of LDS the powder-spraying test for 7 d were more than 85% (0.6 g/m2 in Yunnan, Sichuan, Hubei, Jiangxi, Anhui, Jiangsu and Zhejiang provinces). According to the standards of "Efficacy test methods and evaluation of molluscicide for pesticide registration (NY/T 1617-2008)", LDS is a qualified molluscicide., Conclusions: LDS has good molluscicidal effects through the immersion, spraying and powder-spraying test in the fields. It is suitable for a variety of environments to control O. hupensis snails of schistosomiasis endemic areas in China. The recommended dosages of LDS are 0.1-0.2 g/m3 by the immersion method, 0.2-0.4 g/m2 by the spraying method, and 0.4-0.6 g/m2 by the powder-spraying method in the fields.

Objective: To understand the characteristics of schistosome cercarial infested water contact of residents in Poyang Lake endemic areas after the operation of Three Gorges Project, so as to provide the evidence for formulating a well-directed control strategy., Methods: The residents in two villages in schistosomiasis endemic areas were selected and surveyed for their activities of infested water contacts by questionnaire., Results: The proportion and frequency of infested water contacts of residents in Poyang Lake region were high and the average rate of infested water contacts was 69.77%, and 98.96% of infested water contacts occurred in spring, summer and autumn. The main ways of infested water contacts were fishing/swimming/playing for adult men, washing clothes/fishing for adult women, and swimming/playing for school children, respectively. The rates of infested water contacts were 73.33%, 71.63% and 61.87% in adult men, women and school children, respectively. The frequencies of infested water contacts > 1 time/week, 1 time/week-1 time/month, and < 1 time/month were 62.61%, 23.74% and 13.66% respectively., Conclusions: The infested water contacts mainly occurs in spring, summer and autumn, and the main way of infested water contacts was fishing. Farming and mowing grass, which had been the primary way, now become the secondary way for the adult residents.

Background: In recent field surveys, we failed to detect the presence of specific antibody against Schistosoma japonicum in some egg-positive patients by commonly used immunodiagnostic kits. To find out whether low levels of specific antibody truly exist among egg-positive individuals and elucidate the underlying immune mechanisms, we carried out a cross-sectional epidemiologic study in a S. japonicum low transmission endemic area of Poyang Lake region, China and compared the humoral and cellular immune characteristics between S. japonicum high and low antibody responders., Methods: Kato-Katz thick smear assay was used to determine the schistosomiasis status of 3,384 participants residing in two Poyang Lake region villages, Jiangxi, China. Among the 142 stool egg-positive participants, we identified low and high S. japonicum antibody responders with soluble egg antigen (SEA) and adult worm antigen (AWA) specific IgG levels by adopting ROC curve analysis. To compare the humoral and cellular immune responses between high and low S. japonicum antibody responders, serum specific antibody levels as well as the percentage of T lymphocyte subpopulation in PMBC, and cell stimulated cytokines (IFN- gamma and interlukin-10) were detected., Results: Eight S. japonicum egg-positive participants were defined as low antibody responders. Although the percentage of CD3⁺T cells in low responders was slightly higher and the percentage of CD4⁺ T cells, CD8⁺ T cells, the ratio of CD4⁺/CD8⁺ and CD4⁺ CD25⁺ Treg cells were lower than those in high responders, the differences between the two groups were not significant (P > 0.05). AWA -stimulated interlukin-10 level was significantly higher in high responders, while other cytokines did not show differences between two groups. For antibody profiles, except AWA specific IgA, significant differences of each antibody isotype between low and high responders were detected (P < 0.05)., Conclusions: Our study confirmed that there are S. japonicum antibody low responders among schistosome egg-positive residents in S. japonicum low-transmission areas in China. Thus, mis-diagnosis using immune-diagnosis kits do exist. Significant differences of responding antibody levels between low and high responders were detected, while no major cellular response changes were observed.

