OBJECTIVETo study an intervention model of "schools without infected students with schistosoma japonica", to control and prevent students from schistosoma infection.

METHODSTwelve primary schools of four heavy endemic counties (districts) with schistosomiasis in the Poyang Lake areas were selected as the study fields, of which, ten schools were the experimental groups, and the other two schools were the control groups by cluster random sampling. All enrolment students were the target population. The baseline survey was carried out in 2005, and an intervention model, "information dissemination + behavior participation + behavior encouragement", was applied in the experiment groups in 2006 - 2008, then the effect of intervention was assessed.

RESULTSBefore intervention (2005), the anti-schistosomiasis knowledge awareness rate of experimental and control groups were 14.75% (324/2196) and 16.58% (91/549), and the different was not significant (χ(2) = 1.14, P > 0.05); the rate of accurate attitude of anti-schistosomiasis were 14.71% (323/2196) and 11.84% (65/549) in experimental and control groups, and the difference was not significant (χ(2) = 2.98, P > 0.05); the rate of contacting infected water were 15.44% (18 988/122 976) and 15.03% (4622/30 744) in experimental and control group and the difference was not significant (χ(2) = 3.13, P > 0.05); and the infection rate of schistosomiasis of experiment control groups were 9.65% (212/2196) and 10.56% (58/549), the difference was not significant (χ(2) = 0.41, P > 0.05). After one year intervention (2006), the anti-schistosomiasis knowledge awareness rate of experimental and control groups were 97.79% (2032/2078) and 18.11% (98/541), and the different was significant (χ(2) = 1794.31, P < 0.01); the rate of accurate attitude of anti-schistosomiasis were 99.09% (2059/2078) and 13.49% (73/541) in experimental and control group, and the difference was significant (χ(2) = 2077.45, P < 0.01). After 1 - 3 years intervention (2006 - 2008), there were no any contactors with infected water and infectors with schistosome in students of the experiment group in successive 3 years. While in the control group of the same period, the rate contacting infected water were 16.12% (4884/30 296), 11.11% (3079/27 720) and 12.25% (3451/28 168); the infection rate of schistosomiasis were 8.87% (48/541), 7.47% (37/495) and 7.95% (40/503), respectively.

CONCLUSIONThe intervention model of health promotion, "information dissemination + behavior participation + behavior encouragement", can effectively control and prevent students from infecting schistosoma japonica in heavy endemic areas with schistosomiasis.

Animals ; Health Promotion ; Humans ; Schistosomiasis ; prevention & control ; Schistosomiasis japonica ; School Health Services ; Schools ; Students

OBJECTIVE: To construct a schistosomiasis transmission risk assessment system in Wuhan City and preliminary evaluate its application effect, so as to promote the rational allocation of schistosomiasis control resources and accelerate the progress towards schistosomiasis elimination. METHODS: The schistosomiasis risk assessment indicators were collected through referring schistosomiasis surveillance data of Wuhan City from 2014 to 2020, literature review and expert interviews. Indicators within each criterion and sub-criterion were screened using the Delphi method, and a hierarchical structure model was created based on analytic hierarchy process. Quantitative assignment of each indicator was conducted according to relative importance, and the weight and combination weight of each criterion were calculated in each analytic hierarchy framework to create a schistosomiasis transmission risk assessment system, which was used for the schistosomiasis transmission risk assessment in 12 national schistosomiasis surveillance sites in Wuhan City. RESULTS: A three-level schistosomiasis transmission risk assessment system was preliminarily constructed, which included a target layer, 5 criterion layers and 21 sub-criterion layers. Of all indicators in the criterion layer, transmission route had the highest weight (0.433), followed by source of Schistosoma japonicum infection (0.294); and among all indicators in the sub-criterion layer, S. japonicum infection in Oncomelania hupensis and sentinel mice had the highest combination weight (0.125), followed by prevalence of S. japonicum infection in humans (0.091) and bovines (0.053), snail control by chemical treatment (0.049), positive rate of inquiry examinations (0.048), allocation of schistosomiasis control professionals (0.045), and areas of submerged snail-infested settings (0.041). Of the 12 national schistosomiasis surveillance sites in Wuhan City, there were 5 sites with weights of > 0.8, 4 sites with weights of 0.6 to 0.8, and 3 sites with weights of < 0.6 in 2020. CONCLUSIONS A schistosomiasis transmission risk assessment system has been constructed based on analytic hierarchy process in Wuhan City, which may provide a evidence-based basis for health resource allocation and decision-making for schistosomiasis control.
Animals ; Humans ; Cattle ; Mice ; Analytic Hierarchy Process ; Schistosomiasis/prevention & control* ; Schistosomiasis japonica/epidemiology* ; Snails ; Risk Assessment

OBJECTIVETo evaluate the practical value and the advantages of globe geographical positioning with wireless communication monitoring and supervision system in the field survey.

