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In this study, the effects of ultrasonic and steam-cooking treatments on the physicochemical and emulsifying properties of bamboo shoots protein (BSP) were investigated. The particle size and the polydispersity index (PDI) of U-BSP (ultrasonic-BSP) both decreased. Fourier transform infrared spectroscopy (FTIR) showed that the secondary structure of U-BSP was more loose. Furthermore, X-ray diffraction (XRD) and thermogravimetric (TGA) analysis suggested that crystallinity amd thermal stability of U-BSP both deceased. The water and oil holding capacity (WHC/OHC) of U-BSP increased, while steam-cooking treatment had the reverse effect. We also investigated the effects of ultrasonic and steam-cooking treatments on BSP-stabilized emulsions. The viscosity of emulsion stabilized by U-BSP increased and the distribution of emulsion droplets was more uniform and smaller. The results showed that ultrasonic treatment significantly improved the stability of BSP-stabilized emulsions, while steam-cooking treatment had a significant negative impact on the stability of BSP-stabilized emulsions. The work indicated ultrasonication is an effective treatment to improve the emulsifying properties of BSP.
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This paper is in honour of Professor Marcel Tanner, President of the Swiss Academies of Arts and Sciences, and former Director of the Swiss Tropical and Public Health Institute (Swiss TPH), in Basel, Switzerland. In the 30 plus years since his first visit to China in 1989, Professor Tanner has tirelessly promoted research collaboration between Switzerland and China on health and tropical diseases through international meetings, scholar exchange, and training of young scientists. As a contribution to Professor Tanner's life's work of collaboration with Chinese scientists, we summarize here ideas conceived, work initiated and major outcomes. His approach, embodied in his flowery expression: "Alps and Himalayas never meet, but Swiss and Chinese can", marked the occasion in 2013 when Xinhua Co., Ltd., a pharmaceutical company in Shandong of China, agreed to produce tribendimidine, a new remedy for tropical helminth infections, that was the fruit of long-term research by scientists at the Swiss TPH in Basel, and National Institute of Parasitic Diseases (NIPD) in Shanghai. This was neither the first nor the last of Professor Tanner's forceful, yet diplomatic influence, and we follow in his footprints when continuing in Swiss-Chinese cooperation in tropical medicine.
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Schistosoma japonicum , Esquistosomiasis Japónica , Esquistosomiasis , Animales , China/epidemiología , Humanos , Esquistosomiasis/epidemiología , Esquistosomiasis/prevención & control , Esquistosomiasis Japónica/epidemiología , Esquistosomiasis Japónica/prevención & control , Organización Mundial de la SaludRESUMEN
BACKGROUND: Reliable and field-applicable diagnosis of schistosome infections in non-human animals is important for surveillance, control, and verification of interruption of human schistosomiasis transmission. This study aimed to summarize uses of available diagnostic techniques through a systematic review and meta-analysis. METHODOLOGY AND PRINCIPAL FINDINGS: We systematically searched the literature and reports comparing two or more diagnostic tests in non-human animals for schistosome infection. Out of 4,909 articles and reports screened, 19 met our inclusion criteria, four of which were considered in the meta-analysis. A total of 14 techniques (parasitologic, immunologic, and molecular) and nine types of non-human animals were involved in the studies. Notably, four studies compared parasitologic tests (miracidium hatching test (MHT), Kato-Katz (KK), the Danish Bilharziasis Laboratory technique (DBL), and formalin-ethyl acetate sedimentation-digestion (FEA-SD)) with quantitative polymerase chain reaction (qPCR), and sensitivity estimates (using qPCR as the reference) were extracted and included in the meta-analyses, showing significant heterogeneity across studies and animal hosts. The pooled estimate of sensitivity was 0.21 (95% confidence interval (CI): 0.03-0.48) with FEA-SD showing highest sensitivity (0.89, 95% CI: 0.65-1.00). CONCLUSIONS/SIGNIFICANCE: Our findings suggest that the parasitologic technique FEA-SD and the molecular technique qPCR are the most promising techniques for schistosome diagnosis in non-human animal hosts. Future studies are needed for validation and standardization of the techniques for real-world field applications.
