Diagnostic performance of two specific schistosoma japonicum immunological tests for screening schistosoma haematobium in school children in Zambia.

Dipstick Dye Immunoassay (DDIA) and Indirect Haemagglutination Assay (IHA), are two commercially available kits which have been widely used for screening Schistosoma japonicum in P.R. China. Whether they can be used for screening of Schistosoma haematobium are not clear. In order to evaluate the diagnostic efficiency of DDIA and IHA for screening Schistosoma haematobium, serum samples were collected from pupils in endemic areas in Zambia, Southern Africa, and tested by DDIA and IHA by single-blind manner. Meanwhile, the pupils were microscopically examined by infection with Schistosoma and soil-transmitted helminths, visually observed for parasite eggs. Of the enrolled 148 pupils, 61% tested positive for S. haematobium infection, while 31% and 36% of pupils were infected with hookworm and Ascaris respectively. Regarding the parasitological tests as reference standard, for the diagnosis of S. haematobium infection, IHA performed higher sensitivity (74%, 95% CI: 65%-83%) than that of DDIA (60%, 95%CI: 49%-70%). The sensitivities of IHA and DDIA are significant higher in 10-14 years old students than those of 7-9 years old group. The specificity of DDIA and IHA were 61% (95%CI: 49%-74%) and 72% (95%CI: 60%-84%), respectively. The co-infection with STHs decreased the specificity of DDIA but had no impact on that of IHA. Our study indicated that IHA has more potential as an alternative diagnostic tool for identifying schistosomiasis haematobium but need further improvement.

Corrections to: Molluscicidal effectiveness of Luo-Wei, a novel plant-derived molluscicide, against Oncomelania hupensis, Biomphalaria alexandrina and Bulinus truncatus.

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Molluscicidal effectiveness of Luo-Wei, a novel plant-derived molluscicide, against Oncomelania hupensis, Biomphalaria alexandrina and Bulinus truncatus.

BACKGROUND: Control of snail intermediate hosts has been proved to be a fast and efficient approach for interrupting the transmission of schistosomiasis. Some plant extracts have shown obvious molluscicidal activity, and a new compound Luo-Wei, also named tea-seed distilled saponin (TDS), was developed based on the saponins extracted from Camellia oleifera seeds. We aimed to test the molluscicidal activity of 4% TDS against the intermediate host snails in China and Egypt, and evaluate its environmental safety to non-target organisms. METHODS: In the laboratory, Oncomelania hupensis, Biomphalaria alexandrina and Bulinus truncatus were exposed to 4% TDS, and the median lethal concentration (LC50) was estimated at 24, 48 and 72 h. In the field, snail mortalities were assessed 1, 2, 3 and 7 d post-immersion with 2.5 g/m3 4% TDS and 1, 3, 7 and 15 d post-spraying with 5 g/m2 4% TDS. In addition, the acute toxicity of 4% TDS to Japanese quail (Coturnix japonica), zebrafish (Brachydanio rerio) and freshwater shrimp (Macrobrachium nipponense) was assessed by estimations of LC50 or median lethal dose (LD50). RESULTS: In the laboratory, the LC50 values of 4% TDS for O. hupensis were 0.701, 0.371 and 0.33 mg/L at 24, 48 and 72 h, respectively, and 4% TDS showed a 1.975 mg/L [corrected] 24 h LC50 against B. alexandrina, and a 1.396 mg/L 24 h LC50 against B. truncatus. Across all study regions, the pooled mortalities of O. hupensis were 72, 86, 94 and 98% at 1, 2, 3 and 7 d, following field immersion of 4% TDS at a dose of 2.5 g/m3, and were 69, 77, 85 and 88% at 1, 3, 7 and 15 d, following field spraying at 5 g/m2, respectively. 4% TDS had moderate toxicity to Japanese quail (7 d LD50 > 60 mg/kg) and to shrimp (96 h LC50 = 6.28 mg/L; 95% CI: 3.53-11.2 mg/L), whereas its toxicity to zebrafish was high (96 h LC50 = 0.15 mg/L; 95% CI: 0.14-0.17 mg/L). CONCLUSIONS: 4% TDS is active against O. hupensis, B. alexandrina and B. truncatus under laboratory and field conditions, and it may be a candidate molluscicide of plant origin.

SUMOylation of Alpha-Synuclein Influences on Alpha-Synuclein Aggregation Induced by Methamphetamine.