Objective: To analyze the status of prevalence and control of schistosomiasis in Jiangxi Province from 2002 to 2012., Methods: Endemic status and control effectiveness during the period from 2002 to 2012 was analyzed by using a combination of field survey, data collection and retrospective investigation., Results: From 2002 to 2012, schistosomiasis control made significant achievements in Jiangxi Province. The number of counties which have reached the criteria of transmission interruption of schistosomiasis increased from 19 in 2002 to 22 in 2012. The number of patients with schistosome infection decreased from 128 331 in 2002 to 73 102 in 2012. The positive rate of serological test and fecal examination in residents decreased from 12.2% and 4.2% in 2002 to 5.2% and 0.4% in 2012, respectively. Acute infection reduced from 146 cases in 2002 to 3 cases in 2012, but advanced cases increased by 42.4%. The positive rate of fecal examination in cattle reduced from 4.7% in 2002 to 1.3% in 2012. The density of living snails and infected snails significantly decreased to 0.083 5/0.1 a? and 0.000 037/0.1 m2 in 2012, respectively. However, the snail-ridden areas slightly increased. Jiangxi Province reached the criteria of endemic control for schistosomiasis in 2008. During 2002-2012, control activities were intensified. Examination and chemotherapy for human increased by 65.2% and 65.5%, while 23.4% and 251.1% for cattle. Mean while, area with snail control activities increased by 617.8%. An integrated strategy of infection source control was implemented in the Province., Conclusion: During 2002 to 2012, endemic index of schistosomiasis in Jiangxi showed a steady decline after 2005. Currently, schistosomiasis prevalence shows a low level. The endemic indicators of infection in human and livestock as well as Oncomelania snails have been kept stable at low level.

Objective: To clarify new features of hydrological regime in the Poyang Lake after runs of the Three Gorges Project and its impact on the prevalence of schistosomiasis in this region., Methods: It is collected information of Three Gorges Project, average daily water level from 2002 to 2012 at Duchang hydrological station in Poyang Lake and the data of prevalence and control of schistosomiasis in 12 endemic counties along the lake. It was analyzed the trends of prevalence of schistosomiasis under the changed condition of hydrologic situation., Results: Effects of impoundment of Three Gorges reservoir running on water level of Poyang Lake are mainly shown in: Water levels of the lake are suppressed throughout the year which was characterized by high water level in flood season dropped, lower water level appeared in the spring, water withdrew earlier and quicker in the fall and to an even lower level in dry season. After impoundment of Three Gorges Project, infection rate of Schistosomajaponica in human and in bovine decreased by 92.65% and 76.37% respectively in endemic areas around the lake. The density of Oncomelania snails decreased by 94.21%. Prevalent of schistosomiasis in this region showed a significant downward trend., Conclusions: After runs of the Three Gorges Project, regularized changes hydrologic conditions has taken place in Poyang Lake which is characterized by lower water level and thus might lead to lower density of Oncomelania snails on marshlands and reducing of prevalence of schistosomiasis. Significant strengthening of schistosomiasis control efforts might also contributed to the stable and low level of prevalence of schistosomiasis in the region.

Objective: To investigate the changing rules of schistosomiasis endemic situation before and after reaching the criteria of schistosomiasis transmission controlled or interrupted in hilly endemic areas of Jiangxi Province, so as to provide the evidence for reformulating the criteria of schistosomiasis control and eradication in the future., Methods: In the hilly areas of schistosomiasis endemic in Jiangxi Province, 2 counties where the transmission has been interrupted and 1 county where the transmission has been controlled were selected and investigated with the retrospective research method. The endemic detailed data were collected and recorded 10 years before reaching the criteria of transmission interrupted/controlled, and several years after reaching the criteria (ending in 2008), and then a database was established. The changing rules of endemic situation before and after reaching the criteria of transmission interrupted/controlled were analyzed and compared., Results: After reaching the criteria of transmission controlled, in the 3 counties, Guangfen, Shangrao and Dean, the declined rates of areas with Oncomelania hupensis snails were 96.79%, 98.99%, and 99.77% respectively. The snail density maintained a lower level, and 95% of infected persons and cattle were cured. The average time from transmission controlled to the transmission interrupted was 17 years in Guangfen County and 26 years in Dean County. However, in Shangrao County, the snail situation rebounded due to the snail re-found and spread although the schistosomiasis morbidity of population/animals maintained stably., Conclusions: After reaching the criteria of transmission interrupted/controlled, the remained snails were easy to re-find and spread under some certain condition, which is one of main obstacles for reaching the criteria of transmission interrupted. In an isolated snail unit, if the snail area and snail density are controlled in a very low level, it is still difficult to transmit and spread schistosomiasis even if there exist infectious sources.