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Schistosoma , Esquistosomiasis , Animales , Heces , Prevalencia , Estándares de Referencia , Esquistosomiasis/diagnóstico , Sensibilidad y EspecificidadRESUMEN
Being a zoonotic parasitic disease, schistosomiasis was widely spread in 12 provinces of Southern China in the 1950s, severly harming human health and hindering economic development. The National Institute of Parasitic Diseases at the Chinese Center for Diseases Control and Prevention, and Chinese Center for Tropical Diseases Research (NIPD-CTDR), as the only professional institution focussing on parasitic diseases at the national level, has played an important role in schistosomiasis control in the country. In this article, we look back at the changes of schistosomiasis endemicity and the contribution of NIPD-CTDR to the national schistosomiasis control programme. We review NIPD-CTDR's activities, including field investigations, design of control strategies and measures, development of diagnostics and drugs, surveillance-response of endemic situation, and monitoring & evaluation of the programme. The NIPD-CTDR has mastered the transmission status of schistosomiasis, mapped the snail distribution, and explored strategies and measures suitable for different types of endemic areas in China. With a good understanding of the life cycle of Schistosoma japonicum and transmission patterns of the disease, advanced research carried out in the NIPD-CTDR based on genomics and modern technology has made it possible to explore highly efficient and soft therapeutic drugs and molluscicides, making it possible to develop new diagnostic tools and produce vaccine candidates. In the field, epidemiological studies, updated strategies and targeted intervention measures developed by scientists from the NIPD-CTDR have contributed significantly to the national schistosomiasis control programme. This all adds up to a strong foundation for eliminating schistosomiasis in China in the near future, and recommendations have been put forward how to reach this goal.
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Academias e Institutos , Enfermedades Endémicas/prevención & control , Programas de Gobierno , Programas Nacionales de Salud , Esquistosomiasis Japónica , Animales , Bovinos , China/epidemiología , Erradicación de la Enfermedad , Desarrollo de Medicamentos , Humanos , Moluscocidas , Esquistosomiasis Japónica/tratamiento farmacológico , Esquistosomiasis Japónica/epidemiología , Esquistosomiasis Japónica/transmisión , VacunaciónRESUMEN
BACKGROUND: The use of pesticides during tea plant cultivation helps agricultural production and prevents and controls pests, diseases and weeds. It is of the utmost importance to balance pesticide application with tea quality, safety and consumer health. The uptake of pesticides into plants may lead to the presence of residues that are hazardous to human health, especially for some foliar-applied insecticides. The movability or penetration behavior of a pesticide remains unknown after it has been sprayed on a tea leaf. RESULTS: Two organophosphate (acephate, trichlorfon) and three neonicotinoid pesticides (imidacloprid, thiamethoxam and acetamiprid) were confirmed with respect to their removal from the treated fresh leaves of tea saplings via washing in a phytotron. Four of the targets have little penetrative ability into tea leaves, mainly existing (> 92%) on the tea leaf surface, except for trichlorfon (> 70%), for 30 days. With higher vapor pressures, trichlorfon and acetamiprid had relatively higher penetration ratios of 8.63-29.60% and 0.28-8.03% respectively. Two organophosphate insecticides were found to degrade more quickly, with lower final amounts of residues on and in the whole leaf compared to the neonicotinoid pesticides. In a field test, these residues could be reduced by 45-72% after a pre-harvest interval of 3 days, and by 16-89% after 7 days, when the fresh tea shoots were sprayed with 2 or 4 L m-2 water. CONCLUSION: Pesticides with different structures have different penetration abilities on the tea leaf surface, and some pesticides in commercial tea can be reduced by spraying with water before fresh leaves are picked. © 2020 Society of Chemical Industry.