Methamphetamine (METH) is an illegal and widely abused psychoactive stimulant. METH abusers are at high risk of neurodegenerative disorders, including Parkinson's disease (PD). Previous studies have demonstrated that METH causes alpha-synuclein (α-syn) aggregation in the both laboratory animal and human. In this study, exposure to high METH doses increased the expression of α-syn and the small ubiquitin-related modifier 1 (SUMO-1). Therefore, we hypothesized that SUMOylation of α-syn is involved in high-dose METH-induced α-syn aggregation. We measured the levels of α-syn SUMOylation and these enzymes involved in the SUMOylation cycle in SH-SY5Y human neuroblastoma cells (SH-SY5Y cells), in cultures of C57 BL/6 primary mouse neurons and in brain tissues of mice exposure to METH. We also demonstrated the effect of α-syn SUMOylation on α-syn aggregation after METH exposure by overexpressing the key enzyme of the SUMOylation cycle or silencing SUMO-1 expression in vitro. Then, we make introduced mutations in the major SUMOylation acceptor sites of α-syn by transfecting a lentivirus containing the sequence of WT α-syn or K96/102R α-syn into SH-SY5Y cells and injecting an adenovirus containing the sequence of WT α-syn or K96/102R α-syn into the mouse striatum. Levels of the ubiquitin-proteasome system (UPS)-related makers ubiquitin (Ub) and UbE1, as well as the autophagy-lysosome pathway (ALP)-related markers LC3, P62 and lysosomal associated membrane protein 2A (LAMP2A), were also measured in SH-SY5Y cells transfected with lentivirus and mice injected with adenovirus. The results showed that METH exposure decreases the SUMOylation level of α-syn, although the expression of α-syn and SUMO-1 are increased. One possible cause is the reduction of UBC9 level. The increase in α-syn SUMOylation by UBC9 overexpression relieves METH-induced α-syn overexpression and aggregation, whereas the decrease in α-syn SUMOylation by SUMO-1 silencing exacerbates the same pathology. Furthermore, mutations in the major SUMOylation acceptor sites of α-syn also aggravate α-syn overexpression and aggregation by impairing degradation through the UPS and the ALP in vitro and in vivo. These results suggest that SUMOylation of α-syn plays a fundamental part in α-syn overexpression and aggregation induced by METH and could be a suitable target for the treatment of neurodegenerative diseases.

Approaches being used in the national schistosomiasis elimination programme in China: a review.

Schistosomiasis japonica, caused by the human blood fluke Schistosoma japonicum, remains a major public health problem in China, although great success has been achieved. The control efforts during the past half-decade, notably the wide implementation of the new integrated strategy with emphasis on control of the source of S. japonicum infection across the country since 2004, has greatly reduced S. japonicum in humans, livestock, and intermediate host Oncomelania hupensis snails, and transmission control of schistosomiasis was achieved in China in 2015. A two-stage roadmap was therefore proposed for schistosomiasis elimination in 2015, with aims to achieve transmission interruption by 2020 and achieve disease elimination by 2025 in the country. During the last two decades, a variety of approaches, which target the epidemiological factors of schistosomiasis japonica have been developed, in order to block the transmission cycle of the parasite. These approaches have been employed in the national or local schistosomiasis control activities, and facilitated, at least in part, the progress of the schistosomiasis elimination programs. Here, we present an approach to control the source of S. japonicum infection, three new tools for snail control, three approaches for detecting and monitoring S. japonicum infection, and a novel model for health education. These approaches are considered to play a great role in the stage moving towards transmission interruption and elimination of schistosomiasis in China.

An integrated environmental improvement of marshlands: impact on control and elimination of schistosomiasis in marshland regions along the Yangtze River, China.

BACKGROUND: Schistosomiasis is a global snail-transmitted infectious disease of poverty. Transmission control had been achieved in China in 2015 after the control efforts for over 60 years. Currently, the remaining core regions endemic for Schistosoma japonicum are mainly located in the marshland and lake regions along the Yangtze River basin. METHODS: During the period from 2001 through 2015, an integrated environmental improvement of the marshlands was carried out through the implementation of industrial, agricultural and resources development projects in Yizheng County along the Yangtze River. S. japonicum infection in humans, livestock and snails was estimated by serology, stool examination, hatching technique and microscopy during the 15-year study period to evaluate the effect of the integrated environmental improvement on control and elimination of schistosomiasis. RESULTS: A 0.05% overall rate of S. japonicum infection was observed in snails during the 15-year study period, and no infected snails were detected since 2012. The overall prevalence of S. japonicum infection was 0.09% in humans during the study period, and no human infection was found since 2012. In addition, only 13 bovines were identified with S. japonicum infection in 2003 during the 15-year study period, and since 2004, no infection was found in livestock. CONCLUSION: The results of the present study demonstrate that the implementation of industrial, agricultural and water resources development projects, not only alters snail habitats in marshland regions, and promotes local economic development, which appears a win-to-win strategy to block the transmission of S. japonicum and accelerate socio-economic development along the Yangtze River.

