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Background: Owing to the harmfulness and seriousness of Schistosomiasis japonica in China, the control and prevention of S. japonica transmission are imperative. As the unique intermediate host of this disease, Oncomelania hupensis plays an important role in the transmission. It has been reported that the snail population in Qiangliang Lake district, Dongting Lake Region has been naturally declining and is slowly becoming extinct. Considering the changes of environmental factors that may cause this phenomenon, we try to explore the relationship between circumstance elements and snails, and then search for the possible optimum scopes of environmental factors for snails., Methods: Moisture content of soil, pH, temperature of soil and elevation were collected by corresponding apparatus in the study sites. The LISA statistic and GWR model were used to analyze the association between factors and mean snail density, and the values in high-high clustered areas and low-low clustered areas were extracted to find out the possible optimum ranges of these elements for snails., Results: A total of 8,589 snail specimens were collected from 397 sampling sites in the study field. Besides the mean snail density, three environmental factors including water content, pH and temperature had high spatial autocorrelation. The spatial clustering suggested that the possible optimum scopes of moisture content, pH, temperature of the soil and elevation were 58.70 to 68.93%, 6.80 to 7.80, 22.73 to 24.23°C and 23.50 to 25.97 m, respectively. Moreover, the GWR model showed that the possible optimum ranges of these four factors were 36.58 to 61.08%, 6.541 to 6.89, 24.30 to 25.70°C and 23.50 to 29.44 m, respectively., Conclusion: The results indicated the association between snails and environmental factors was not linear but U-shaped. Considering the results of two analysis methods, the possible optimum scopes of moisture content, pH, temperature of the soil and elevation were 58.70% to 68.93%, 6.6 to 7.0, 22.73°C to 24.23°C, and 23.5 m to 26.0 m, respectively. The findings in this research will help in making an effective strategy to control snails and provide a method to analyze other factors.

The dynamics of the Poyang Lake in Jiangxi province, People's Republic of China has been monitored to demonstrate the association of various variables with the distribution of schistosomiasis transmission with particular reference to the annual variation of the habitats for the Oncomelania snail, the intermediate host of Schistosoma japonicum. This was studied with multiple space-borne sensors, including the ENVISAT radar altimeter (RA-2) and MODIS/Terra radiometry data products such as the 16-day enhanced vegetation index, the 8-day sun reflectance, and the derived modified normalized difference water index. The measurements of physical properties were in good accordance with previous reports based on in situ gauge data, spectroradiometry and other optical methods, which encouraged us to build a predictive model based on reported geospatial constraints to assess the limits of potential variation of the snail habitat areas. The simulated results correspond fairly well with surveys conducted by local authorities showing a correlation coefficient of 0.82 between highpotential habitat areas and local estimates in a 9-year (2002-2010) analysis. Taken together, these data indicate that spaceborne observations and in situ measurements can be integrated and used as a first step of a monitoring system for control and analysis of the potential of schistosomiasis dissemination. Since the true range and intensity of transmission in the study region remain elusive at present, a long-term survey around the lake is warranted to build a robust, parametric model.

Background: Schistosomiasis remains a serious public health problem in affected countries, and routine, highly sensitive and cost-effective diagnostic methods are lacking. We evaluated two immunodiagnostic techniques for the detection of Schistosoma japonicum infections: circulating antibody and circulating antigen assays., Methods: A total of 1864 individuals (between 6 and 72 years old) residing in five administrative villages in Hubei province were screened by serum examination with an indirect hemagglutination assay (IHA). The positive individuals (titer ≥20 in IHA) were reconfirmed by stool examination with the Kato-Katz method (three slides from a single stool specimen). Samples of good serum quality and a volume above 0.5 ml were selected for further testing with two immunodiagnostic antibody (DDIA and ELISA) and two antigen (ELISA) assays., Results: The average antibody positive rate in the five villages was 12.7%, while the average parasitological prevalence was 1.50%; 25 of the 28 egg-positive samples were also circulating antigen-positive. Significant differences were observed between the prevalence according to the Kato-Katz method and all three immunodiagnostic antibody assays (P-value <0.0001). Similar differences were observed between the Kato-Katz method and the two immunodiagnostic antigen assays (P-value <0.0001) and between the antigen and antibody assays (P-value <0.0001)., Conclusion: Both circulating antibody and circulating antigen assays had acceptable performance characteristics. Immunodiagnostic techniques to detect circulating antigens have potential to be deployed for schistosomiasis japonica screening in the endemic areas.

Background: Schistosomiasis remains a major public health problem in China. The major endemic foci are the lake and marshland regions of southern China, particularly the regions along the middle and lower reach of the Yangtze River in four provinces (Hubei, Hunan, Jiangxi, and Anhui). The purpose of our study is to assess the effect of a new integrated strategy emphasizing infection source control to curb schistosomiasis in marshland regions., Methods: In a longitudinal study, we implemented an integrated control strategy emphasizing infection source control in 16 villages from 2005 through 2012 in marshland regions of Hubei province. The interventions included removing cattle from snail-infested grasslands, providing farmers with mechanized farm equipment, improving sanitation by supplying tap water, building lavatories and latrines, praziquantel chemotherapy, controlling snails, and environmental modification., Results: Following the integrated control strategy designed to reduce the role of bovines and humans as sources of Schistosoma japonicum infection, the prevalence of human S. japonicum infection declined from 1.7% in 2005 to 0.4% in 2012 (P<0.001). Reductions were also observed in both sexes, across all age groups, and among high risk occupations. Moreover, the prevalence of bovine S. japonicum infection decreased from 11.7% in 2005 to 0.6% in 2012 (P<0.001). In addition, all the 16 villages achieved the national criteria of infection control in 2008., Conclusion: Our findings indicate that the integrated strategy was likely effective in controlling the transmission of S. japonicum in marshland regions in China.

Schistosomiasis japonica, caused by Schistosoma japonicum infection, remains a major public health concern in China, and the geographical distribution of this neglected tropical disease is limited to regions where Oncomelania hupensis, the intermediate host of the causative parasite, is detected. The purpose of this study was to monitor the transmission of S. japonicum in potential risk regions of China during the period from 2008 through 2012. To monitor the transmission, 10 fixed surveillance sites and 30 mobile sentinel sites were selected in 10 counties of four provinces, namely Anhui, Jiangsu, Chongqing and Hubei. There were 8, 9, 6, 2 and 3 cases infected with S. japonicum detected in the 30 mobile sentinel sites during the 5-year study period, while 27 subjects were positive for the antibody-based serum test in the 10 fixed sentinel sites; however, no infection was found. In addition, neither local nor imported livestock were found to be infected. No O. hupensis snails were detected in either the fixed surveillance or the mobile sentinel sites; however, the snail host was found to survive and reproduce at Chaohu Lake, inferring the potential of transmission of the disease. It is suggested that the continuous surveillance of schistosomiasis japonica should be carried out in both the endemic foci and potential risk regions of China, and an active, sensitive system to respond the potential risk of transmission seems justified.