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Riego Agrícola/métodos , Insecticidas/análisis , Residuos de Plaguicidas/análisis , Hojas de la Planta/química , Camellia sinensis/química , Contaminación de Alimentos/análisis , Neonicotinoides/análisis , Nitrocompuestos/análisis , Té/química , Tiametoxam/análisis , Agua/análisisRESUMEN
World Bank Loan Project (WBLP) for schistosomiasis control conducted from 1992 to 2001, resulted in significant reduction of schistosomiasis morbidity and mortality in People's Republic of China (P.R. China), with implementation of morbidity control. Thereafter, an integrated control strategy, which targeted blocking disease transmission from reservoir hosts to the environment, was initiated in order to conquer schistosomiasis rebound after WBLP completion. Data obtained from the national schistosomiasis control reporting systems was collected and analyzed. The number of confirmed cases and infected cattle decreased significantly from 2002 to 2017, while no infected snails were found by dissection for four consecutive years. However, lake and marshland regions and some parts areas of Yunnan Province require attention for rigorous schistosomiasis control efforts. There is need to strengthen precise interventions and sensitive surveillance to achieve schistosomiasis elimination in P.R. China.
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Bovinos/parasitología , Control de Enfermedades Transmisibles/estadística & datos numéricos , Morbilidad , Vigilancia de la Población , Esquistosomiasis/mortalidad , Esquistosomiasis/prevención & control , Animales , China/epidemiología , Humanos , Esquistosomiasis/epidemiologíaRESUMEN
BACKGROUND: In the roadmap on the neglected tropical diseases (NTD) the World Health Organization (WHO) aims at attaining at least 75% coverage of preventive chemotherapy in pre-school and school-age children by 2020. A randomized controlled trial was used to compare the effectiveness of praziquantel in treating Schistosoma haematobium in Africa using two different sources for the drug, Merck Limited Partnership (KgaA), Germany and Nanjing Pharmaceutical Factory (NPF), China. METHODS: More than 6,000 participants testing positive for S. haematobium infection were enrolled from three villages (shehias) situated in the northern, middle and southern part of Pemba Island, Zanzibar. Applying criteria of inclusion and exclusion, resulted in a study population of 152 people (84 males, 68 females). A randomized controlled trial was conducted assigning participants to either praziquantel from NPF or Merck KGaA. After one month, the cure rate of S. haematobium and adverse events were compared to evaluate effectiveness. The ratio of male to female, the ratio of light/high infection intensity, and the average value of age were calculated between the two drug manufacturers. Chi-squared test and T-test were used for consistency analysis. RESULTS: Out of the total of 73 cases receiving praziquantel from NPF, the cure rate achieved was 97.3% (73/75), while the 74 cases receiving the drug from Merck KgaA reached a similar cure rate (96.1% or 74/77). There was no significant difference between the two outcomes (χ2 = 0.003, P = 0.956). Among the 75 patients treat, only one (a 16-years old female student), who had received the drug made in China had slight adverse reactions manifested as dizziness, headache and abdominal pain. CONCLUSION: The efficacy of China-made praziquantel does not differ significantly from praziquantel made by Merck KGaA in Germany. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03133832.