Objective: To investigate the impact of the Water Conservancy Project of Poyang Lake after operation on Oncomelania hupensis snail habitats in 10 counties (cities or districts) around Poyang Lake., Methods: The data of the distribution, numbers, areas, elevation and slope, etc. of snail infested marshlands on upstream of the project site in Poyang Lake were investigated and collected. Accordingly, the status of the submerged and flooding areas of the marshlands were analyzed and calculated respectively in the case that the project ran by different water regulation schemes at 14, 13, 12 m and 11 m levels., Results: In accordance with the regulation and storage preset programs at 14, 13, 12 and 11 m water levels, the number and its areas of submerged marshlands, from downstream to upstream in Poyang Lake, in turn decreased. Under the condition of the regulation at the 14 m water level, the numbers of completely submerged and partially submerged marshlands as well as the submerged areas were accounted for 32.9%, 51.4% and 60.3% of the whole marshlands, respectively. At the 13 m water level regulation, they were 9.8%, 46.8% and 1.9% respectively. At the 11 m level, only part of 4 marshlands were flooded, which were accounted for only 0.5% of the total number of marshlands and 0.2% of whole areas of the marshlands., Conclusions: The Water Conservancy Project of Poyang Lake may create a condition for eliminating snails through water flooding. If implementing regulation at the 14 m level for two or three consecutive years, 60.3% of snail habits could realize the snail-free objective. However, if implementing the 11 m or 10 m water level regulation, there will be little impact on areas of snail habitats and the snail distribution in the Poyang Lake region from the point of view of "marshlands flooding". The impacts on marshlands in different counties might differ due to the location and elevation.

Objective: To evaluate the situation of realizing schistosomiasis transmission control in Jiangxi Province., Methods: The situation of reaching the criteria of schistosomiasis transmission control was evaluated by using the method of field surveys combined with retrospective investigations., Results: The schistosome infection in human was kept at a stable low level, and the infection rate in residents was below 1% in 90.24% (536/594) of whole epidemic controlled villages. There were 45 spots with schistosome infected Oncomelania hupensis snails in 38 pieces of marshland. The epidemic situation in livestock showed less optimistic than that in human, and the infection rate in bovine was higher than 1% in 19.87% (118/594) of the whole epidemic controlled villages., Conclusions: Currently, the prevalence of schistosomiasis is at a low level in 9 infection-controlled counties of Jiangxi Province. More favorable situation has emerged to the realization of schistosomiasis transmission control. However, it is necessary to strengthen the infectious sources control with emphasis on bovine so as to achieve the goal of transmission control in whole province in 2015.

Objective: To observe the characterization of cellular immune of schistosomiasis japonica patients in low endemic area of Poyang Lake region., Methods: The schistosomiasis patients who were positive by stool detections were selected as study subjects, and the individuals who were negative by stool detections in three consecutive years were selected as negative controls. The CD4+T cell, CD8+T cell and CD4+CD25+Treg in venous blood of the study subjects were detected by using flow cytometry. In vitro, cytokine (IFN-gamma and IL-10) production of PBMC in response to soluble egg antigen (SEA) and soluble worm antigen preparation (SWA) were measured by ELISA., Results: The levels of CD4+CD25+Treg in individuals who were positive by stool detections (5.99 +/- 1.60)% were higher than those of the negative (5.04 +/- 1.64)%, and the difference was significant (t = 3.261, P < 0.01). One year after the treatment, the levels of IFN-gamma were significantly higher (Stimulated by SEA before and after the treatment, the mean levels were 121.97 and 2 564.03 pg/ml, respectively; stimulated by SWA before and after treatment, the mean levels were 102.89 and 646.26 pg/ml, respectively) and IL-10 were significant lower in patients who were positive by stool detections (Stimulated by SEA before and after treatment, the mean level were 294.75 and 122.43 pg/ml, respectively; stimulated by SWAP before and after treatment, the mean cytokine levels were 110.10 and 31.85 pg/ml, respectively)., Conclusion: The increase of induced CD4+CD25+Treg is one of causes that down-regulate cellular immune of human body after infection with Schistosoma japonicum.

