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To set up a framework of indicators for schistosomiasis and malaria to guide the formulation and evaluation of vector-borne disease control policies focusing on adaptation to the negative impact of climate change.A 2-level indicator framework was set up on the basis of literature review, and Delphi method was applied to a total of 22 and 19 experts working on schistosomiasis and malaria, respectively. The result was analyzed to calculate the weight of various indicators.A total of 41 questionnaires was delivered, and 38 with valid response (92.7%). The system included 4 indicators at first level, i.e. surveillance, scientific research, disease control and intervention, and adaptation capacity building, with 25 indicators for schistosomiasis and 21 for malaria at the second level. Among indicators at the first level, disease surveillance ranked first with a weight of 0.32. Among the indicators at the second level, vector monitoring scored the highest in terms of both schistosomiasis and malaria.The indicators set up by Delphi method are practical,universal and effective ones using in the field, which is also useful to technically support the establishment of adaptation to climate change in the field of public health.

To evaluate the effect of comprehensive measures with an emphasis on schistosomiasis infection source control by replacing cattle with machine.In 2011, 2 villages from each of Jingzhou District, Jianli County and Jiangling County, Hubei Province, were selected as intervention group where the comprehensive measures were implemented, while 2 villages from Shishou City served as control with routine control activities. A cluster random sampling was carried out in the 8 villages with more than 300 people in each village were sampled. Stool examination using modified Kato-Katz was applied for identification of the infected persons and hatching test for cattle survey. The systemic sampling was applied for snail survey, fecal specimens from the field were examined by hatching test. Each sample was examined three times. Data were collected for the analysis of control effect between intervention and control groups in 2007 (baseline), 2009 (before implementation of comprehensive measures) and 2011 (post-intervention).In intervention villages, the overall prevalence in human reduced significantly from 3.6% (135/3 772) in 2007 and 2.0% (63/3 116) in 2009 to 0.9% (21/2 396) in 2011 (chi2 = 43.411, chi2 = 11.840, P0.05). Until 2011, there were no cattle in intervention group; the prevalence decreased by 52.6% in human and about 100% in cattle from 2010 to 2011. In control group, the infection rate in residents in 2007, 2009 and 2011 was 4.5% (64/1 410), 2.6% (34/1 294) and 1.8% (24/1,320), respectively (chi2 = 16.178, P0.05), and 5.1% (8/158) in 2007, 1.6% (3/187) in 2009 and 1.6% (3/189) in 2011 in cattle, respectively (chi2 = 3.387, P0.05). The infection rate in human and cattle fell by 25.0% and 5.9% from 2010 to 2011, respectively. There was a significant difference in human infection rate between the intervention and control groups after intervention (chi2 = 6.309, P0.05). No infected snails were detected in intervention and control groups. No positive feces from the field was found in the intervention group, 7.5% positive rate was recorded in the control.The comprehensive measures focused on infection source control by replacing cattle with machine can effectively control Schistosoma japonicum transmission, with a significant decrease of the prevalence in human and cattle.

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

To explore the relationship between schistosome serum test positive rate of residents and positive rate of Oncomelania snails in a national schistosomiasis surveillance site of Jiangling County.According to the national schistosomiasis monitoring scheme, the data of surveillance including the schistosome serum test positive rates of residents and positive rates of Oncomelania snails from 2005 to 2011 were collected and analyzed statistically.From 2005 to 2011, the schistosome serum test positive rates of residents were 26.09%, 11.84%, 10.37%, 10.09%, 12.08%,9.61%, and 6.00%, respectively; the schistosome positive rates of Oncomelania snails were 0.36%, 0.08%, 0.15%, 0.129%, 0.067%, 0.091%, and 0.045%, respectively. There was a significant positive correlation between them (r = 0.929, P0.01).There is a positive correlation between schistosome serum test positive rate of residents and positive rate of Oncomelania snails. Therefore, we should strengthen the snail control.