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Antihelmínticos/normas , Antihelmínticos/uso terapéutico , Praziquantel/normas , Praziquantel/uso terapéutico , Schistosoma haematobium/efectos de los fármacos , Esquistosomiasis Urinaria/tratamiento farmacológico , Adolescente , Adulto , Anciano , Animales , Quimioprevención , Niño , Preescolar , China , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recuento de Huevos de Parásitos , Esquistosomiasis Urinaria/orina , Tanzanía , Resultado del Tratamiento , Adulto JovenRESUMEN
Despite significant progress, China faces the challenge of re-emerging schistosomiasis transmission in currently controlled areas due, in part, to the presence of a range of animal reservoirs, notably water buffalo and cattle, which can harbor Schistosoma japonicum infections. Environmental, ecological and social-demographic changes in China, shown to affect the distribution of oncomelanid snails, can also impact future schistosomiasis transmission. In light of their importance in the S. japonicum, lifecycle, vaccination has been proposed as a means to reduce the excretion of egg from cattle and buffalo, thereby interrupting transmission from these reservoir hosts to snails. A DNA-based vaccine (SjCTPI) our team developed showed encouraging efficacy against S. japonicum in Chinese water buffaloes. Here we report the results of a double-blind cluster randomized trial aimed at determining the impact of a combination of the SjCTPI bovine vaccine (given as a prime-boost regimen), human mass chemotherapy and snail control on the transmission of S. japonicum in 12 selected administrative villages around the Dongting Lake in Hunan province. The trial confirmed human praziquantel treatment is an effective intervention at the population level. Further, mollusciciding had an indirect ~50% efficacy in reducing human infection rates. Serology showed that the SjCTPI vaccine produced an effective antibody response in vaccinated bovines, resulting in a negative correlation with bovine egg counts observed at all post-vaccination time points. Despite these encouraging outcomes, the effect of the vaccine in preventing human infection was inconclusive. This was likely due to activities undertaken by the China National Schistosomiasis Control Program, notably the treatment, sacrifice or removal of bovines from trial villages, over which we had no control; as a result, the trial design was compromised, reducing power and contaminating outcome measures. This highlights the difficulties in undertaking field trials of this nature and magnitude, particularly over a long period, and emphasizes the importance of mathematical modeling in predicting the potential impact of control intervention measures. A transmission blocking vaccine targeting bovines for the prevention of S. japonicum with the required protective efficacy would be invaluable in tandem with other preventive intervention measures if the goal of eliminating schistosomiasis from China is to become a reality.
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Antihelmínticos/uso terapéutico , Enfermedades de los Bovinos/prevención & control , Praziquantel/uso terapéutico , Esquistosomiasis Japónica/prevención & control , Vacunación/veterinaria , Vacunas/uso terapéutico , Adolescente , Adulto , Anciano , Animales , Búfalos , Bovinos , Niño , Preescolar , China , Método Doble Ciego , Humanos , Persona de Mediana Edad , Esquistosomiasis Japónica/transmisión , Esquistosomiasis Japónica/veterinaria , Caracoles , Adulto JovenRESUMEN
An efficient method for the rapid extraction and clean-up of 20 pesticide residues from polyphenol-rich agricultural samples (tea, apple, broccoli, and shallot) for analysis by UPLC-MS/MS was developed. Following extraction, PVPP was used to precipitate polyphenols, supernatant was diluted to minimize matrix effects. Homogenized samples were vortexed in acetonitrile prior to cleanup with a combination of PVPP (150â¯mg), PSA (50â¯mg) and GCB (10â¯mg). Supernatant (1â¯mL) was filtered and diluted 10-fold before analysis. In 4 agricultural products that usually produce high interference, the matrix effects were overcome for all pesticides expect in green and oolong tea for acephate, omethoate, dinotefuran and nitenpyram. Mean recoveries ranged from 73% to 106%, and RSDâ¯â¦â¯13%. Limits of quantification ranged from 0.01 to 0.02â¯mgâ¯kg-1. PVPP as one of excellent QuEChERS material combined with dilution was verified as a promising method for multiple pesticide residues analysis in complex matrices.