Objective: To understand the characterization and levels of antibody isotype responses to soluble egg antigen (SEA) and adult worm antigen (AWA) of Schistosoma japonicum in schistosomiasis patients in Poyang Lake region., Methods: Antibody isotype IgG, IgG1, IgG2, IgG3, IgG4, IgE, IgM and IgA responses to SEA and AWA in the sera of individuals from endemic and non-endemic areas were determined by indirect ELISA., Results: The levels of antigen-specific antibody isotypes in the sera of patients with egg positive were significantly higher than those of people with egg negative and normal control population from non-endemic area (P < 0.001), and except for anti-SEA IgG2 and anti-AWA IgG4 and IgE antibodies, the levels of antibody isotypes in the sera of people with egg negative in endemic area were significantly higher than those of normal control population from non-endemic area (P < 0.05). In the population with egg positive, children had higher levels of anti-SEA IgM and IgG1 and anti-AWA IgM antibody, and lower AWA specific IgG than adults. There was no significant difference between the male and female except for the male had higher levels of IgG (F = 4.677, P = 0.032) and IgG1 (F = 5.55, P = 0.020)against AWA. Three months post-treatment, the levels of IgG1, IgG3, IgG4 antibody responses to SEA deceased significantly (P < 0.001, P = 0.029, P = 0.044), and almost all the antibody levels decreased significantly (P < 0.05) twelve months post-treatment, except for SEA specific IgE and IgM and AWA specific IgG4 and IgM antibodies., Conclusions: The levels of antigen-specific antibody isotypes in the sera of patients with egg positive are significantly higher than those of people with egg negative and normal control population from non-endemic area. Almost all of antibody levels decrease significantly twelve months post-treatment. The levels of antibody isotypes in the sera of people with egg negative in endemic area are significantly higher than those of population from non-endemic area, giving a clue that the selection of negative control of schistosomiasis diagnostic kit should be noticed.

Objective: To evaluate the medium-term effect and stability of the schistosomiasis comprehensive control strategy based on infectious source control after its popularization and application in marshland endemic areas., Methods: The schistosomiasis comprehensive control strategy based on infectious source control including "replacing buffalo with machine", "marshlands isolation and grazing forbidden", etc. was implemented in all villages of Sanli Township, a heavy endemic area with schistosomiasis in Jianxian County. The infection situation of schistosomiasis in population and Oncomelania snails in 4 villages around the lake were monitored regularly for 6 consecutive years., Results: The infection rate of schistosomiasis in population significantly decreased after the comprehensive control measures were carried out. Two years later, the infection rate in Huangjia Village was 0, and was sustained at zero for 5 consecutive years; the infection rate in Fengfu Village decreased by 77.24% and stabilized to zero for the next three years; the population infection rates in Fanrong Village and Caomen Village decreased by 82.33% and 82.53%, respectively, then the infection rates of the two villages kept under 1% and were 0 for 2 years and 1 year, respectively. The number of spots with infected snails in two marshlands in pilot areas decreased yearly from 10 before the intervention to 0, in which, the infection rate of snails and the number of spots with infected snails in Huangjiaoniu Marshland and Goulian Marshland decreased to zero 1 year and 3 years after the strategy was implemented, respectively, and the infected snails were not found in these marshlands in following years., Conclusion: Strengthening the management of buffaloes in surrounding areas and utilizing marshland resources is the main measure that can consolidate and expand the medium-term and long-term effect of the schistosomiasis 2.2 comprehensive strategy based on infectious source control.

