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

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 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

Animals ; China ; epidemiology ; Female ; Humans ; Incidence ; Male ; Schistosoma japonicum ; Schistosomiasis japonica ; epidemiology ; transmission ; Urban Health

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

OBJECTIVETo study the dynamics of the reinfection of Schistosoma japonicum and related risk factors among the people in schistosomiasis endemic areas in China.

METHODSLiterature retrieval was conducted by using databases of PubMed, CNKI,VIP and Wanfang to collected all the data about the human re-infection of Schistosoma japonicum and related risk factors in the endemic areas in China. And a Mata-analysis was conducted on the literatures met the inclusion standards.

RESULTSEighteen studies involving 12 604 people for infection survey and 3 128 people for re-infection survey were included in the analysis. The overall infection rate was 20.8%, and the overall re-infection rate was 21.0% . The difference had no statistical significance (Z = 1.12, P = 0.26). The re-infection related factors included baseline infection intensity (OR = 3.58, 95% CI: 1.56-8.22); the index of contaminated water OR = 2.37, 95% CI: 1.08-5.22); distance from house to river-side (OR = 1.72, 95% CI: 0.41-7.30) and age (OR = 0.48, 95% CI: 0.19-1.23).

CONCLUSIONThe baseline infection intensity, the index of contaminated water and distance from house to river-side were the risk factors related to the re-infection of Schistosoma japonicum and age was a protective factor.

Animals ; Asian Continental Ancestry Group ; China ; Humans ; Risk Factors ; Schistosoma japonicum ; Schistosomiasis japonica ; epidemiology ; parasitology

China ; epidemiology ; Epidemiologic Methods ; Geographic Information Systems ; Hemorrhagic Fever with Renal Syndrome ; epidemiology ; Humans ; Malaria ; epidemiology ; Schistosomiasis japonica ; epidemiology

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 provide the fittest model for forecasting schistosomiasis prevalence in Haokou village of "breaking dikes or opening sluice for waterstore" in Dongting Lake areas by comparing the results of Moving Average, Exponential Smoothing, Autoregressive Model and Autoregressive integrated moving average model (ARIMA model) from 1990 to 2002.

METHODSError sum of square of four statistical methods was compared and the fittest model was chosen.

RESULTSError sum of square of predicted schistosomiasis prevalence rates in Haokou village from 1994 to 2002 were 39.40, 39.86, 26.63, 22.54 respectively.

CONCLUSIONARIMA model seemed to be the fittest one in the prediction of schistosomiasis prevalence in Haokou village of "breaking dikes or opening sluice for waterstore" in Dongting Lake from 1990 to 2002.

Animals ; China ; epidemiology ; Epidemiologic Methods ; Forecasting ; Humans ; Models, Statistical ; Prevalence ; Risk Assessment ; Schistosomiasis japonica ; epidemiology ; Time Factors

OBJECTIVETo assess the potential impact of warming climate in winter to the scale and severity of schistosomiasis epidemics in China.

METHODSBased on the data of mean temperature and monthly minimum temperature in January from 126 (out of 733) weather observation stations in China, the trend and oscillation amplitude was analyzed. The impact of warming climate in winter to the scale of schistosomiasis spreading was assessed, using the indices of 0 degrees C mean temperature and -4 degrees C mean monthly minimum temperature in January. Correlation between these two indices was analyzed.

RESULTSEvidences showed the warming climate in winter was seen all over China with the mean monthly minimum temperature and the mean temperature in January had increased 1.3 degrees C and 0.9 degrees C since 1986. The contours of mean monthly minimum temperature -4 degrees C and mean temperature 0 degrees C in January moved 1 - 2 latitudes northward.

CONCLUSIONThe warming climate phenomenon seen in winter was considered favorable to the living of snails in winter, resulting in the possible increase of northward spreading of snails.Thus, monitoring of snails should be paid special attention.

Animals ; China ; epidemiology ; Climate ; Disease Reservoirs ; Female ; Health Education ; Humans ; Male ; Prevalence ; Schistosoma japonicum ; physiology ; Schistosomiasis japonica ; epidemiology ; prevention & control ; Seasons ; Snails ; parasitology ; physiology ; Temperature