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Agricultura , Fraccionamiento Químico/métodos , Costos y Análisis de Costo , Residuos de Plaguicidas/análisis , Residuos de Plaguicidas/aislamiento & purificación , Polifenoles/análisis , Seguridad , Cromatografía Líquida de Alta Presión , Contaminación de Alimentos/análisis , Espectrometría de Masas en Tándem , Factores de TiempoAsunto(s)
Enfermedades Transmisibles Importadas/epidemiología , Viaje , China/epidemiología , Enfermedades Transmisibles Importadas/parasitología , Humanos , Tanzanía/epidemiología , Trypanosoma brucei gambiense/aislamiento & purificación , Tripanosomiasis Africana/diagnóstico , Tripanosomiasis Africana/tratamiento farmacológico , Tripanosomiasis Africana/epidemiología , Tripanosomiasis Africana/parasitologíaRESUMEN
Schistosomiasis remains an important public health issue, with a large number of cases reported across sub-Saharan Africa, and parts of Asia and Latin America. China was once highly endemic, but has made substantial progress and is moving towards elimination of schistosomiasis. Meanwhile, despite long-term, repeated, school-based chemotherapy in many African countries, more than 90% of all schistosomiasis cases are concentrated in Africa, and hence, this continent constitutes the key challenge for schistosomiasis control. Opportunities and issues for international collaboration in the fight against schistosomiasis are outlined with a focus on China's experiences, including the role of public health authorities and intersectoral collaboration, use of new and effective snail control approaches and diagnostic tools adapted to the specific stage of control, as well as the strengthening of risk mapping and surveillance-response mechanisms. Training courses targeting African governmental officials and professionals, coupled with field visits of African scientists and control programme managers to China, and vice versa, are considered important for improved schistosomiasis control and elimination. The crucial question remains whether the Chinese experience can be translated and applied in African countries to improve the effectiveness of health interventions and scale-up.
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Internacionalidad , Esquistosomiasis/prevención & control , África/epidemiología , Animales , China/epidemiología , Control de Enfermedades Transmisibles/métodos , Erradicación de la Enfermedad , Salud Global , Humanos , Moluscocidas/farmacología , Vigilancia de la Población , Esquistosomiasis/epidemiología , Esquistosomicidas/uso terapéutico , Caracoles/efectos de los fármacosRESUMEN
OBJECTIVE: To study the morphological change of Schistosoma japonicum eggs processed by calcium cyanamide synthetic drug, so as to provide the basis for further study of the mechanism that calcium cyanamide synthetic drug to schistosome eggs. METHODS: The calcium cyanamide synthetic drug was added to the cattle feces containing schistosome eggs and mixed up, and then the cattle feces was stacked as original shape on the marshland. Blank controls were set at the same time. The cattle feces samples were collected and.the schistosome eggs were observed under a microscope on the 1st, 2nd, 3rd, 7th day after the experiment. RESULTS: By the effect of calcium cyanamide synthetic drug, the color of eggs was deepening gradually, the miracidia were atrophied, and the shells of eggs were thickened. The embryonic membrane of miracidia was no longer completed 3 days later, and the miracidia were deformed severely 7 days later. The atrophy of miracidia was not obvious in the blank controls. CONCLUSION: The schistosome miracidia and embryonic membrane can be damaged by the calcium cyanamide synthetic drug, and worse damaged with time extending.