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&#95;JX), an enzyme linked immunosorbent assay (ELISA&#95;SZ), and a dot immunogold filtration assay (DIGFA&#95;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&#95;SZ performed significantly higher sensitivity (95.45%, 95%CI: 92.94-97.97%) than IHA&#95;JX (87.59%, 95%CI: 83.51-91.49%) and DIGFA&#95;SH (79.55%, 95%CI: 74.68-84.41%), especially in subgroups with very low infection intensity. The specificity of ELISA&#95;SZ, IHA&#95;JX, DIGFA&#95;SH in 6-9 year olds with occasional exposure was nearly 90%. DIGFA&#95;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&#95;JX with results of stool examination in age strata (r = 0.70, P<0.001). Seropositivity of IHA&#95;JX in children aged 6-9 years old showed an excellent correlation with prevalence of schistosome infection in the seven communities (r = 0.77, P<0.05)., Conclusions/significance: Studies suggest that ELISA&#95;SZ could be used to guide selective chemotherapy in moderate or low endemic regions. IHA&#95;JX could be used to as a surveillance tool and for certifying elimination of schistosomiasis through monitoring children as a sentinel population.

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.

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.

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.

Objective: To evaluate the effectiveness of routinely used assays for schistosomiasis diagnosis in the field., Methods: From late November to early December 2005, 6-65 years old inhabitants from 3 endemic villages were examined by Kato-Katz technique (3 thick smears) and nylon bag sedimentation/hatching method. At the same time, dipstick dye immunoassay(DDIA), fast enzyme linked immunosorbent assay (F-ELISA), indirect haemagglutination test A (IHA-A) and B ( IHA-B) were carried out in parallel, Results: 1864 people were examined by stool examination with an average positive rate of 9.7%. The missing rate of DDIA was relatively stable in medium and heavily endemic areas of schistosomiasis. The missing rate of nylon bag sedimentation/hatching method was 25% and relatively stable when the number of eggs per gram of feces(EPG) was larger than 100. The average positive rate of DDIA, F-ELISA, IHA-A and IHA-B was 47.8%, 50.0%, 66.3% and 40.1% respectively. Using stool examination as the gold standard, the sensitivity of DDIA, F-ELISA, IHA-A and IHA-B was 75.3%, 65.8%, 85.6% and 76.0%; and the specificity was 55.1%, 51.7%, 35.7% and 63.6%, respectively. Among the four sero-diagnostics, the specificity, Youden index, positive likelihood rate and coincidence of IHA-B were the highest., Conclusion: Kato-Katz method is more stable and effective than nylon bag sedimentation/hatching method in medium and heavily endemic areas of schistosomiasis japonica. The sensitivity and specificity of these four diagnosis kits are lower than 90%.

Objective: To develop a quantitative method for the determination of akebia saponin D in root of Dipacus asperoides and provide scientific basis for quality control of D. asperoides., Method: An IPLC analytical method was established using Kromasil ODS column with acetonitrile-water (30:70) as mobile phase and the detection wavelength was 212 nm., Result: The akebia saponin D in root extract were well separated by this method. The linear range is between 0.582 5-9.32 microg, r = 0.9999. The average recovery and RSD of repeatability are 100.3%, 2.3%, respectively., Conclusion: This method is simple, accurate and reliable by evaluating the method validation data and can be used for the quality control of D. asperoides and its preparations.