METHODSSpots which were randomly sampled by the National Ministry of Health for the investigation were chosen in the endemic areas for schistosomiasis in Jiangsu, Jiangxi, Anhui, Hunan, Hubei, Sichuan and Yunnan provinces. Portable GPS CEC9680 was used for collecting relevant waypoints and track, recording on-the-spot geographical positions. The positioning data package was sent back synchronously in the form of short message of SMS to the monitoring service center, and the moving routes of the terminal receiver monitored were displayed on the GIS map to achieve real-time supervision and staff scheduling.

RESULTSWith globe geographical positioning with wireless communication monitoring and supervision system, accurate positioning of 12 spots in the provinces of Jiangsu and 3 trial spots for schistosomiasis control with comprehensive treatment designated by the State Council has been established with real-time communicating recording, and monitoring systems.

CONCLUSIONThe globe geographical positioning with wireless communication monitoring and supervision system has provided a technical platform for the survey of schistosomiasis and other infectious diseases.

Animals ; China ; Environmental Monitoring ; methods ; Epidemiological Monitoring ; Geographic Information Systems ; Humans ; Schistosomiasis ; epidemiology ; prevention & control ; Schistosomiasis japonica ; prevention & control

OBJECTIVE: To evaluate the diagnostic efficacy of indirect haemagglutination assay (IHA) for detection of Schistosoma japonicum infections among boatmen and fishermen in Dongting Lake region, so as to provide insights into improving the schistosomiasis surveillance program among boatmen and fishermen. METHODS: The boatmen and fishermen were detected for S. japonicum infections using IHA and Kato-Katz technique or miracidium hatching test nylon gauze simultaneously at schistosomiasis testing sites in the anchor sites for boatmen and fishermen in the Dongting Lake region during the period from 2014 to 2016, and using IHA for serological screening followed by parasitological testing of seropositives during the period from 2017 to 2019. The sensitivity and specificity of IHA were evaluated for detection of S. japonicum infections among boatmen and fishermen, with the 2014-2016 parasitological testing results as a gold standard. In addition, the seroprevalence of S. japonicum infections was compared among boatmen and fishermen with different characteristics and among years. RESULTS: A total of 306 schistosomiasis testing sites were assigned for boatmen and fishermen, and a total of 143 360 person-time boatmen and fishermen were tested for S. japonicum infections in the Dongting Lake region from 2014 to 2019. The sensitivity and specificity of IHA were 69.9%, 97.3% and 96.1% (χ² = 74.6, P < 0.05), and 70.9%, 74.5% and 71.9% for detection of S. japonicum infections from 2014 to 2016 (χ² = 29.4, P < 0.05), respectively. The seroprevalence of S. japonicum infections reduced from 30.3% in 2014 to 1.8% in 2019 among boatmen and fishermen, appearing an overall tendency towards a decline (Z = 1 552.4, P < 0.05). In addition, male, individuals at ages of 45 to 60 years, full-time boatmen and fishermen were more likely to be seropositive for S. japonicum infections (all P values < 0.05). CONCLUSIONS The seroprevalence of S. japonicum infections appeared a tendency towards a decline among boatmen and fishermen in the Dongting Lake region year by year from 2014 to 2019. IHA presented a high efficacy for screening of S. japonicum infections among boatmen and fishermen in the Dongting Lake region.
Animals ; China/epidemiology* ; Hemagglutination ; Humans ; Lakes ; Male ; Middle Aged ; Prevalence ; Schistosoma japonicum ; Schistosomiasis/epidemiology* ; Schistosomiasis japonica/prevention & control* ; Seroepidemiologic Studies

OBJECTIVETo explore the spatial distribution and elimination of Oncomelania hupensis in mountainous regions.