A multidisciplinary, integrated approach for the elimination of schistosomiasis: a longitudinal study in a historically hyper-endemic region in the lower reaches of the Yangtze River, China from 2005 to 2014.

BACKGROUND: Although great success has been achieved, schistosomiasis remains a major public health concern in China, and the remaining core endemic regions are concentrated along the middle and lower reaches of the Yangtze River. In this longitudinal study, we evaluated the effectiveness of a multidisciplinary, integrated approach for schistosomiasis elimination in a historically hyper-endemic region in the lower reaches of the Yangtze River, China over the 10-year period from 2005 through 2014. METHODS: A three-step roadmap for schistosomiasis elimination was designed in the study site, and multidisciplinary, integrated interventions were implemented by the health, agriculture, water resources development, land and resources, and forestry sectors from 2005 to 2014, including chemotherapy for infected individuals, health education, management of the source of Schistosoma japonicum infection, and intermediate host snail control. The annual number of schistosomiasis patients, S. japonicum infection in humans, bovines and Oncomelania hupensis snails, and water infectivity were observed to assess the effectiveness of the multidisciplinary, integrated approach for the elimination of schistosomiasis. RESULTS: There was a tendency towards a gradual decline in both the number of schistosomiasis cases and the prevalence of S. japonicum human infection across the study period from 2005 through 2014. No S. japonicum human infection was detected since 2012, and no acute infection was seen since 2006. During the study period, no infection was found in bovines, and a 0.03% overall infection rate was observed in O. hupensis snails. Since 2009, no infected snails were identified, and the area of both snail habitats and infected snail habitats appeared a reduction over the study period. Following the 3-year multidisciplinary, integrated control, infection control was achieved, and transmission control was achieved after 6-year implementation, with all infected snails and water infectivity eliminated; in addition, the 10-year implementation resulted in interruption of schistosomiasis transmission in the study site in 2014. CONCLUSIONS: The results of the present 10-year longitudinal study demonstrate that the multidisciplinary, integrated approach is effective for the elimination of schistosomiasis as a public health problem in the lower reaches of the Yangtze River, China.

[Integration and demonstration of key techniques in surveillance and forecast of schistosomiasis in Jiangsu Province III Development of a machine simultaneously integrating mechanized environmental cleaning and automatic mollusciciding].

OBJECTIVE: To develop a machine simultaneously integrating mechanized environmental cleaning and automatic mollusciciding and to evaluate its effectiveness of field application, so as to provide a novel Oncomelania hupensis snail control technique in the large-scale marshlands. METHODS: The machine simultaneously integrating mechanized environmental cleaning and automatic mollusciciding, which was suitable for use in complex marshland areas, was developed according to the mechanization and automation principles, and was used for O. hupensis snail control in the marshland. The effect of the machine on environmental cleaning and plough was evaluated, and the distribution of living snails was observed at various soil layers following plough. The snail control effects of plough alone and plough followed by mollusciciding were compared. RESULTS: The machine could simultaneously complete the procedures of getting vegetation down and cut vegetation into pieces, plough and snail control by spraying niclosamide. After plough, the constituent ratios of living snails were 36.31%, 25.60%, 22.62% and 15.48% in the soil layers at depths of 0-5, 6-10, 11-15 cm and 16-20 cm respectively, and 61.91% living snails were found in the 0-10 cm soil layers. Seven and fifteen days after the experiment, the mortality rates of snails were 9.38% and 8.29% in the plough alone group, and 63.04% and 80.70% in the plough + mollusciciding group respectively (χ²7 d = 42.74, χ²15 d = 155.56, both P values < 0.01). Thirty days after the experiment, the densities of snails were 3.02 snails/0.1 m² and 0.53 snails/ 0.1 m² in the soil surface of the plough alone group and the plough + mollusciciding group, which decreased by 64.92% and 93.60%, respectively, and the decrease rate of snail density was approximately 30% higher in the plough + mollusciciding group than that in the plough alone group. CONCLUSIONS: The machine simultaneously integrating mechanized environmental cleaning and automatic mollusciciding achieves the integration of mechanical environmental cleaning and automatic niclosamide spraying in the complex marshland areas, which provides a novel technique of field snail control in the large-scale setting in China.

[Integration and demonstration of key techniques in surveillance and forecast of schistosomiasis in Jiangsu Province I Layout and effect of the demonstration sites for schistosomiasis surveillance and forecast].