Objective: To explore the potential key risk factors of schistosomiasis transmission in potential endemic areas so as to provide the evidence for setting up the prediction and surveillance systems of schistosomiasis outbreak epidemic., Methods: From 2008 to 2012, fixed and mobile surveillance sites in potential endemic areas of 2 counties in Hubei Province were selected. The immunological assays and stool examinations were carried out to investigate the schistosome infection situation of local people, mobile population and livestock. The distribution of Oncomelania hupensis snails was investigated in risk areas and suspicious areas, and spreading patterns of snails were observed in the rivers that directly connected with the Yangtze River., Results: A total of 6 052 local people aged 6-65 years were screened by IHA immunological tests, and the positive rate of antibody was 1.19% (72/6 052). Totally 72 antibody positives were examined by Kato-Katz technique and there were no positives. A total of 5 004 mobile persons were tested by IHA immunological tests and the positive rate was 1.36% (68/5 004). Totally 68 antibody positives were examined by Kato-Katz technique and there were no positives. Totally 287.07 hm2 potential endemic areas were investigated for Oncomelania snail detection, and no snails were found. The investigation on snail spreading patterns and the surveillance on suspicious circumstances were carried out, with no snails found., Conclusions: In the schistosomiasis potential endemic areas, some positives of IHA immunological tests are found. Therefore, monitoring is still needed to be strengthened.

Objective: To analyze the impact of water transfer project from the Yangtze River to the Huaihe River on schistosomiasis transmission, and to evaluate the risk of the disease input to the potential endemic area in Anhui Province, namely the Chaohu Lake region., Methods: From 2008 to 2012, 1 fixed and 3 mobile surveillance sites in the Chaohu Lake area were selected, and the schistosomiasis infection situation of 615 local residents in the fix surveillance site was investigated in autumn of 2008 and 2012, while the schistosomiasis infection situation of 1603 mobile population in the 3 mobile surveillance sites were investigated in autumn of 2008 to 2012. All people were screened by indirect hemagglutination assay (IHA), and the positive ones were then examined by sedimentation method. 303 local livestock and livestock from schistosomiasis endemic areas were examined by stool hatching method in autumn of 2008 to 2012. From 2008 to 2012, the distribution of Oncomelania snails was investigated in risk areas and suspicious areas, and the snail spreading pattern was conducted through salvaging floaters in rivers connected with the Yangtze River. In addition, the Oncomelania snails were raised in the cages on the beaches of the Chaohu Lake, a control area, from 2007 to 2010, and their survival and reproduction capacity was observed., Results: In 2008 and 2012, 301 and 314 local residents were detected by IHA, but there were no positive found. From 2008 to 2012, a total of 1603 mobile population were examined by IHA, and the positive rate of antibody was 3.1% (49/1603); 75 individuals were examined by sedimentation method, and the positive rate was 36.00% (27/75). A total of 303 livestock were examined by stool hatching method, but no one showed positive. A total of 1630 km(2) in risk areas and 3551 km(2) in suspicious areas were surveyed, but there were no Oncomelania snails found. A total of 457.6 kg floating debris were investigated, and 11 Oncomelania snails were found. From 2007 to 2010, the survival rate of Oncomelania snails in two trail areas in the Chaohu Lake and in the control area was 88% (86/98), 51% (45/89), 30% (25/71), 24% (20/84) and 92% (85/92), 54% (50/92), 23% (12/52), 17% (13/79) and 96% (85/89), 52% (44/85), 26% (18/69), 18% (14/76), respectively, there were no statistical significance between the trial areas and the control area (χ1(2) = 3.78, P > 0.01; χ2(2) = 0.27, P > 0.01; χ3(2) = 2.51, P > 0.01; χ4(2) = 1.50, P > 0.01), and filial generation snails were found in each observation area from 2008 to 2010, the number was 156-312., Conclusion: The imported infectious sources of schistosomiasis have been found in the Chaohu Lake region, the possibility of imported exogenous Oncomelania snails spreading into the Lake and surviving and reproducing there is high. The risk of schistosomiasis input to the potential endemic area in Anhui Province is predicted to be high.

The diagnosis of Schistosoma japonicum (Sj) infection in low prevalence areas of the People's Republic of China is challenging due to the sensitivity of the detection methods, leading to an underestimation of the disease burden. We compared the sensitivities of the miracidium hatching test (MHT) with the modified Kato-Katz method (KK) and the combination of the two methods (KK-MHT) to detect Sj infection in low prevalence areas of China. The stool samples of 3,853 residents from 8 villages with a light to moderate prevalence (0-23%) of Sj infection were examined by KK, MHT and KK-MHT. The findings were inconsistent. The KK-MHT conbination gave more positives than either the KK or MHT alone. Using the KK-MHT, we determined the missed rates with the KK (mR(K)) and MHT (mR(H)) to be 30.1% and 10.2%, respectively. At light prevalence sites (infection rate < 10%) the mR(K) was 60.6%, significantly higher than the mR(K) of 22.3% found at moderate prevalence sites (10-23%). However, the mR(H) at the light and moderate prevalence sites were 11.54% and 9.90%, respectively (p > 0.05). The combination KK-MHT had the best sensitivity in low Sj prevalence areas in China and the KK method alone was the least sensitive. Using KK alone as a screening method will result in an underestimation of Sj infection disease burden.

Schistosomiasis japonica has a long history in the Philippines. In 1975, 24 endemic provinces were identified in the northern, central, and southern islands of the Philippines. More than five million people were at risk, with approximately one million infected. In 2003, new foci of infection were found in two provinces in the north and central areas. For the past 30 years, human mass drug administration (MDA), utilizing the drug praziquantel, has been the mainstay of control in the country. Recent studies have shown that the schistosomiasis prevalence ranges from 1% to 50% within different endemic zones. Severe end-organ morbidity is still present in many endemic areas, particularly in remote villages with poor treatment coverage. Moreover, subtle morbidities such as growth retardation, malnutrition, anemia, and poor cognitive function in infected children persist. There is now strong evidence that large mammals (e.g. water buffaloes, cattle) contribute significantly to disease transmission, complicating control efforts. Given the zoonotic nature of schistosomiasis in the Philippines, it is evident that the incidence, prevalence, and morbidity of the disease will not be controlled by MDA alone. There is a need for innovative cost-effective strategies to control schistosomiasis in the long term., (Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.)

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 monitor water body infestation in schistosomiasis high-risk areas with sentinel mouse technique., Methods: A total of 72 surveillance sites from 47 counties were selected in Hunan, Hubei, Jiangxi, Anhui, Jiangsu, Yunnan, and Sichuan. The water infectivity of Schistosoma japonicum was determined in the surveillance sites by using sentinel mice during June-July and September, 2012., Results: Among the 3,283 sentinel mice which were placed in 72 sites, 3,062 (93.3%) were recovered and dissected. Infected sentinel mice were found in six sites accounting for 8.3% (6/72) of the total surveillance sites, with an occurrence rate of sites with infected mice of 8.3% in June-July and 2.8% in September. 33 infected mice were discovered with a total infection rate of 1.08% (33/3,062). 1,085 adult worms were collected, with a mean worm burden of 32.9 worms per mouse in infected sentinel mice. 4 positive sites were in Hunan and 2 were in Jiangxi. Local acute schistosomiasis or suspected local acute cases which detected elsewhere were reported in 2 positive sites. Some follow-up activities were conducted in the 6 positive sites., Conclusion: Compared with those in 2010, the schistosomiasis risk areas are shrinking in 2012. However, some regions are still the schistosomiasis high-risk areas.