METHODSPuge County in Tezi township was selected as the study site and the quadratus were placed randomly to investigate snail. The two sods with water were selected as the sites of snail elimination. One sod with area of 1000 m2 and mean density of 9.88 snails/0.11 m2 was selected as the trial group with 'heaping' method, and the other with area of 1000 m2 and mean density of 9.80 snails/0.11 m2 as the control group with sprinkling method. The molluscacidal effect of the two methods was compared by systematic sampling (5 m x 5 m). The sample size was 40 quadratus.

RESULTSThe snail distributed mainly in the sods with water, canals and farmlands. Among the three snail habitats, the area with snail was the most in the farmlands with relatively lower density of living snail; the next was the sods with water, with relatively higher density of living snail. Before killing snails, the rate of quadratus with snails was 87.50% in the trial site, and 82.50% in the control site. The mortality of snails was 3.89% in the trial site, and 4.16% in the control site. After three months, no living snails were found in the trial site, while in the control site, the rate of quadratus with snails (chi2 = 0.31, P > 0.05) and the mortality of snails (chi2 = 3.12, P > 0.05) did not decrease significantly, and the density of living snails only reduced by 8.88%.

CONCLUSIONThe 'heaping' method is an efficacious measure for snail control.

Animals ; China ; Environment ; Molluscacides ; Pest Control ; Schistosoma japonicum ; Schistosomiasis japonica ; prevention & control ; Snails ; parasitology

OBJECTIVETo understand the risk factors of schistosomiasis transmission in the Three Gorges Reservoir Area (TGRA) and to provide evidence for the development of control strategy.

METHODSApproaches including epidemiology, immunology and field survey were applied to investigate the potential risk factors which would involve the importation of infectious resources live mobile and migrant population, and livestock in the reservoir area. Meanwhile, observation on survival and reproductive status of snail under simulation habitats was also carried out, using ecological methods on snails. Strategy in preventing the spread of snail as infectious resources was also provided.

RESULTS175 mobile people from schistosomaisis endemic area of were tested and one person showed immunology tests positive with indirect hemagglutination test (IHA) and circumoral precipitin test (COPT), with a positive rate of 0.57%. Through the two-year period under observation, data showed that the snails with ribbon/smooth shells could survive and reproduce under habitats of simulation.

CONCLUSIONSOnce the infectious resource of schistosomiasis was introduced into the TGRA, the area became a new schistosomiasis epidemic area in TGRA which called for countermeasures to be taken.

Animals ; China ; epidemiology ; Disease Reservoirs ; Humans ; Risk Factors ; Schistosomiasis japonica ; epidemiology ; prevention & control ; transmission ; Snails ; parasitology

OBJECTIVETo obtain peptide mimicking epitopes of Schistosoma japonicum (S. japonicum) through screening of a phage peptide library and to test their potential for induction of protection.

METHODSS. japonicum infected sera from Microtus fortis (IMFS) and normal sera from Microtus fortis (NMFS) were used respectively to screen a 12-mers random peptide library by testing the reactivity of anti-S. japonicum serum with the phagotopes. After three rounds of biopanning, the pooled phages were used to immunize mice, after which challenge infection was performed.

RESULTSOf 12 randomly picked clones, 10 clones selected using IMFS and 7 clones selected using NMFS were shown to be antigenic. Significant reduction in adult worms (22.6%) and a high reduction (68.9%) in liver eggs were achieved following immunization with phages screened with IMFS. However, no protection was elicited by those selected with NMFS.

CONCLUSIONThe results show that the phagotopes are both antigenic and immunogenic, suggesting a potential use of phage displayed peptide as novel vaccines against S. japonicum.

Animals ; Arvicolinae ; parasitology ; Epitopes ; Helminth Proteins ; immunology ; Peptide Library ; Schistosoma japonicum ; immunology ; Schistosomiasis japonica ; prevention & control ; Vaccines ; immunology

OBJECTIVETo analyze the change of tendency on schistosomiasis epidemics in China in the last 5 years.

METHODSData on schistosomiasis epidemics in the history and particularly in the last 5 years were collected. Tendency and the re-emerging status after 1998 were analyzed.