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Enfermedades de los Bovinos/parasitología , Cianamida/farmacología , Óvulo/crecimiento & desarrollo , Schistosoma japonicum/efectos de los fármacos , Esquistosomiasis Japónica/veterinaria , Esquistosomicidas/farmacología , Animales , Bovinos , Cianamida/síntesis química , Heces , Femenino , Masculino , Óvulo/efectos de los fármacos , Schistosoma japonicum/crecimiento & desarrollo , Esquistosomiasis Japónica/parasitología , Esquistosomicidas/síntesis químicaRESUMEN
Coverage of migrating people in schistosomiasis control program is a growing concern in China. Schistosomiasis caused by Schistosoma japonicum is still one of the major infectious diseases of public health importance in China though tremendous efforts have been made to control the transmission over the past decades. Along with the rapid social-economic development, migrant population has been remarkably increasing across the country. The infected migrants may introduce a new souse of infection to endemic areas or the areas where the transmission had been controlled or interrupted but the intermediate host Oncomelania snail is still present. Preliminary studies for surveillance on schistosomiasis prevalence in migrants were reported, but there is little basic information provided. We carried out an investigation on the prevalence in immigrants, emigrants and permanent residents in three villages of Hunan province located in the main endemic area of lake region, and analyzed the potential impact of migration on control practice. In the study villages, the migrant population accounts for 53.6% of the total. Schistosoma infection was detected by modified Kato-Katz method and miracidium hatching test. Questionnaire survey was conducted comprising knowledge of disease and its transmission, water contact, personal protective measures, and whether examined and treated after water contact. The survey indicated that the migrants and permanent residents had similar life style, and the majority of them experienced water contact in agricultural work or routine life activities. However, the infection rate in immigrants was significantly higher than that in permanent residents. It was also found that the migrants had significantly less knowledge about the disease than the permanent residents, and took no personal protective measures. This is due to that the control program could not cover the migrants when they were absent at the time the program being implemented. The present study suggested that the surveillance and intervention for migrants, immigrants in particular, should be included and strengthened in schistosomiasis control program and a feasible scheme be developed.
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Schistosoma japonicum/efectos de los fármacos , Esquistosomiasis Japónica/epidemiología , Esquistosomiasis Japónica/prevención & control , Esquistosomicidas/uso terapéutico , Migrantes/estadística & datos numéricos , Adolescente , Adulto , Anciano , Animales , Niño , China/epidemiología , Manejo de la Enfermedad , Femenino , Humanos , Masculino , Tamizaje Masivo , Persona de Mediana Edad , Prevalencia , Esquistosomiasis Japónica/tratamiento farmacológico , Caracoles/parasitología , Adulto JovenRESUMEN
OBJECTIVE: To analyze the time and space aggregation of acute schistosome infections in marshland and lake areas in five provinces (Jiangsu, Anhui, Jiangxi, Hubei and Hunan province) from 2005 to 2012, so as to provide the evidence for establishing control strategies and taking effective control measures. METHODS: The data of patients with acute schistosome infection in marshland and lake areas in five provinces from 2005 to 2012 were collected and analyzed with the concentration ratio and circular distribution methods for the epidemic season features and time aggregation of the infection, and with the spatial autocorrelation analysis for the space aggregation of the infected cases. RESULTS: According to the concentration ratio, the occurrence of acute schistosome infection had strong seasonality, and the concentration ratio was 0.758; according to the circular distribution method, the peak day of acute schistosome infections was 10th, August. The spatial analysis suggested that the infected cases highly gathered around Poyang Lake, Dongting Lake and Yangtze River Basin in 23 counties of the five provinces, and the result of spatial autocorrelation analysis showed that the spatial autocorrelation index I was 0.16 (P = 0.01). CONCLUSION: The occurrence of acute schistosome infections in lake regions of the 5 provinces shows strong seasonality and space aggregation, therefore we can bring the control mark forward, and take targeted prevention and control measures in high aggregation areas of acute schistosomiasis.