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.

Schistosomiasis japonica remains a major public health problem and the Poyang Lake region in Jiangxi province is one of the worst affected endemic areas. Buffaloes play a major role in the transmission of Schistosoma japonicum to humans. The aim of the present study was to increase understanding of the epidemic characteristics of schistosomiasis japonica in water buffaloes in the Poyang Lake region, after achieving the national mid-term goal, and to provide a basis for further interventions. The baseline prevalence in two villages in the Poyang Lake region in May 2010 was compared with respect to usage, sex and age in the total study population. Seasonal dynamics from May 2010 to May 2011 were observed in a natural village in the studied area. The baseline prevalence of infection in both villages (Caohui and Gaozhou) was 4.94% in May 2010. The prevalence in buffalo younger than 12 months was 12.82% in Caohui and 15.11% in Gaozhou, which was significantly higher than that found in those aged 13-24 months and older than 24 months. Of the 28 infected buffaloes, 82.14% (23) were younger than 12 months. The flow of seasonal dynamics showed that S. japonicum infection buffaloes were found from May to July and from November to January of the following year. This survey suggested that it is necessary to conduct two mass treatments (especially for young animals) in late March or early April and November, with an additional treatment of positive animals in July or June., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Backgrounds: Human schistosomiasis is caused by schistosome, with annual loss of over 70 million disability adjusted life years in the world. China is endemic with Schistosoma japonicum and large-scale chemotherapy with praziquantel has become the mainstay of control in China since 1990s. However, the control effects of mass treatment in the field have been uneven. Moreover, mass treatment has come into a wide use in other countries with limited health resources. Therefore, a better understanding of the control effect of mass treatment is in an urgent need., Methods: We performed a systematic search of the literature to investigate the control efficiency of annual community-wide treatment (ACWT, treatment to an entire community without any preliminary screening) with a single dose of PZQ (40 mg kg(-1) bodyweight) against schistosome in humans in China. Three Chinese literature databases, including China National Knowledge Infrastructure, WanFang and Chinese Scientific Journal Databases, and the PubMed were searched. Pooled prevalence ratios (prevalence after to before treatment) were used to assess effect. Our protocol is available on PROSPERO (No. CRD42013003628)., Results: 22 articles were included. Meta-analyses on data from 18 studies on one round of ACWT, 17 studies on two consecutive rounds and 6 studies on three consecutive rounds were performed. The results showed control effects of ACWT plus other measures were statistically significant, with prevalence ratios being 0.38 (0.31, 0.46) for one round, 0.28 (0.22, 0.35) for two rounds and 0.22 (0.10, 0.46) for three rounds. When ACWT was performed alone or with health education only, the values for one and two rounds were 0.389 (0.307, 0.492) and 0.348 (0.300, 0.403), respectively., Conclusions: The control effect of ACWT alone or with other measures is significant and increases with the number of rounds. Such program is recommended in high endemic areas and the criteria yet merit further assessment.

About 46 mammal species have been suspected as reservoir hosts for Schistosoma japonicum and therefore the track of the target parasites, in relation to definitive host species, may be of great importance in terms of theoretical and practical implications. The circadian rhythm of cercariae emergence, a genetically controlled behavior for parasites to adapt to their definitive hosts, may seem to be a perfect biological marker for S. japonicum. In this study, a late (or nocturnal) cercarial emergence pattern was observed on the parasites from one hilly region in Anhui of China, where rodents serve as reservoirs, and on the first generation of the parasites. Moreover, by using the circular statistics, the homogeneity of parasites in such trait was also demonstrated. All these provide evidence for the genetically controlled biological trait, which seems essential in the investigation of macro- or micro-dynamics of parasite transmission of interest. This is particularly true in the case of S. japonicum when multiple parasite isolates or strains are more likely to exist., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Objective: To understand the epidemiological characteristics and current status of newly confirmed advanced schistosomiasis patients in Hunan Province in 2011., Methods: The cases previously diagnosed or suspected as advanced schistosomiasis in Hunan Province were the subjects of this investigation. Questionnairing (demographical information, disease history, etc.), clinical examination (ascites syndrome, abdominal palpation), laboratory examination, and abdominal ultrasonography were used to confirm the diagnosis. Treatment was given to the patients., Results: In 2011, there were 620 newly discovered advanced schistosomiasis patients in Hunan Province, mainly distributed in Yueyang (300 cases, 48.4%), Changde (193 cases, 31.1%) and Yiyang (123 cases, 19.8%). The male-to-female ratio was 1.4:1. The average age of the patients was 60.4 +/- 12.4. 69.7% (432/620) of the patients were illiterate or with primary school education. 90.3% (560/620) of them were farmers. 162 (26.1%) cases were labour incapacity and 442 cases (71.3%) were with a weak labor ability before receiving medical treatment. The average time from discovery of schistosome infection to diagnosis of advanced schistosomiasis was (24.9 +/- 14.3) years. Among the 620 patients, 418 cases were with ascites (67.4%), 201 cases with splenomegaly (32.4%), and 1 case with multiple granuloma in the colon (0.2%). 172 cases (27.7%) were with visible abdominal vein, 144 cases (23.2%) with a hard liver texture, and 3.4% (21/620) cases with a hard spleen texture. Abdominal ultrasonography showed that 59.4% (368/620) of the patients were with grade III hepatic fibrosis. 577 cases (93.1%) received medical treatments and 43 cases (6.9%) received surgical treatment. After the treatment, the clinical symptoms and signs of 410 cases (66.1%) were improved and 210 cases (33.9%) needed further treatment., Conclusion: Newly confirmed advanced schistosomiasis patients in Hunan Province are mostly distributed in historically endemic areas, mainly middle-aged and older farmers, and generally in poor health when diagnosed.

Health education is an important component of efforts to control schistosomiasis. In China, while education programmes have been implemented intensively, few articles in recent years in either the Chinese or English literature report randomised, controlled interventions of the impacts on knowledge, attitudes and behaviours. Thus, we designed and carried out a cluster-randomised controlled education intervention trial that targeted 706 adults from rural areas in 28 villages in Sichuan, China. We evaluated the effects of the intervention on five endpoints: (1) schistosomiasis knowledge, (2) attitudes towards infection testing and treatment, (3) use of personal protective equipment (PPE), (4) reducing defecation in the field, and (5) reducing dermal contact with potentially contaminated water sources. The results indicated that people in both the intervention and control groups showed improvement in knowledge, attitudes and reduction in field-defecation in the follow-up surveys. However, there was little evidence that suggested statistically significant differences between the two groups regarding any endpoint. Participation in intervention classes was associated with age, gender, occupation and education level. Our study suggests short-term health education interventions may not be effective in improving schistosomiasis knowledge or in the adoption of health-protective behaviours. This might be partially due to the spontaneous learning process of people subject to repeated surveys and other disease control activities. Considering the difficulties of occupation-associated behaviour change and knowledge reinforcement in general, longer-term education programmes should be considered in the future., (Copyright © 2013 The Authors. Published by Elsevier B.V. All rights reserved.)