RESULTSData in 2003 showed that in 42%, 40% and 53% of the provinces, counties and townships with epidemics, the transmission of the disease has been interrupted or controlled. The number of estimated patients of schistosomiasis and areas with snails were also reduced by 92.74% and 73.56%, in 2003. The annual estimated number of chronic cases was around 800 000 and 31 321.5 hectare of snail infested areas were newly identified in recent 5 years. Among 20 national villages under longitudinal surveillance, 30%, 70% and 35% of the villages were presented a tendency of increase in the rates of human infection, bovine infection and Oncomelania snails infection, respectively. A total of 38 counties from 7 provinces have re-emerged in schistosomiasis transmission after those counties having reached criteria of transmission under control or interrupted. In 6 non-endemic counties, snails were presented, and 16 marshlands in Xan river were found with appearance of acute cases of schistosomiasis. More snail infested areas were found in Shanghai, Zhejiang, and Fujian. Both snail infested areas and newly infected cases were occurred in urban areas along the Yangtze River.

CONCLUSIONThe tendency of increase was presented in focal areas along the Yangtze River, due to changes of environmental, ecological, societal and economic status, as well as on the forces of control.

Animals ; China ; epidemiology ; Disease Reservoirs ; Humans ; Praziquantel ; therapeutic use ; Prevalence ; Schistosomiasis japonica ; drug therapy ; epidemiology ; prevention & control ; Snails ; parasitology

OBJECTIVETo explore factors related to current prevention and treatment of Advanced cases on schistosomiasis.

METHODSIn-depth interviews were introduced to the qualitative study on 61 Advenced cases of schistosomiasis in Dongting Lake regions. Sampling was accidentally and judgmentally performed.

RESULTSRelated factors on prevention and treatment of Advenced cases of schistosomiasis would include: higher degree of social support for patients (61/61), excessive dependence on the past pattern of schistosomiasis control, lack of the idea that one should be responsible for his/her own health, lack of knowledge about prevention and treatment of schistosomiasis (28/61), older age (57.40 +/- 10.80), lower education (4.70 years), less family income, lack of effective medical insurance system and efficient close-to-client system.

CONCLUSIONActive participation from patients, medical institutions and society was needed to control Late Stage Schistosomiasis. Health education campaign should be intensified to improve the health awareness for schistosomiasis among residents in the heavy endemic areas. Medical insurance system should be set up in epidemic areas, while public health and cure systems for important diseases should be intensified in rural areas. The ability of public health system to be responsive and the accessibility of residents to health service system should be improved in rural areas as well.

Adult ; Aged ; Attitude to Health ; China ; epidemiology ; Female ; Humans ; Male ; Middle Aged ; Rural Health ; Schistosomiasis japonica ; epidemiology ; prevention & control ; therapy ; Socioeconomic Factors ; Surveys and Questionnaires

OBJECTIVETo use a mathematical model and computer simulation to study transmission dynamics and control of schistosomiasis in mountainous regions of Sichuan.

METHODSBased on studies of schistosomiasis japonica transmission in 20 villages in mountainous regions of Sichuan, a mathematical model was developed to characterize the impact of local environmental factors on transmission intensity. The model integrated site-specific factors and was calibrated to field epidemiological data from 3 subset villages. The dichotomic method was then used to predict different control measures.

RESULTSThe study showed high variations in prevalence of infection and infection intensity across villages, ranging between 3%-73%, 0.1-100 epg (eggs per gram stool), respectively. Important factors including occupation of local residents, exposure to contaminated water, microclimatic characteristics were integrated in the model. The predictions of dichotomic models showed that continuing chemotherapy (coverage between 50%-60%) could reduce infection intensities to 30%-80%, but could not change local transmission potential; therefore, the termination of chemotherapy would be followed by bouncing back of transmission. Sustaining targeted environmental interventions through snail and parasite oval control at certain coverage (30%-50%, respectively) could reduce the transmission to relatively stable levels. The model predictions showed that an integrated control (e.g., including both chemotherapy and environmental interventions) could suppress the transmission to an undetectable level even interruption of transmission between 5-10 years.

CONCLUSIONThe study demonstrated the feasibility of using a dynamic model, calibrated to local data, to gain insights into complicated processes underlying the transmission and informing site-specific control strategies.

Adolescent ; Adult ; Animals ; Child ; Child, Preschool ; China ; Environment ; Humans ; Middle Aged ; Models, Theoretical ; Schistosoma japonicum ; Schistosomiasis japonica ; epidemiology ; prevention & control ; transmission ; Snails ; parasitology