To establish an index system for rapid assessment of environment with high transmission risk of schistosomiasis in marshland and lake regions.The alternative indices were established preliminarily by the documentary method, and then the Delphi method was used two rounds to select the indices and establish the index system. The degree of familiar and authority of the experts as well as the weights of all indices were assessed.A total of 3 primary indices namely morbidity in domestic animals, morbidity in humans and Oncomelania snail status were established, among which the weight of morbidity in domestic animals (0.68) was the highest. Totally 16 secondary indices were established, among which the combinative weights of the positive rate of wild feces (0.09), the infection rate of livestock (0.09), the infection rate of humans (0.07), the number of cases with acute schistosomiasis (0.07), the area with infected snails (0.07), and the density of infected snails (0.07) were the highest. The coefficients of familiar degree and authority degree of the experts of the primary indices were 0.79-0.85 and 0.88-0.91, and those of the secondary indices were 0.68-0.86 and 0.77-0.91, respectively.The index system for rapid assessment of environment with high transmission risk of schistosomiasis in marshland and lake regions is established preliminarily. Using this system, we can assess the key endemic indices of humans, domestic animals and snails to understand the endemic situation in the investigated sites.

To establish a scientific, objective and operational assessing system for schistosomiasis endemicity, so as to provide a scientific evidence for revising the current Criteria for Control and Elimination of Schistosomiasis in China (GB 15976-2006).A questionnaire was designed based on reference review and 20 scientists working in the field of schistosomiasis control, research or management were investigated by using the Delphi method. The importance of each index reflecting the endemicity of schistosomiasis was scored by each scientist. The assessing system for endemicity of schistosomiasis was established and the normalized weight and combined weight were calculated.The assessing system included three indices in the first grade and seven indices in the second grade. Among the indices in the first grade, the normalized weights of infection status of human beings, infection status of livestock, and Oncomelania snail's status were 0.360 2, 0.335 2, and 0.304 6, respectively. Among the indices in the second grade, the prevalence of livestock showed the highest combined weight of 0.335 2 while the infection rate of snails showed the lowest score of 0.093 3.The indexes of the assessing system for the endemicity of schistosomiasis established are reasonable, comprehensive, and authoritative, which provide the scientific evidence for revising the currently available Criteria for Control and Elimination of Schistosomiasis in China.

To analyze the changing rules of schistosomiasis endemic situation in the area of transmission that has been interrupted before and after they reach the criteria of transmission interruption, so as to offer the basis of amending to the criteria of schistosomiasis transmission interruption and a more scientific, standardized assessment and evaluation of the effects of schistosomiasis control in the future.Nineteen counties of transmission that has been interrupted in 9 provinces nationwide were selected and investigated with the retrospective research method to collect and record the endemic detailed data 10 years before they reach the criteria of transmission interruption and several years later (ended in 2008 or 2009) and then a database was established. The changing rules of various disease indices in different endemic areas before and after reaching the criteria of transmission interruption were analyzed and compared.The average time from the transmission control to the transmission interruption was 17 years in the 17 counties. After reaching the criteria of transmission interruption, the infection rates of people turned down to a minimum level in various endemic areas, the infection rates in a few numbers of lake endemic areas and hilly endemic areas increased slightly after the transmission interruption 4-9 years later, but all of them were below 1%. The densities of living Oncomelania snails in lake endemic areas and water-network endemic areas were high and the changes were great each year, and the densities of living snails were much lower in hilly endemic areas than in the above two types of areas and they came to the lowest 4 years before and after the transmission interruption. The infected snails appeared occasionally in lake endemic areas, and they recurred 6 years and 10 years after the transmission interruption in water-network endemic areas and hilly endemic areas, respectively. The continued time without infected snails found before reaching transmission interruption was 2.71 +/- 1.10 years averagely in transmission-interrupted counties with endemic stable, and was 3. 80 +/- 1.43 years in lake endemic areas.It is possible to maintain a low level of population schistosome infection, and the endemic rebound is shown as snail rebound after the endemic areas reach the criteria of transmission interruption, The infected snails could be the comprehensive index reflecting the control achievement and the risk of schistosomiasis transmission. So the persistent control of infected snails is the fundament of schistosomiasis transmission interruption. It is suggested that in our current social and economic development and science and technology capacity conditions, the status of no infected snails found continuously for 5 years would be one of the criteria of schistosomiasis transmission interruption.