Objective: To investigate schistosome infection among the professional fishermen in Yueyang County, East Dongting Lake Region and its influence factors., Methods: A total of 275 fishermen from two fisherman villages in Yueyang County were selected in 2009. They were investigated by fecal examination and questionnairing. The stool-egg positive individuals were detected by B ultrasound. The multivariate unconditional Logistic regression analysis was used to explore the related factors of schistosome infection and liver in fishermen., Results: The total infection rate in fishermen was 40.4% (111/275), and the geometric mean of EPG was 17.4 +/- 4.4. B ultrasound data showed among 111 egg positive individuals, 39 (35.1%) cases manifested as hepatomegaly, 22 (19.8%) had splenomegaly, 11 (9.9%) had portal vein expansion and 65 (58.6%) had hepatic fibrosis. Multivariate unconditional Logistic regression analysis showed that age groups (OR = 0.630), fishing working years (OR = 2.470), chemotherapy frequency (OR = 0.425) and chemotherapy in 2008 (OR = 0.290) were the influence factors on schistosome infection (P < 0.01)., Conclusion: Schistosome infection rate is high, Schistosoma japonicum-induced liver and spleen injuries are still severe in fisherman of Eastern Dongting Lake Region.

To estimate the prevalence of Schistosoma japonicum in field rodents, we conducted surveys of S. japonicum infection on 5 islands in the west Dongting Lake, China: Julinyuan, Jiangjiazui, Longwangmiao, Goutouzhou, and Niujiaojian. Thirty-five Rattus flavipectus, 43 Rattus norvegicus, 42 Rattus rattus , and 48 Microtus fortis were captured and examined from July to August 2011. Schistosoma japonicum was found in the 3 rat species but not in the vole M. fortis . No statistically significant differences in infection rates were found among the 5 locations or the 3 species of Rattus (P > 0.05). The average prevalence in the Rattus species was 14.2% (17/120), revealing that S. japonicum infection within field rodents was widespread in the Dongting Lake region. Wild rodents can be an important reservoir for S. japonicum transmission in the region and are of public health concern.

Schistosomiasis japonica is a major parasitic disease threatening millions of people in China. Though overall prevalence was greatly reduced during the second half of the past century, continued persistence in some areas and cases of re-emergence in others remain major concerns. As many regions in China are approaching disease elimination, obtaining quantitative data on Schistosoma japonicum parasites is increasingly difficult. This study examines the distribution of schistosomiasis in eastern China, taking advantage of the fact that the single intermediate host serves as a major transmission bottleneck. Epidemiological, population-genetic and high-resolution ecological data are combined to construct a predictive model capable of estimating the probability that schistosomiasis occurs in a target area ("spatially explicit schistosomiasis risk"). Results show that intermediate host genetic parameters are correlated with the distribution of endemic disease areas, and that five explanatory variables--altitude, minimum temperature, annual precipitation, genetic distance, and haplotype diversity-discriminate between endemic and non-endemic zones. Model predictions are correlated with human infection rates observed at the county level. Visualization of the model indicates that the highest risks of disease occur in the Dongting and Poyang lake regions, as expected, as well as in some floodplain areas of the Yangtze River. High risk areas are interconnected, suggesting the complex hydrological interplay of Dongting and Poyang lakes with the Yangtze River may be important for maintaining schistosomiasis in eastern China. Results demonstrate the value of genetic parameters for risk modeling, and particularly for reducing model prediction error. The findings have important consequences both for understanding the determinants of the current distribution of S. japonicum infections, and for designing future schistosomiasis surveillance and control strategies. The results also highlight how genetic information on taxa that constitute bottlenecks to disease transmission can be of value for risk modeling.

A Bayesian inference model was introduced to estimate community prevalence of Schistosomiasis japonica infection based on the data of a large-scale survey of Schistosomiasis japonica in the lake region in Hubei Province. A multistage cluster random sampling approach was applied to the endemic villages in the lake regions of Hubei Province in 2011. IHA test and Kato-Katz test were applied for the detection of the S. japonica infection in the sampled population. Expert knowledge on sensitivities and specificities of IHA test and Kato-Katz test were collected based on a two-round interview. Prevalence of S. japonica infection was estimated by a Bayesian hierarchical model in two different situations. In Situation 1, Bayesian estimation used both IHA test data and Kato-Katz test data to estimate the prevalence of S. japonica. In Situation 2, only IHA test data was used for Bayesian estimation. Finally 14 cities and 46 villages from the lake regions of Hubei Province including 50,980 residents were sampled. Sensitivity and specificity for IHA test ranged from 80% to 90% and 70% to 80%, respectively. For the Kato-Katz test, sensitivity and specificity were from 20% to 70% and 90% to 100%, respectively. Similar estimated prevalence was obtained in the two situations. Estimated prevalence among sampled villages was almost below 13% in both situations and varied from 0.95% to 12.26% when only using data from the IHA test. The study indicated that it is feasible to apply IHA test only combining with Bayesian method to estimate the prevalence of S. japonica infection in large-scale surveys.

Due to the life cycle complexity of Schistosoma japonicum and the characteristics of schistosomias is immuno-epidemiology, it is very challenging to give a group of certain rules and thus describe the transmission dynamics of S. japonicum with modelling approaches. Most existing epidemiological models for schistosomias is based on differential equations only track average worm burden without taking into account the individual variations, thus bear limitations on individual infection status monitoring and interpretation. In this paper, an improved stochastic model based on cellular automaton (I-SjCA, briefly) has been introduced to describe the transmission dynamics of human schistosomiasis japonica in an endemic area in China. This model reflects the process of the pathogen invasion from exposure to worm development and worm death when the infection is cleared; it also incorporates seasonality of infection, and stochastic behaviour of each individual in the study field. We show that based on the data collected from the 706 study participants, the model-predicted prevalence and intensity of S. japonicum in the 2nd year of investigation is comparable with the observation. Furthermore, we illustrate the use of model for evaluating possible control strategies for schistosomiasis in context of simulated prevalence and individual infection probability. The simulation results suggest that chemotherapy should cover no less than 85% of the S. japonicum infected population to guarantee an effective drug control program, and the best time for annual chemotherapy with praziquantel is the beginning of spring in the endemic area. Our findings indicate that I-SjCA model based on the cellular automaton can effectively simulate the transmission process. It is anticipated that our cellular automaton transmission model can serve as a tool for understanding schistosomiasis transmission dynamics and thus be conductive to build an effective control program., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Identification of high-risk regions of schistosomiasis is important for rational resource allocation and effective control strategies. We conducted the first study to apply the newly developed method of adaptive kernel density estimation (KDE)-based spatial relative risk function (sRRF) to detect the high-risk regions of schistosomiasis in the Guichi region of China and compared it with the fixed KDE-based sRRF. We found that the adaptive KDE-based sRRF had a better ability to depict the heterogeneity of risk regions, but was more sensitive to altering the user-defined smoothing parameters. Specifically, the impact of bandwidths on the estimated risk value and risk significance (P value) was higher for the adaptive KDE-based sRRF, but lower on the estimated risk variation standard error (s.e.) compared with the fixed KDE-based sRRF. Based on this application the adaptive and fixed KDE-based sRRF have their respective advantages and disadvantages and the joint application of the two approaches can warrant the best possible identification of high-risk subregions of diseases.