OBJECTIVE: To explore and integrate the key techniques used in the surveillance and forecast of schistosomiasis in the water regions along the Yangtze River, so as to provide technical support for identifying rapidly the risk of schistosomiasis transmission and implementing control measures targeting the risk. METHODS: According to the distribution of water systems and water regions along the Yangtze River in Jiangsu Province, the demonstration sites for surveillance and forecast of schistosomiasis were set across the province, where the integration and demonstration of the techniques regarding monitoring of Schistosoma japonicum infection in sentinel mice, human and animal activities, release of forecast information, and emergency treatment of water regions at risk of infection were performed. The pattern of human and animal activities was compared with the S. japonicum infection in sentinel mice in the demonstration sites, and the operability of the release of information and emergency treatment of the risk of S. japonicum infection was evaluated. RESULTS: A total of 50 demonstration sites for surveillance and forecast of schistosomiasis were set in fixed anchor points, opening of the navigation lock to the Yangtze River, freight terminal, agritainment places, ferry, large construction places, and places for guaranteeing the Youth Olympic Games in 23 counties (districts) of 5 cities, Jiangsu Province. During the period between May. and September, 2014, the infectivity of water body was monitored by using 5 batches of sentinel mice, with a 99.06% (4,954/5,001) gross recovery rate of mice. S. japonicum infection was detected in a demonstration site, and an infected mouse was found, with a 0.02% (1/4,933) gross positive rate of sentinel mice. The field survey showed 2 088 person-times contacting water, including 91.95% (1,920/2,088) contacting water due to the production such as capturing fish, harvesting and cultivating crops, and repairing and building boats, and 8.05% (168/2 088) contacting water due to the life activity, such as fishing, washing vegetables and playing with water. The people contacted water predominantly in August and September (49.57%). A total of 859 boats containing 1,877 boatmen were observed, 68.22% (586/859) of which were fishing boats containing 1,306 fishermen (69.58%). There were 32 sheep found in 4 demonstration sites, and 3 sheep were seen in the demonstration site with infected sentinel mouse. Four blue forecasts (emergence of water contact) and one orange forecast (S. japonicum-infected sentinel mouse detected) were released across the province, with one forecast map released which showed 5 sites with fishing and one site with sheep grazing, one emergency response system initiated, mollusciciding implemented in 10 hm2 high-risk regions, 120 sheep grazed in fence, and 35 fishermen given health-education materials, schistosomiasis examination and preventive therapy. In addition, no acute schistosomiasis occurred in the demonstration site with S. japonicum-infected sentinel mice. CONCLUSIONS: The integration and demonstration of the techniques regarding monitoring of S. japonicum infection in sentinel mice, human and animal activities, release of forecast information, and emergency treatment of water regions at risk of infection provides an effective approach for the large-scale surveillance and forecast of schistosomiasis.

[Effect of mid- and long-term schistosomiasis control plan and discussion of consolidation strategy in marshland endemic regions].

OBJECTIVE: To evaluate the effectiveness of mid- and long-term schistosomiasis control plan and explore the consolidation strategy in marshland endemic regions, so as to provide an effective approach for interrupting and eliminating schistosomiasis in the regions. METHODS: A prospective field study was designed. Dantu District of Zhenjiang City, a marshland schistosomiasis endemic region, was selected, and the "key village, key environment, and key water regions" comprehensive control strategy was implemented according to the endemic level of schistosomiasis. The morbidity due to schistosomiasis in humans and domestic animals, and Oncomelania hupensis snails were surveyed, and the data of the implementation of control measures were collected. The schistosomiasis morbidity and snail status were compared before and after the implementation of the mid- and long-term plan for schistosomiasis prevention and control, and the changing trends of human, domestic animal and snail infections were plotted. RESULTS: During the implementation of the plan from 2005 to 2014, 16.84 km concrete and bank protection and 9 snail sinks were built, 10 culverts re-built, 3.85 hm2 fences were constructed, 29.5 thousand domestic animals were examined and treated, 170 cattle were eliminated, 4930 hm2 fishing farms were built for snail control, 1 560.00 hM2 land were improved, and 376.00 hm2 forests were built for snail control. In addition, 19,364.80 hm2 snail areas were surveyed, 4694.6 hm2 area received molluscicide, 207.9 thousand of people (person-times) received the examination and treatment, 69.1 thousand of harmless toilets were built, 282.2 thousand health education materials and protection materials were allocated, 958 warning signs were established, and 5435 slogans were pasted or hung. After the implementation of the mid- and long-term plan, the percentages of human, bovine and snail infections appeared decline tendencies year by year, and reduced from 0.08%, 1.28% and 0.13% in 2005 to 0 in 2014, respectively, while the areas with snails and infected snails reduced from 284.34 hm2 and 55.10 hm2 in 2005 to 73.60 hm2 and 0 hm2 in 2014, with reduction rates of 74.12% and 100%, respectively. The infection rate of sheep appeared a fluctuation between 2005 and 2014, with the rate of 1.13% in 2005, 0 in 2007 and 2008, rising in 2009 and then between 0.25% and 0.95% from 2009 to 2012, and reducing to 0 in 2013 and 2014. During the 10-year period, the number of cattle reduced year by year from 2005 to 2010, and slightly increased after 2011, showing an overall stable level, while the number of sheep increased year by year after 2006, peaked in 2010, and appeared a decline tendency since 2011, which was almost consistent with the fluctuation of schistosome infection rate in sheep. CONCLUSIONS: The sustainable comprehensive control strategy with the "key village, key environments, and key water regions" is an effective approach for schistosomiasis control in marshland endemic regions. However, the endemic situation of schistosomiasis is extremely easy to repeat. The prevention and control of the impact of sheep and wild animals on schistosomiasis transmission should be strengthened in order to consolidate the schistosomiasis control achievements gained.