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Lagos/parasitología , Schistosoma/fisiología , Esquistosomiasis/epidemiología , Análisis Espacio-Temporal , Humedales , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Niño , China/epidemiología , Análisis por Conglomerados , Femenino , Humanos , Masculino , Persona de Mediana Edad , Esquistosomiasis/prevención & control , Adulto JovenRESUMEN
OBJECTIVE: To investigate the schistosomiasis japonica infection and preventive knowledge of immigration population in Jinshan District, Shanghai so as to provide the evidence for improving the control work. METHODS: The immigration population from schistosomiasis endemic provinces and local people were screened by serum IHA screening for schistosome infection, and the positives were further examined by Kato-Katz technique and the miracidium hatching method. The schistosomiasis preventive knowledge and behaviors were investigated by questionnaires. RESULTS: A total of 579 were investigated with 348 immigration people and 231 local people, and among them, the male accounted for 72.0% and female accounted for 28.0%. In the immigration population, the main age group was 20-29 (56.0%), and 56.6% of the immigration had an education level at senior middle school or higher. The most proportion of immigration was from Anhui Province (36.2%). There were 4 IHA positive persons (1.15%) in the immigration, and 1 was positive in the stool test, and the schistosome infection rate was 0.29%. There were no positives in the local people. The schistosomiasis preventive knowledge of the immigration was generally poor, and some people' s behaviors of see doctor and medication were incorrect. CONCLUSION: There are schistosome infected persons among the immigration population from schistosomiasis endemic provinces, and their schistosomiasis prevention knowledge was poor, thus there is a schistosomiasis transmission risk.
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Emigración e Inmigración/estadística & datos numéricos , Conocimientos, Actitudes y Práctica en Salud , Esquistosomiasis Japónica/epidemiología , Esquistosomiasis Japónica/prevención & control , Adulto , Animales , China/epidemiología , Femenino , Humanos , Masculino , Schistosoma japonicum/aislamiento & purificación , Schistosoma japonicum/fisiología , Adulto JovenRESUMEN
Tropical diseases remain a major cause of morbidity and mortality in developing countries. Although combined health efforts brought about significant improvements over the past 20 years, communities in resource-constrained settings lack the means of strengthening their environment in directions that would provide less favourable conditions for pathogens. Still, the impact of infectious diseases is declining worldwide along with progress made regarding responses to basic health problems and improving health services delivery to the most vulnerable populations. The London Declaration on Neglected Tropical Diseases (NTDs), initiated by the World Health Organization's NTD roadmap, set out the path towards control and eventual elimination of several tropical diseases by 2020, providing an impetus for local and regional disease elimination programmes. Tropical diseases are often patchy and erratic, and there are differing priorities in resources-limited and endemic countries at various levels of their public health systems. In order to identify and prioritize strategic research on elimination of tropical diseases, the 'First Forum on Surveillance-Response System Leading to Tropical Diseases Elimination' was convened in Shanghai in June 2012. Current strategies and the NTD roadmap were reviewed, followed by discussions on how to identify and critically examine prevailing challenges and opportunities, including inter-sectoral collaboration and approaches for elimination of several infectious, tropical diseases. A priority research agenda within a 'One Health-One World' frame of global health was developed, including (i) the establishment of a platform for resource-sharing and effective surveillance-response systems for Asia Pacific and Africa with an initial focus on elimination of lymphatic filariasis, malaria and schistosomiasis; (ii) development of new strategies, tools and approaches, such as improved diagnostics and antimalarial therapies; (iii) rigorous validation of surveillance-response systems; and (iv) designing pilot studies to transfer Chinese experiences of successful surveillance-response systems to endemic countries with limited resources.
RESUMEN
Despite major successes in its control over the past 50years, schistosomiasis japonica continues to be a public health problem in the People's Republic of China (P.R. China). Historically, the major endemic foci occur in the lakes and marshlands along the Yangtze River, areas where transmission interruption has proven difficult. The current endemic situation may alter due to the closure of the Three Gorges Dam. Considerable environmental and ecological changes are anticipated that may result in new habitats for the oncomelanid intermediate snail host of Schistosoma japonicum (Sj), thereby increasing the risk of transmission. The current national control program for P.R. China involves a multi-component integrated strategy but, despite targeting multiple transmission pathways, certain challenges remain. As the Chinese government pushes towards elimination, there is a requirement for additional tools, such as vaccination, for long-term prevention. Whereas the zoonotic nature of schistosomiasis japonica adds to the complexity of control, it provides a unique opportunity to develop a transmission blocking vaccine targeting bovines to assist in the prevention of human infection and disease. Mathematical modelling has shown that control options targeting the various transmission pathways of schistosomiasis japonica and incorporating bovine vaccination, mass human chemotherapy and mollusciciding could lead to its elimination from P.R. China. Here we present the study design and baseline results of a four-year cluster randomised intervention trial we are undertaking around the schistosomiasis-endemic Dongting Lake in Hunan Province aimed at determining the impact on schistosome transmission of the multi-component integrated control strategy, including bovine vaccination using a heterologous "prime-boost" delivery platform based on the previously tested SjCTPI vaccine.