Objective: To understand the dynamics of human infection and reinfection of Schistosoma japonicum after chemotherapy in marshland and lake endemic regions so as to provide the evidence for developing a cost-effective control strategy., Methods: From 2007 to 2011, the schistosome infection, intensities and reinfection of population were investigated and the results were analyzed dynamically in Caohui Village, a national schistosomiasis surveillance site in Changyi Township, Xinjian County, Jiangxi Province, China., Results: The schistosome infection rate was 3.55% and the mean intensity was 1.56 in 2007, and the schistosome infection rate was 1.52% and the mean intensity was 1.60 in 2011. The reinfection rates were 2.70%, 9.09% and 2.47% in 2009, 2010, and 2011, respectively., Conclusion: The schistosomiasis endemic situation shows a downtrend in the village. However, the reinfection is still serious; therefore, we should strengthen the research of risk factors of reinfection and control them.

Background: Poyang Lake, the largest fresh water lake in China, is the major transmission site of Schistosoma japonicum in China. Epidemics of schistosomiasis japonica have threatened the health of residents and stunted social-economic development there., Objective: This article aims at evaluating the effect of various control measures against schistosomiasis: selective mass treatment (ST), targeted mass treatment (TT), mass treatment for animal reservoirs (MT), and health education (HE), on reduction of the prevalence through simulations based on a mathematical model., Methods: We proposed a mathematical model, which is a system of ordinary differential equations for the transmission of S. japonicum among humans, bovines, and snails. The model takes into account the seasonal variation of the water level of Poyang Lake that is caused by the backflow of the Yangtze River and inflow from five small rivers, which influences the transmission of S. japonicum. For the purpose of dealing with the age-specific prevalence and intensity of infection, the human population was classified into four age categories in the model. We carried out several simulations resulting from the execution of ST and TT for elementary school children (E Sch), and combinations of ST, MT, and HE., Results: The simulations indicated that all of the control measures only for humans had a trend of revival after interruption, and a combination of ST and MT has a significant effect on reducing human infection. Although TT and HE had a significant effect on the prevalence in the E Sch group, it had little effect on the overall human population., Conclusion: The simulations indicate that measures targeted to bovines such as chemotherapy besides humans will be vital to eliminate the transmission of S. japonicum in the Poyang Lake region. Moreover, it is desirable to improve health education for fishermen and herdsmen., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

Schistosomiasis japonica continues to be an important zoonotic disease in the People's Republic of China (P.R. China), despite decades of dedicated control efforts. Different interventions for its control including chemotherapy of humans and animals, mollusciciding, environmental modification, and health education have been implemented at various stages of the control efforts and in different combinations, resulting in remarkable achievements. Here, we present a systematic review and meta-analysis of the documented effectiveness of health education to reduce schistosomiasis japonica transmission in P.R. China. A total of 10 relevant publications were identified and included in the meta-analysis. The reported results indicate that the prevalence of Schistosoma japonicum infection in humans and schistosomiasis-related knowledge are significantly influenced by health education. The implementation of health education over more than 2 years was associated with an overall schistosomiasis japonica prevalence decrease of 6% (95% CI: 2%, 11%) and an overall increase of 51% (95% CI: 41%, 61%) in schistosomiasis-related knowledge after controlling for confounding factors. Among control groups, the prevalence of schistosomiasis japonica and relevant knowledge levels were not significantly influenced. The relative risk (RR) of an infection with S. japonicum following health education lasting more than 2 years was 0.43 (95% CI: 0.24, 0.78). In summary, a considerable effectiveness of health education with regard to preventing S. japonicum infections in P.R. China and increasing relevant knowledge is documented in the extant literature. This suggests that the effectiveness of health education may be considerable, particularly after its long-term implementation., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

Familial cholesteryl ester transfer protein (CETP) deficiency is more common in some East Asian populations than elsewhere, suggesting the possibility of a selective advantage of this genetic defect against regional infectious diseases. Historically, infection with the Asian blood fluke Schistosoma japonicum has been endemic in these regions, including Japan. We previously reported that eggs of S. japonicum require cholesteryl ester uptake from normal high-density lipoprotein (HDL) but not from CETP-deficient HDL for their maturation to miracidia, a critical step of the hepatic pathogenesis of schistosomiasis. Herein we show that cholesteryl ester uptake is selective from HDL, and identified CD36-related protein (CD36RP) as a candidate to mediate the reaction. CD36RP was cloned from the adult and the egg developmental stages of S. japonicum, with 1880 bp encoding 506 amino acid residues exhibiting the CD36 domains and two transmembrane regions. Using antibodies against recombinant peptides representing the potential extracellular domains of CD36RP, Western blotting detected a protein with a molecular mass of 82 kDa in the particulate fraction of the adult parasite cells, which was reduced to 62 kDa after N-glycanase treatment. The extracellular domain peptide bound human HDL, as established by immunoblots following nondenaturing gel electrophoresis. Antibodies against the extracellular domain suppressed HDL cholesteryl ester uptake and maturation of the eggs in vitro. CD36RP is a candidate receptor on eggs of S. japonicum that facilitates uptake of HDL cholesteryl ester necessary for egg embryonation and maturation.

Schistosomiasis remains a major public health problem with an estimated 200 million people infected in the world, and in China, schistosomiasis japonica is endemic in the south part of the country. In 1960s, before praziquantel was developed, there were about seven million patients. Praziquantel has a high efficacy against Schistosoma, few and transient side effects, simple administration and competitive cost, and is equally suited for both individual and large-scale treatment. Praziquantel has been widely used in the morbidity control, transmission control, and prevention of schistosomiasis japonica in China since 1980s. The schemes of praziquantel chemotherapy include the diagnostic selective chemotherapy, extensive chemotherapy, mass chemotherapy, stratified chemotherapy, phased chemotherapy, etc. Chemotherapy alone or combined with other control measure, such as Oncomelania snail control, health education, safety water supply, and so on, has achieved a great success, and there are only 0.33 million infected people now. This paper reviews the application of praziquantel in the schistosomiasis japonica control strategies in China so as to provide the rich experiences for reference of health workers of other countries where schistosomiasis is endemic.