[Appropriate technology: a driver to eliminate schistosomiasis in China. In- sights gained from the First Forum on Schistosomiasis Control in China].

This paper described the First Forum on Schistosomiasis Control in China. With "Appropriate technology is essential to schistosomiasis prevention and control" as the topic, the forum shared the main interventions and experiences for schistosomiasis control and elimination, exhibited the recent achievements gained from the development of appropriate technology for schistosomiasis control, showed the technical support of appropriate technology for schistosomiasis elimination, and proposed the priority for the future research and development of appropriate technology for schistosomiasis control and elimination in China. It is considered that the forum builds a bridge for communicating information between the administrative sectors and specialized prevention and control institutions, between research institutions and manufactures, and between experts/professors and grassroots professional staff, and provides a platform to communicate the national schistosomiasis control knowledge of China.

[Integration and demonstration of key techniques in the surveillance and forecast of schistosomiasis in Jiangsu Province II Molluscicidal effect of 5% niclosamide ethanolamine granules in large-scale settings].

OBJECTIVE: To evaluate the field molluscicidal effect of 5% niclosamide ethanolamine granules, so as to provide a novel Oncomelania hupensis snail control approach for emergency treatment of high-risk settings. METHODS: Snail control tests with spraying of 5% niclosamide ethanolamine granules were conducted in two settings of 2 counties, and the dose-, time- and setting-specific field molluscicidal effects were tested. RESULTS: In the small-scale setting, spraying of 5% niclosamide ethanolamine granules at doses of 30, 40 and 50 g/m2 resulted in 54.55%, 68.41% and 73.45% 1-day snail mortality, 57.27%, 68.59% and 80.28% 3-day snail mortality, and 63.49%, 77.58% and 85.55% 7-day snail mortality, respectively, and no significant differences were detected in 1- and 3-day snail mortality caused by spraying of 5% niclosamide ethanolamine granules at doses of 30 and 40 g/m2 (all P > 0.05), while significant difference was found in the 7-day snail mortality (χ2 = 4.549, P < 0.05). In addition, spraying of 5% niclosamide ethanolamine granules at doses of 40 and 50 g/m2 resulted in comparable 1-, 3- and 7-day snail mortality (all P > 0.05). In the large-scale setting, spraying of 5% niclosamide ethanolamine granules at a dose of 40 g/m2 resulted in 85.29% and 87.70% 3-day snail mortality, 83.89% and 91.02% 7-day snail mortality, and 83.41% and 91.84% 15-day snail mortality in the environment-cleaning group and non-cleaning group, respectively. The overall snail mortality was 90.02% in the environment-cleaning group 3 to 15 days after spraying, which was significantly higher than that (84.28%) in the non-cleaning group (χ2 = 9.950, P < 0.05). After 15 days of spraying with 5% niclosamide ethanolamine granules at a dose of 40 g/m2, the densities of living snails reduced from 19.90 and 19.83 snails/0.1 m2 to 0.60 and 2.60 snails/0.1 m2 in the environment-cleaning group and non-cleaning group, with 96.98% and 86.89% reductions, respectively. CONCLUSION: The appropriate dose of 5% niclosamide ethanolamine granules is 40 g/m2 for snail control in the field, and environment cleaning of vegetation with a height of more than 50 cm may improve the molluscicidal efficacy.

[Surveillance and risk assessment system of schistosomiasis in Jiangsu Province. I. Distribution of surveillance site and effectiveness of the system].