To analyze the changes of schistosomiasis endemic situation before and after reaching the criteria of schistosomiasis transmission control or transmission interruption in endemic rebounded areas, so as to offer the information for modifying the criteria of schistosomiasis control and elimination, and consolidating achievements of schistosomiasis control in People's Republic of China.Twelve counties with endemic rebound were selected from seven endemic provinces and investigated with the retrospective research method. The data including the epidemic information and relative materials 10 years before the counties reached the criteria of transmission control and several years later (until 2008 or 2009) were collected. The changes of epidemic situation of these counties before and after the transmission was under control or interrupted, and the factors causing the endemic rebound were analyzed.Counties consolidated the endemic situations with an average time of 5 +/- 3 years after the transmission control, with endemic rebound normally caused by single factor. The ratio of Oncomelania snail areas to historically accumulative snail areas increased over 10% in hilly endemic regions and lake endemic regions in 7 and 12 years separately, while it was stabilized in a low level in water-network endemic areas. The rebound peak time of infected snail densities was consistent with or later than that of densities of living snails. The prevalence of schistosome infection in humans in lake endemic regions rebounded 2 years after transmission under control. The transmission interruption counties consolidated the endemic situations with an average time of 7 +/- 4 years. The human prevalence of schistosome infection decreased to a very low level after the counties reaching the criteria of transmission interruption. The snail areas increased to over 2% of historically accumulative snail areas 3-6 years after transmission interruption in lake, water-network endemic areas successively, while densities of living snails and infected snails were increased at the same year or 2-3 years later.The endemic rebound in regions after the transmission under control or interrupted is caused by biological, natural and social factors and mainly presents as the rebound of snail status. The modification of criteria for schistosomiasis control and elimination should consider the influence of variation of snails, snail areas and density of infected snails on endemic situations in different endemic areas comprehensively. Sensitive and valid surveillance and forewarning system should be established to strengthen the monitoring and consolidating endemic situation in endemic areas after the transmission under control or interrupted.

To summarize and analyze the process of the changes of schistosomiasis infection and Oncomelania snails in schistosomiasis transmission-controlled areas to explore the rules of the impact of changes of snail indexes on human infection before and after the stage of transmission control, so as to provide the evidence for editing snail indexes in the schistosomiasis controlled criterion and a more scientific, standardized control assessment and evaluation.Twenty-one schistosomiasis transmission-controlled or transmission-interrupted counties in lake endemic areas and hilly endemic areas in 8 provinces were selected and investigated retrospectively to collect schistosomiasis epidemiological information 10 years before these counties reached the criterion of transmission control and the subsequent years until 2008 or 2009. A " Standard county schistosomiasis epidemic survey data review software" was developed to establish a national epidemic retrospectively database; the trends of changes of snail status, infected snail status and human infection status were analyzed in different years. The trends and rules of the changes of snail areas, emerging snail areas, living snail densities, infected snail densities, snail infection rates and human infection rates were analyzed and compared before and after the counties reached the schistosomiasis transmission-controlled criterion in different types of endemic areas.Before the transmission control, the human infection rate presented a declining trend in endemic areas. In lake endemic areas, the human infection rate declined to below 5% 4 years before the transmission control; in hilly endemic areas, the human infection rate declined to below 3% 8 years before the transmission control, and the human infection rates of the lake and hilly endemic areas declined to 2.10% and 1.45%, respectively, at the year of transmission control. However, 3 to 4 years after transmission control, the disease began to rebound, especially in lake endemic areas. The snail areas and snail densities declined year by year 10 years before the transmission control in the lake and hilly endemic areas, and the proportion of snail areas occupying the historic snail areas declined the lowest, being 2.75% and 0.55%, respectively, at the year of transmission control. The average densities of living snails kept a low level from 3-4 years before the transmission control to 9-10 years after the transmission control, and then rebounded. The new snail areas appeared 6-7 years after the transmission control and the snail areas and densities of living snails rebounded 9-12 years after the transmission control.The snail status can maintain a relatively low level during about 10 years after the transmission control in the lake and hilly schistosomiasis endemic areas, but the schistosomiasis status rebounded 5 years after the transmission control. While the comprehensive measures mainly including infectious source controlled are implemented, the snail surveillance and control should be still strengthened, and it is recommended that "the proportion of snail areas decreased" and "the control of infected snails" would be the indicators of the criterion of schistosomiasis transmission control.