Objective: To understand the ability of pathogenic diagnosis for schistosomiasis japonica in the national surveillance sites and evaluate the effect of stool hatching method in the field, so as to provide the evidence for establishing a quality control system of pathogenic diagnosis of schistosomiasis in the surveillance sites., Methods: The data pertaining to the parasitological diagnosis of the residents with positive serological tests were collected in 81 national surveillance sites of 12 provinces in 2011, and the effects of the Kato-Katz technique and stool hatching method were evaluated and compared. The incubation quality control samples made by the national schistosomiasis diagnosis reference laboratory were detected by both Kato-Katz technique and stool hatching method using the single-blind method, and the results were analyzed and compared for the coincidence rate, misdiagnosis rate and missing diagnosis rate in all the county laboratories in 2012., Results: A total of 3 780 sero-positive residents were tested by using the Kato-Katz technique and stool hatching method in the 81 national surveillance sites in 2011, 127 persons were double egg-positive, 3 513 persons were double egg-negative, and the total coincidence rate was 96.30%. Totally 173 infected people were diagnosed by using the Kato-Katz technique and the positive detection rate was 4.58%; 221 infected people were diagnosed by using the stool hatching method and the positive detection rate was 5.85%. A total of 267 positive people were diagnosed by the Kato-Katz technique or the stool hatching method or both and the total positive detection rate was 7.06%, which was higher by 54.15% than that by using the single Kato-Katz technique (chi2 = 21.32, P < 0.01). In 2012, of 240 standard incubation quality control samples (160 positives, 80 negatives) detected by the technicians from the 80 surveillance sites, 105 samples were positive and 67 samples were negative, with a total coincidence rate of 71.67% (172/240) and a total missing diagnosis rate of 34.38% (55/160). Among them, the missing rate of the strong positive samples was 32.50% (26/80), the missing rate of the weakly positive samples was 36.25% (29/80), and the misdiagnosis rate of the negative samples was 16.25% (13/80). The detection rates of the incubation quality control samples were 61.11%, 80.00%, 77.08%, 90.48%, 58.33% and 59.26% in the surveillance sites of six provinces, including Anhui, Hubei, Hunan, Jiangsu, Jiangxi and Sichuan provinces, respectively, and a significant difference was found (chi2 = 14.27, P < 0.05)., Conclusions: The detection efficiency of the stool hatching method is superior to that of the Kato-Katz technique in the field. However, the levels of the technical personnel for the stool hatching method are relatively low in most of the surveillance sites. Therefore, the technical training should be strengthened.

Background: The transmission of schistosomiasis japonica in a local setting is still poorly understood in the lake regions of the People's Republic of China (P. R. China), and its transmission patterns are closely related to human, social and economic factors., Methodology/principal Findings: We aimed to apply the integrated approach of artificial neural network (ANN) and logistic regression model in assessment of transmission risks of Schistosoma japonicum with epidemiological data collected from 2339 villagers from 1247 households in six villages of Jiangling County, P.R. China. By using the back-propagation (BP) of the ANN model, 16 factors out of 27 factors were screened, and the top five factors ranked by the absolute value of mean impact value (MIV) were mainly related to human behavior, i.e. integration of water contact history and infection history, family with past infection, history of water contact, infection history, and infection times. The top five factors screened by the logistic regression model were mainly related to the social economics, i.e. village level, economic conditions of family, age group, education level, and infection times. The risk of human infection with S. japonicum is higher in the population who are at age 15 or younger, or with lower education, or with the higher infection rate of the village, or with poor family, and in the population with more than one time to be infected., Conclusion/significance: Both BP artificial neural network and logistic regression model established in a small scale suggested that individual behavior and socioeconomic status are the most important risk factors in the transmission of schistosomiasis japonica. It was reviewed that the young population (≤15) in higher-risk areas was the main target to be intervened for the disease transmission control.

Background: In light of multinational efforts to reduce helminthiasis, we evaluated whether there exist high-risk subpopulations for helminth infection. Such individuals are not only at risk of morbidity, but may be important parasite reservoirs and appropriate targets for disease control interventions., Methods/principal Findings: We followed two longitudinal cohorts in Sichuan, China to determine whether there exist persistent human reservoirs for the water-borne helminth, Schistosoma japonicum, in areas where treatment is ongoing. Participants were tested for S. japonicum infection at enrollment and two follow-up points. All infections were promptly treated with praziquantel. We estimated the ratio of the observed to expected proportion of the population with two consecutive infections at follow-up. The expected proportion was estimated using a prevalence-based model and, as highly exposed individuals may be most likely to be repeatedly infected, a second model that accounted for exposure using a data adaptive, machine learning algorithm. Using the prevalence-based model, there were 1.5 and 5.8 times more individuals with two consecutive infections than expected in cohorts 1 and 2, respectively (p<0.001 in both cohorts). When we accounted for exposure, the ratio was 1.3 (p = 0.013) and 2.1 (p<0.001) in cohorts 1 and 2, respectively., Conclusions/significance: We found clustering of infections within a limited number of hosts that was not fully explained by host exposure. This suggests some hosts may be particularly susceptible to S. japonicum infection, or that uncured infections persist despite treatment. We propose an explanatory model that suggests that as cercarial exposure declines, so too does the size of the vulnerable subpopulation. In low-prevalence settings, interventions targeting individuals with a history of S. japonicum infection may efficiently advance disease control efforts.

Objective: To evaluate the field application of IHA and ELISA for schistosomiasis japonica detection at low transmission status., Methods: 728 and 799 persons were examined by Kato-Katz's method, IHA and ELISA for schistosomiasis in an endemic village in the year of 2008 and 2010, respectively. The results of IHA and ELISA was evaluated in comparison to that of Kato-Katz (27 slides with 3 stool specimens) used as gold standard., Results: The positive rate of Kato-Katz's method, IHA and ELISA were 10.3% (75/728), 40.0% (291/728) and 40.1% (292/728) in 2008, and 3.8% (30/799), 31.5% (252/799) and 40.1% (320/799) in 2010 respectively, in which significant difference was observed for the result between Kato-katz's method (chi2 = 26.92, P < 0.05) and IHA (chi2 = 11.82, P < 0.05). The consistency between the result of antibody detection and that of Kato-Katz's method was poor, lower than 0.2 (P < 0.01). If routine screening diagnosis mode was adopted, namely, population screened with IHA or ELISA first and confirmed with Kato-Katz's method, correlation analysis showed that the positive rate of Kato-Katz's method increased with the number of stool specimens and slides (rIHA2008 = 0.922, rELISA2008 = 0.908, rIHA2010 = 0.749, rELISA = 0.798; P < 0.05) . Those with egg positive but missed by IHA or ELISA mainly were cases with low infection intensity. When EPG < or = 40, the rate of detection ranged from 66.1% (39/59) to 87.0% (20/23) with IHA, and 62.7% (37/59) to 100% (23/23) with ELISA. When EPG > 40, however, all cases could be detected with ELISA, but some missed with IHA., Conclusion: In low transmission areas, the determination of target population for chemotherapy should be based on the examination of nine slides per stool specimen by Kato-Katz's method after serological screening.

Objective: To analyze the impact of large hydraulic projects on schistosomiasis transmission and evaluate the transmission risk in potential endemic areas., Methods: 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., Results: 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, P > 0.05). 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., Conclusion: 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.