OBJECTIVE: To establish the surveillance and risk assessment system of schistosomiasis in Jiangsu Province, so as to provide technical support for timely understanding of the risk of schistosomiasis transmission and implementation of targeted control measures. METHODS: The surveillance sites of schistosomiasis were assigned according to the epidemic status and endemic type of schistosomiasis as well as the characteristics of the water system, and the prevalence of Schistosoma japonicum in humans and domestic animals, and snail status were investigated. In addition, the quality control of serum detection of S. japonicum infections was performed. The prevalence of human and animal S. japonicum infections, snail status and missing diagnosis of serum detection were analyzed and compared among regions. RESULTS: A total of 27 surveillance sites of schistosomiasis were set up in 26 counties of 10 cities, Jiangsu Province, including 14 sites in transmission-interrupted villages and 13 sites in transmission-controlled villages, and 15 sites in marshland and lake regions, 9 sites in plain regions with water network and 3 sites in mountainous region. In the 27 surveillance sites, a total of 16 617 residents were screened for S. japonicum infection by using dipstick dye immunoassay (DDIA), and 326 were sero-positive, with a sero-prevalence of 1.96% (2.17% for men and 1.8% for women). Of the 326 individuals undergoing parasitological examination, 2 positive cases were detected in the marshland and lake region, with a S. japonicum human prevalence of 0.01%. Of the 762 floating population detected, 10 were positive for blood test, with a sero-prevalence of 1.31%, and no egg-positive individuals were detected. No infection was found in the 476 domestic animals. Of the 746 settings surveyed, a total of 240.7 hm2 snail area was detected, with a mean snail density of 0.06 snails/0.1 m2, and no infected snails were found. There were 780 quality-control sera detected in 26 surveillance sites of schistosomiasis, and the gross coincidence rate was 95.13%, with misdiagnosis rate of 1.28% and missing diagnosis rate of 19.23%. CONCLUSION: The surveillance sites of schistosomiasis show reasonable distribution in Jiangsu Province, and the endemic situation of schistosomiasis appears a low level in the whole province.

[Surveillance and forecast system of schistosomiasis in Jiangsu Province. VI. Detection technology of water infectivity based on enrichment of Schistosoma japonicum cercariae on water surface].

OBJECTIVE: To explore the enrichment technique of Schistosoma japonicum cercariae on the water surface, so as to establish a new method combined with the existing technology to detect the cercarial infested water body quickly and sensitively. METHODS: Soybean oil, gasoline, kerosene and isophorone were screened as expanding agents. The cercariae were enriched by the thrust of the expanding agents when diffusing on the water surface, and PE adsorption film and C-6 film were applied to seize them so as to determine the infectivity of the water quickly. The relationship between the dose of expanding agents and diffusion radius were explored. RESULTS: Gasoline, kerosene and isophorone were suitable expanding agents, and the diffusion effect of isophorone was the best. After the enrichment by the expanding agents, the detection rate of cercariae of the method seizing cercariae with the film significantly improved in the water. CONCLUSION: This new method could effectively improve the detection rate of the cercarial infested water and is suitable for the low-degree infested water.

[Surveillance and risk assessment system of schistosomiasis in Jiangsu Province. II. Surveillance pattern and effect of Oncomelania hupensis snail status in Dongtai City, Jiangsu Province].

OBJECTIVE: To explore the method of Oncomelania hupensis snail surveillance in transmission-interrupted regions of schistosomiasis, so as to provide a new pattern for the surveillance of snail status in the transmission-interrupted areas. METHODS: In Dongtai County, north of Jiangsu Province where the transmission of schistosomiasis was interrupted, the surveillance of snail status was performed by means of the village-level general survey, village-level sampling survey, snail survey in key settings of township and county, and snail reporting by residents. In addition, quality-control snail sites were set up for quality control. The effectiveness and cost of the four methods of snail surveillance was compared. RESULTS: A total of 163 079 settings and 22 785.62 hm2 were surveyed in Dongtai County from 2008 to 2013, and 89 residual snail breeding sites were found, with a snail area of 1.48 hm2. The patterns of village-level general survey, village-level sampling survey, and snail survey in key settings of township and county were employed for investigation of 94 550, 45 033 and 23 496 settings, consisting of 57.98%, 27.61% and 14.41% of total settings, and 2, 0 and 6 settings were found with snails, with 0.021/thousand, 0, and 0.255/thousand detection rates of settings with snail breading sites, respectively. The pattern of snail survey in key settings of township and county was more effective than that of village-level survey to detect-snail breeding sites (χ2 = 19.158, P = 0). The recovery rate of quality-control snail breeding sites was 52.56%, 38.27% and 73.62% for the three patterns of snail survey, respectively, and the pattern of snail survey in key settings of township and county showed a higher quality for snail survey than that of village-level survey (χ2 = 111.597 and 85.991, both P = 0). During the period from 2008 to 2013, 289 person-times reported 279 suspected snail habitats and 1 501 living snails, and no Oncomelania snails were found. During the 6-year period, there were 1617.5, 964.7 and 527.7 thousand RMB invested for village-level general survey, village-level sampling survey, and snail survey in key settings of township and county, and the cost of snail survey per hm2 was 129.88, 133.6 and 162.57 RMB/hm2, respectively. The cost of village-level general survey and snail survey in key settings of township and county to detect a snail-breeding site was 808 800 and 88 000 RMB, respectively (t = 12.850, P = 0.000), and the cost of snail survey in key settings of township and county was 10.88% of that of village-level general survey. CONCLUSION: The snail survey in key settings of township and county is a highly effective and high-quality method for snail surveillance, which miay serve as a prior way for the surveillance of snail status in the transmission-interrupted areas of schistosomiasis.