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Enfermedades de los Bovinos/parasitología , Niclosamida/farmacología , Praziquantel/uso terapéutico , Esquistosomiasis Japónica/prevención & control , Esquistosomiasis Japónica/veterinaria , Adolescente , Adulto , Animales , Bovinos , Enfermedades de los Bovinos/epidemiología , Enfermedades de los Bovinos/prevención & control , Niño , Preescolar , China/epidemiología , Esquema de Medicación , Femenino , Humanos , Lactante , Masculino , Moluscocidas/farmacología , Praziquantel/administración & dosificación , Esquistosomiasis Japónica/epidemiología , Esquistosomicidas/administración & dosificación , Esquistosomicidas/uso terapéutico , Factores de Tiempo , Vacunas/inmunología , Adulto JovenRESUMEN
The diagnosis of Schistosoma japonicum (Sj) infection in low prevalence areas of the People's Republic of China is challenging due to the sensitivity of the detection methods, leading to an underestimation of the disease burden. We compared the sensitivities of the miracidium hatching test (MHT) with the modified Kato-Katz method (KK) and the combination of the two methods (KK-MHT) to detect Sj infection in low prevalence areas of China. The stool samples of 3,853 residents from 8 villages with a light to moderate prevalence (0-23%) of Sj infection were examined by KK, MHT and KK-MHT. The findings were inconsistent. The KK-MHT conbination gave more positives than either the KK or MHT alone. Using the KK-MHT, we determined the missed rates with the KK (mR(K)) and MHT (mR(H)) to be 30.1% and 10.2%, respectively. At light prevalence sites (infection rate < 10%) the mR(K) was 60.6%, significantly higher than the mR(K) of 22.3% found at moderate prevalence sites (10-23%). However, the mR(H) at the light and moderate prevalence sites were 11.54% and 9.90%, respectively (p > 0.05). The combination KK-MHT had the best sensitivity in low Sj prevalence areas in China and the KK method alone was the least sensitive. Using KK alone as a screening method will result in an underestimation of Sj infection disease burden.
Asunto(s)
Recuento de Huevos de Parásitos/métodos , Schistosoma japonicum/aislamiento & purificación , Esquistosomiasis Japónica/diagnóstico , Animales , China/epidemiología , Ensayo de Inmunoadsorción Enzimática , Heces/parasitología , Humanos , Prevalencia , Esquistosomiasis Japónica/epidemiología , Esquistosomiasis Japónica/parasitología , Sensibilidad y Especificidad , Encuestas y CuestionariosRESUMEN
BACKGROUND: Despite significant, steady progress in schistosomiasis control in the People's Republic of China over the past 50 years, available data suggest that the disease has re-emerged with several outbreaks of acute infections in the early new century. In response, a new integrated strategy was introduced. METHODS: This retrospective study was conducted between Jan 2005 and Dec 2012, to explore the effectiveness of a new integrated control strategy that was implemented by the national control program since 2004. RESULTS: A total of 1,047 acute cases were recorded between 2005 and 2012, with an annual reduction in prevalence of 97.7%. The proportion of imported cases of schistosomiasis was higher in 2011 and 2012. Nine clusters of acute infections were detected by spatio-temporal analysis between June and November, indicating that the high risk areas located in the lake and marshland regions. CONCLUSION: This study shows that the new integrated strategy has played a key role in reducing the morbidity of schistosomiasis in the People's Republic of China.