Over the past decades China has made a great stride in controlling schistosomiasis, eliminating transmission of Schistosoma japonicum in 5 provinces and remarkably reducing transmission intensities in the rest of the seven endemic provinces. Recently, an integrated control strategy, which focuses on interventions on humans and bovines, has been implemented throughout endemic areas in China. This strategy assumes that a reduction in transmission of S. japonicum from humans and bovines to the intermediate Oncomelania snail host would eventually block the transmission of this parasite, and has yielded effective results in some endemic areas. Yet the transmission of S. japonicum is relatively complicated--in addition to humans and bovines, more than 40 species of mammalians can serve as potential zoonotic reservoirs. Here, we caution that some factors--potential roles of other mammalian reservoirs and human movement in sustaining the transmission, low sensitivity/specificity of current diagnostic tools for infections, praziquantel treatment failures, changes in environmental and socio-economic factors such as flooding in key endemic areas--may pose great obstacles towards transmission interruption of the parasite. Assessing potential roles of these factors in the transmission and implications for current control strategies aiming at transmission interruption is needed.

Objective: To understand the endemic situation dynamics of schistosomiasis in domestic animals (mainly bovine) in mountainous endemic regions, so as to provide the reference for evaluating the control effect and improving control strategy., Methods: Two representative pilots (Renmei and Dacang) in mountainous schistosomiasis endemic regions were selected for survey. The schistosome infection status of bovine was investigated by the miracidium hatching method, the pasture of bovine were investigated by home visiting, and the distributions of wild feces and Oncomelania snails, and the snail schistosome infection status were also investigated in April and September every year., Results: The schistosome infection rates of bovine reduced by 98.4% and 93.8% in two pilots in 2007 compared with those in 1993, and the infection intensities also showed a decline trend. The infection rate of wild faces was 0 in Renmei pilot since 1995, while in Dacang pilot, the infection rate of wild feces fluctuated in 2007, and the intensities of living snails and infected snails showed a declined trend., Conclusions: Due to the special natural environment of mountainous endemic regions, there is a dot-like or band-like distribution of endemic areas. The strengthening of schistosomiasis examination and chemotherapy will rapidly reduce endemic situation. However, to completely interrupt the transmission of schistosomiasis, we should emphasize environmental modification and domestic animal management.

This report overviewed the national endemic status of schistosomiasis in People's Republic of China in 2011. By the end of 2011, a total of 286 836 cases of schistosomiasis japonica were estimated with a decrease rate of 11.97% compared with the number in 2010. A total of 3 acute cases were reported, decreased by 93.02% compared to the number in 2010. A total of 22 519 advanced cases were treated in 2010, increased by 10.34% compared to that in 2010. About 372 664.10 hm2 of areas infested with Oncomelania snail were found in 2011, and about 1 163.87 hm2 newly detected areas were reported. There were 1 410 936 cattle raised in schistosomiasis transmission regions in 2011. The infection rate of cattle was 0.68% in 2011, with a reduction rate of 34.62% comparing to that in 2010 (1.04%).

Sensitive Schistosoma japonicum detection methods are needed to progress from schistosomiasis control to elimination. The sensitivity of the Kato-Katz thick smear and miracidium hatching tests decrease with infection intensity and serological tests cannot always identify current infections. We evaluated a fecal polymerase chain reaction (PCR) assay to detect S. japonicum infection in 106 humans and 8 bovines in China. PCR was highly sensitive, detecting S. japonicum DNA at 0.5 eggs/g of stool. Comparing PCR examination of a single stool sample to the miracidium hatching test using three consecutive stool samples, more humans were hatching test positive (20%) than PCR positive (15%). However, two individuals were PCR positive in a village where no infections were detected by coprological methods. The sensitivity of PCR makes it a promising tool for schistosomiasis diagnostics and screening, although egg shedding variability and stool sample size present challenges for any detection method in low-transmission areas.

Objective: To understand the endemic situation of national surveillance sites in Jiangsu Province from 2005 to 2010, so as to provide the evidence for the prevention and control of schistosomiasis., Methods: According to the national surveillance protocol, a longitudinal surveillance on endemic situation of schistosomiasis was carried out in 8 national surveillance sites from 2005 to 2010., Results: In general, the positive rates of blood tests and infection rates of Schistosoma japonicum decreased from 9.04% and 0.22% in 2005 to 4.34% and 0.02% in 2010, and the rates of decline were 51.99% and 90.91%, respectively. The endemic situation of farmers, fishermen and business men were relatively serious, and the infection degree of the low-aged group of students was relatively serious. No local acute schistosomiasis case was detected. A total of 7 466.46 hm2 of environmental sites were investigated, and the areas with living Oncomelania hupensis snails and infected snails were 2 213.98 and 247.91 hm2, respectively, the densities of living snails and infected snails decreased gradually, and no infected snail was found in 2010. However, the total areas with living snails and infected snails still keep a relative high level, and the density of infected snails rebounded in special sites., Conclusion: The endemic situation of the national surveillance sites is under control, and the infection rate of human keeps at a low level in Jiangsu Province. The surveillance and control of snails and infection source should still be strengthened.

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 compare the sensitivities of different isolates of Schistosoma japonicum in marshland and lake regions of Chinese Mainland to praziquantel, so as to provide experimental evidence for establishing the techniques of detecting and monitoring praziquantel sensitivity., Methods: Mice were infected with cercariae released from the S. japonicum-infected snails collected from the marshland and lake endemic regions of Hunan, Hubei, Jiangxi, Anhui and Jiangsu provinces, grouped, and treated with praziquantel at single oral doses of 37.5, 75, 150, 300 mg/kg and 600 mg/kg, while mice infected but treated with 2.5% Cremophor EL served as controls. The worm burden reductions caused by praziquantel treatment were observed, and the 50% effective dose (ED50 value) was calculated., Results: The administration with praziquantel at single oral doses of 37.5, 75, 150, 300 mg/kg and 600 mg/kg achieved worm burden reductions of 10.37%-19.81%, 23.22%-33.09%, 39.25%-49.61%, 62.87%-74.44% and 91.26%-98.09%, respectively, and no significant differences in worm burden reductions of different isolates of S. japonicum were detected following treatment with different doses of praziquantel (P > 0.05). The praziquantel ED50 values against different isolates of S. japonicum ranged from 134.1 to 186.7 mg/kg, and no significant differences of praziquantel ED50 values were found among different isolates (P > 0.05)., Conclusions: There were no significant differences of praziquantel sensitivities of different isolates of S. japonicum in marshland and lake regions of Chinese Mainland. Praziquantel ED50 value against schistosomes, as a quantitative index, can truly reflect the sensitivity of schistosome populations to praziquantel, which can be used to assess the risk of emergence of praziquantel resistance in schistosomes.