Schistosoma japonicum risk in Jiangsu province, People's Republic of China: identification of a spatio-temporal risk pattern along the Yangtze River.

The risk for Schistosoma japonicum infection in Jiangsu province, People's Republic of China, was investigated by a mouse bioassay. Various investigations were conducted in the period 2009-2011 with the presentation here representing the summary of the results from 45-50 sites in the marshlands along the Yangtze River's course through the province. Indices representing three aspects of the infection were collected to assess risk: (i) the proportion of sentinel points where at least one mouse infection was recorded; (ii) the proportion of infected mice at each of these sites; and (iii) the average worm burdens. Directional distribution analysis and scan statistics were used to explore the spatio-temporal risk pattern. The spatial distribution was oriented along the Yangtze River and the directional distributions for the proportion of infected mice and mean worm burdens were similar for the positive sentinel sites. Four statistically significant clusters were detected in 2009, but only one in 2010 and 2011, respectively. Temporal windows for infection risk were seen in June and September. The study illustrates the utility of spatio-temporal analysis in assessing the risk for schistosomiasis. This approach should be useful with respect to surveillance and response that can be expected to be increasingly applied when moving from morbidity control to transmission control.

[Field evaluation of a novel plant molluscicide "Luo-Wei" against Oncomelania hupensis I molluscicidal effect by the spraying method in lake and marshland regions].

OBJECTIVE: To evaluate the field effect of a novel plant molluscicide "Luo-wei" (Tea-seed distilled saponins, TDS) against Oncomelania hupensis in the lake and marshland regions. METHODS: A spraying experiment was carried out in the grassland of two schistosomiasis endemic counties, including Xingzi in Jiangxi Province and the Huarong in Hunan Province, to assess the molluscicidal effect of 4% TDS comparing with 50% wettable powder of niclosamide ethanolamine salt (WPN). The chi2 test was used to examine the differences between regions, molluscicides, or days after spraying. RESULTS: Following 1, 3, 7, and 15 days of test, the snail mortality showed a simultaneous increase both in TDS group (70.43%-86.88%) and WPN group (70.21%-85.35%). There is no significant difference between TDS and WPN of day 1, 7 and 15 (all P values > 0.05), but except for day 3 (chi2 = 3.910, P = 0.048). By the end of day 15, the snail mortality for TDS was 86.53% in Xingzi and 88.28% in Huarong, while for WPN was 83.04% in Xingzi and 93.69% in Huarong respectively; the decline rate of snail density for TDS was 85.29% in Xingzi and 93.53% in Huarong, while for WPN was 85.29% in Xingzi and 93.53% in Huarong respectively. The adjusted mortality of different days ranged from 69.63% to 86.54% in the the TDS group, and 69.41% to 86.54% in the WPN group. CONCLUSION: The molluscicidal effect of TDS by spraying is similar to that of WPN. It is time to popularize this new plant molluscicide (TDS) in a wider field.

Spatio-temporal analysis to identify determinants of Oncomelania hupensis infection with Schistosoma japonicum in Jiangsu province, China.