Background: The serotonin transporter (5-HTT) and tryptophan hydroxylase (TPH) gene are important candidate genes for the psychiatric disorders. Many studies of patients with anxiety disorders have found abnormalities of serotonin metabolism and dysfunction of regulation in the transporter itself. In this study, we hypothesize that genetic variation in the 5-HTT and TPH gene may have an effect on the etiology of generalized anxiety disorder (GAD)., Methods: Using a polymerase chain reaction-based technique, the allele and genotype frequencies of three polymorphisms in the serotonin transporter gene (a deletion/insertion polymorphism in the transcriptional control region and a variable number of tandem repeats in intron 2) and TPH gene (A218C in intron 7) were analyzed in 138 patients with GAD and 90 healthy controls. These two groups were matched for ethnic and geographic origin., Results: The frequencies of 5-HTT gene-linked functional polymorphic region (5-HTTLPR) SS (short/short) genotype were significantly higher in GAD patients than in control subjects (68% versus 49%, chi = 12.274, df = 2, P = 0.002), and the frequencies of S (short) allele observed in the GAD patients were higher than those in healthy subjects (79 versus 71%, chi = 4.063, df = 1, P = 0.044). The odds ratio for the SS genotype versus the other two genotypes was 2.33 (95% confidence interval, 1.29-3.86). Similarly, the odds ratio for the S allele versus L allele was 1.56 (95% confidence interval, 1.01-2.41). The genotypic and allelic distribution of 5-HTT VNTR and TPH A218C polymorphisms did not show statistically significant differences between patients and controls., Conclusion: Our findings support that the presence of 5-HTTLPR-SS genotype may increase the risk of GAD.

Objective: To analyze factors affecting transmission of schistosomiasis japonica in Poyang Lake., Methods: Successive surveillance data for at least three years from 1992 to 1998 at the schistosomiasis endemic administrative villages surrounding Poyang Lake were collected, including the egg positive rate by stool examination, investment on treatment of patients and mollusciciding in snail habitat, risk areas, bovine infection rate. Data on rainfall and temperature were also obtained from the relevant agencies. Step-wised regression method was employed to analyze the data., Results: The regression model established is statistically significant, R2 equals 0.735, P < 0.01. The accepted variables affecting the transmission of the disease were natural logarithm of human infection rate in last year, risk areas, infection rate of bovine, investment values of niclosamide per risk area and value of praziquantel administered per infection rate., Conclusion: Chemotherapy and mollusciciding effectively reduced schistosomiasis transmission in Poyang lake region, while the infection rate, risk areas, bovine infection rate still drive the transmission.

An epidemiologic survey among four administrative villages around Poyang Lake, in Jiangxi Province, China (two experimental and two controls) is being conducted to determine if bovine infections are responsible for the persistence of human schistosomiasis transmission on Yangtze River marshlands. A previously published paper presented the experimental design and baseline data for humans and bovines. This paper presents basic data for the four villages using remote sensing, and baseline data for snails that includes geographic information systems and remote sensing technology to classify the areas of bovine grazing ranges and habitats suitable for snails. A new method for sampling Oncomelania snails in China is used to determine the distribution, density, and infection rates of snails throughout the grazing ranges from season to season over a four-year period. Hypothetically, treating bovines should reduce infection rates in snails to below the critical number necessary to maintain infections in man and bovines.

Objective: To identify snail habitats and monitor the changes by combining remote sensing technique with the ground-based ecological data., Methods: Of 100 survey sites selected throughout Poyang Lake, 75 were randomly identified from 574 land mass units: 50 were from snail habitats and 25 were from non-snail habitats based on a historical survey (1982-1984); 25 sites with habitats that did not have snails were also selected. Each site, covering 10,000 m2, was divided into a grid of 100 cells from which 20 cells were randomly selected. Snails, when present, were collected from a 4 m2 frame placed in the center of the selected cell. Satellite Landsat TM images were obtained for the same period as the ground survey data collected. Unsupervised classification was used to classify the images. Identified land-cover types were correlated with snail habitat., Results: The sensitivity and specificity of classified snail habitat were 90.0%-95.6% and 61.1%-68.6%, respectively. Based on the classification, estimated snail habitat areas in Poyang Lake increased from 623.4 km2 in 1999 to 762.8 km2 in 2000., Conclusion: Snail habitats are associated with grassland-covered areas. Classified images can be used to identify snail habitats, determine their areas, and monitor snail habitat changes caused by annual fluctuations of key environmental factors.