In 2009, Wang et al.'s field trial published in the New England Journal of Medicine, reported that a comprehensive strategy aiming to reduce the roles of humans and cattle as sources of Schistosoma japonicum infection in snails was implemented and proved effective and promising in dramatically reducing the percentage of infected humans and snails, which had been extended to other endemic provinces in China afterwards. This implies that the integrated schistosomiasis-control strategies of interventions including political will, financial support and residents' participation to control human and bovine sources of S. japonicum infection in snails may direct to successfully interrupt the parasitic transmission and to ultimately eliminate schistosomiasis. Confusingly, however, the role of health education, which is a critical part of the integrated strategy and should play an active role in schistosomiasis control, was not reflected. We wish the authors to provide the readers a better and clearer statement of the role of health education as part of the integrated control strategy and so we write this comment.

The purpose of the current study was to investigate the susceptibility of Schistosoma japonicum to praziquantel in low endemic foci of China. During the non-transmission period of schistosomiasis, a total of 43 of 1,242 subjects were identified as being infected with the parasite using parasitological stool examinations in two low-endemicity areas of China, with a prevalence rate of 3.46%. All stool-egg-positive subjects were treated with praziquantel in a single oral dose of 40 mg/kg or 30 mg/kg for two successive days. Six weeks post-treatment, no S. japonicum eggs were detected in the 43 treated villagers. The results indicate that the current efficacy of praziquantel against S. japonicum seems satisfactory and has not changed over the past three decades in the low endemic areas of China. It is also suggested that no evidence of tolerance or resistance to praziquantel in S. japonicum is detected in areas with low endemicity in China.

Objective: To obtain promising antigens for diagnosis or therapeutic efficacy assessment of schistosomiasis japonica., Methods: At an endemic area in Anqing of Anhui Provinces, Kato-Katz method (six slides from two consecutive stool samples) was used to examine schistosome eggs and serum samples of 10 egg-positive patients were collected. The EPG of the ten patients, aged 13 to 64, was among 4 to 172. The patients were then treated with praziquantel 60 mg kg for two days. Sera of the same patients were collected again at six months post treatment. The egg cDNA library was immunoscreening with the pre- and post-treatment serum samples, and the positive clones were classified according to different reactions. The inserted fragments of positive clones were sequenced and analyzed for their homology through BLAST program. The amino acid sequences of the proteins were deduced from the gene sequences, and their structures and functions were predicted by bioinformatics tools., Results: For the first round, 75 positive clones were screened from the egg cDNA library. Among them, 21 clones showed stronger reaction with the pre-treatment sera, and 8 clones showed stronger reaction with the post-treatment sera. According to the intensity of the reaction, types and the length of inserted fragments, 14 positive clones were selected for further study. Most of the clones belonged to miracidial antigen family, one clone was significantly homologous to the calcium-binding EF-hand, a domain-containing protein (score = 143), one was highly homologous to the cell wall integrity and stress response component 1 precursor (score = 487), and another four were homologous to the hypothetical protein., Conclusion: Twenty nine positive clones screened from the egg cDNA library show different reactions with the sera of schistosome-infected patients, before and after praziquantel treatment.

Artesuante (AS) is a good chemoprophylactic drug for preventing against schistosome infection, but Hua et al. recently reported that the sensitivity of AS against Schistosoma japonicum decreased after 10 years of use in China. There are at least three problems, to our knowledge, making the finding suspicious or inconclusive in that report. In consideration of it as the first report about the emergence of potential artemisinin derivative-resistant S. japonicum to date and the possible severe influences of the emergence of AS-resistant S. japonicum on the future choice of chemoprophylactic drugs for preventing against S. japonicum infections in China, we write this comment and call for some more rigorous and convincing trials to confirm this finding further.

Currently schistosomiasis transmission has been suppressed to low levels in many historically endemic areas of China by widespread use of praziquantel in human and bovine populations and application of niclosamide for snail control. However, re-emergent transmission has signalled the need for sustainable interventions beyond these repeated chemical interventions. To take advantage of ongoing investment in rural infrastructure, an index of schistosomiasis transmission potential is needed to identify villages where environmental modifications would be particularly effective. Based on a retrospective analysis of data from 10 villages in Sichuan Province, an index linked to the basic reproductive number is shown to have promise in meeting this need. However, a lack of methods for estimating the spatial components of the proposed metric and for estimating the import of cercariae and miracidia from neighbouring villages leads to significant uncertainty in its estimation. These findings suggest a priority effort to develop methods for measuring the free-swimming forms of the parasite in surface waters. This need is underscored by the high cost and limited sensitivity of current methods for diagnosing human infection and mounting evidence of the inadequacy of snail surveys to identify environments supporting low levels of transmission.

This article describes the main approach of ecological civilization construction and great changes and achievements in the original schistosomiasis endemic areas, Yujiang County, Jiangxi Province. Ecological civilization is an important part of schistosomiasis control work.

From 2005 to 2010, the infection rates of schistosomiasis among residents (above 6 years old) were 13.34%, 9.59%, 4.81%, 3.03%, 2.35% and 2.19%, respectively. The positive rates of schistosomiasis among domestic animals fluctuated from 2.50% to 25.92%. Oncomelania snails were not found inside embankment since 1980, yet a high density of infected snails was found at low and uneven areas outside embankment. The cattle were the main infectious source and we should strengthen the administration and control of cattle.

Objective: To explore the socioeconomic determinants of chronic schistosomiasis japonica at a community (village) level., Methods: The socioeconomic and epidemiological data (Years lived with disability, YLDs) came from the thematic research carried out in two schistosome-endemic counties, Dangtu and Hanshou, in lake areas between 2004 and 2005. A concentration index was calculated and used to assess the health inequalities between socioeconomic statuses. The community risk factors relating to chronic schistosomiasis were explored by the multiple regression model., Results: The concentration index was -0.12 of Dangtu County and 0.03 of Hanshou County which indicated that there were no health inequalities due to schistosomiasis between communities with different socioeconomic statuses. There was no linear relationship between the economic levels and YLDs of chronic schistosomiasis. The results of multiple regression model showed that the distance from village to schistosome-infested water (P < 0.01) and wet land area per capita (P < 0.05) were significantly related to YLDs of chronic schistosomiasis., Conclusion: There is non-linear relationship between socioeconomic levels and YLDs of chronic schistosomiasis, but the distance from village to schistosome-infested water and wet land area per capita are significantly related to the latter.

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

Objective: To explore the spatial distribution and pattern of advanced schistosomiasis in Anxiang County so as to provide the evidence for improving advanced schistosomiasis control., Methods: Based on the geographic database of advanced schistosomiasis distribution at the village level in Anxiang County, Hunan Province, the spatial autocorrelation analysis and spatial scan statistics were applied to analyze the spatial characteristics of distribution of advanced schistosomiasis., Results: The global Moran's I of prevalence rate of advanced schistosomiasis was 0.06 (P > 0.05) and there was no spatial auto-correlation as a whole. The local spatial auto-correlation analysis showed that there were 9 villages with statistically significant LISA value (P < 0.05), among which existed high-high, low-high and high-low types of auto-correlation model. The results of SaTScan statistics was the same as local spatial auto-correlation analysis and showed the existence of one cluster area., Conclusions: There are local spatial auto-correlation and spatial aggregation of advanced schistosomiasis in Anxiang County. According to the distribution characteristics, we can assign resource more reasonably and control schistosomiasis more effectively.