BACKGROUND: With the successful implementation of integrated measures for schistosomiasis japonica control, Jiangsu province has reached low-endemicity status. However, infected Oncomelania hupensis snails could still be found in certain locations along the Yangtze river until 2009, and there is concern that they might spread again, resulting in the possible re-emergence of infections among people and domestic animals alike. In order to establish a robust surveillance system that is able to detect the spread of infected snails at an early stage, sensitive and reliable methods to identify risk factors for the establishment of infected snails need to be developed. METHODS: A total of 107 villages reporting the persistent presence of infected snails were selected. Relevant data on the distribution of infected snails, and human and livestock infection status information for the years 2003 to 2008 were collected. Spatio-temporal pattern analysis including spatial autocorrelation, directional distribution and spatial error models were carried out to explore spatial correlations between infected snails and selected explanatory factors. RESULTS: The area where infected snails were found, as well as their density, decreased significantly between 2003 and 2008. Changes in human and livestock prevalences were less pronounced. Three statistically significant spatial autocorrelations for infected snails were identified. (i) The Moran's I of infected snails increased from 2004 to 2007, with the snail density increasing and the area with infected snails decreasing. (ii) The standard deviations of ellipses around infected snails were decreasing and the central points of the ellipses moved from West to East. (iii) The spatial error models indicated no significant correlation between the density of infected snails and selected risk factors. CONCLUSIONS: We conclude that the contribution of local infection sources including humans and livestock to the distribution of infected snails might be relatively small and that snail control may limit infected snails to increasingly small areas ecologically most suitable for transmission. We provide a method to identify these areas and risk factors for persistent infected snail presence through spatio-temporal analysis, and a suggested framework, which could assist in designing evidence based control strategies for schistosomiasis japonica elimination.

[Establishment and application of quality control system for detection of schistosomiasis in Jiangsu Province I ability of serological detection among county-level personnel].

OBJECTIVE: To evaluate the ability for serological screening of schistosomiasis among county-level personnel, so as to provide the evidence for establishing the quality control system of field detection of schistosomiasis. METHODS: The standard serum panel was prepared for the quality assessment of schistosomiasis diagnostic capability, and detected by county-level personnel in the endemic field simultaneously using single-blind method. The rates of coincidence, misdiagnosis and missed diagnosis were calculated compared with the standard results. RESULTS: Totally 780 samples of standard serum were detected in 26 counties, and showed 134 positive and 646 negative samples. The rates of coincidence, misdiagnosis and missed diagnosis were 95.13%, 1.28% and 19.23%, respectively, and there was a significant difference between the detection results and the standard results (chi2 = 11.6053, P = 0.0007). Among the 26 counties investigated, the misdiagnosis occurred in 5 counties (19.23%) and missed diagnosis occurred in 21 counties (80.77%). The misdiagnosis rate and missed diagnosis rate of serological screening of schistosomiasis were 0-2.08% and 16.67%-33.33% in beach, hilly, water net and marshland endemic areas, respectively, and no significant differences were found in the misdiagnosis rate and the missed diagnosis rate among various types of endemic areas (chi2 = 1.590 and 1.757, P = 0.6671 and 0.6244). The rates of misdiagnosis and the missed diagnosis were 1.14% and 1.39%, and 18.18% and 20.00% in the schistosomiasis transmission-controlled and the schistosomiasis transmission-interrupted areas, respectively, and no significant differences were found in the misdiagnosis rate and missed diagnosis rate between the schistosomiasis transmission-controlled and transmission-interrupted areas (chi2 = 0.008 and 0.001, P = 0.931 and 0.974). CONCLUSIONS: The missed diagnosis is a major cause for the reduction of quality of schistosomiasis detection at the county level in Jiangsu Province, and the coincidental detection of schistosomiasis with standard serum in the field is one of effective approaches for the control of the quality of schistosomiasis detection.

[Field evaluation of a novel plant molluscicide "Luo-wei" against the snail Oncomelania hupensis III molluscicidal effect by spraying method in hilly regions].

OBJECTIVE: To evaluate the molluscicidal effect of a novel plant molluscicide "Luo-wei" (Tea-seed distilled saponins, TDS) against Oncomelania httpensis in billy regions. METHODS: The molluscicidal effect of TDS at a dose of 5 g/m2 by the spraying method against Oncomelania snails was assessed in a setting with a high snail density in Husban Village, Jiangning District of Nanjing City, and the effect was compared with that of 50% wettable powder of niclosamide ethanolamine salt (WPN) at a dose of 2 gIm2 at different time after spraying. RESULTS: Afterl, 3, 7 and 15 day (days) of the spraying experiment, the snail death rates of the TDS group were 56.47%, 57.32%, 90.58% and 93.41% respectively, while those of the WPN group were 49.22%, 53.37%, 95.92% and 97.26%, respectively. The differences between the rates of the 2 groups 1, 7, 15 day (days) after the spraying were statistically significant (all P < 0.05). Fifteen days after the spraying, the density of living snails reduced from 20.30 +/- 16.20 snails/0.1 m2 and 23.67 +/- 21.22 snails/0.1 m2 to 2.28 +/- 2.17 snails/0.1 m2 and 1.27 +/- 0.76 snailsl0.1 m2 in the TDS group and WPN group, respectively, with the reduction rates of 88.77% and 94.63%, respectively. CONCLUSION: TDS can be used as an alternative molluscicide for the control of Oncornelania snails in hilly areas, which deserves further popularization.