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1.
ACS Omega ; 7(12): 10469-10475, 2022 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-35382280

RESUMEN

The energetic performance of hexanitrohexaazaisowurtzitane (CL-20) was modulated with two energetic coordination polymers (ECPs), [Cu(ANQ)2(NO3)2] and [Ni(CHZ)3](ClO4)2, in this study by a two-step method. First, tannic acid polymerized in situ on the surface of CL-20 crystals. Then, [Cu(ANQ)2(NO3)2] and [Ni(CHZ)3](ClO4)2 were hydrothermally formed on the surface of CL-20/TA, respectively. Explosion performance tests show that the impact sensitivity of the coated structure CL-20/TA/[Cu(ANQ)2(NO3)2] is 58% less than that of CL-20 with no energy decrease. On the other hand, CL-20/TA/[Ni(CHZ)3](ClO4)2 can be initiated by a low laser energy of 107.3 mJ (Nd:YAG, 1064 nm, 6.5 ns pulse width), whereas CL-20 cannot be initiated by even 4000 mJ laser energy. This study shows that it is feasible to modify the performance of CL-20 by introducing energetic CPs with certain properties, like high energy insensitive, laser-sensitive, etc., which could be a prospective method for designing high energy insensitive energetic materials in the future.

2.
China Tropical Medicine ; (12): 935-2022.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-979971

RESUMEN

@#Abstract: Objective To understand the changes of newly emerging and re-emerging snail areas in Anhui from 2017 to 2021 and analyze its related influencing factors, so as to provide scientific basis for formulating snail control strategies.   Methods According to the historical snail survey data, the information of newly emerging and re-emerging snails from 2017 to 2021 were collected, the causes for the formation of newly emerging and re-emerging snails flourish environments were investigated and analyzed retrospectively. Results During 2017-2021, in Anhui, the area with newly emerging snails was respectively 840.41 hm2, 559.14 hm2 (66.53%) in lake and marshland areas and 281.27 hm2 (33.47%) in hilly areas; the area of re-emerging snails was respectively 1 176.87 hm2, 669.39 hm2 (56.88%) in lake and marshland areas and 507.48 hm2 (43.12%) in hilly and mountainous areas. The sum of newly emerging snail area in Chizhou, Anqing and Wuhu accounted for 89.35% of all, the sum of re-emerging snail area accounted for 88.82%. In 2021, the areas with newly emerging and re-emerging snails peaked at 611.52 hm2 and 976.84 hm2, respectively. The newly emerging and re-emerging snail habitats were mainly distributed in the transmission interruption areas, accounting for 65.54% and 84.30%, respectively. The newly emerging and re-emerging snail habitats were mainly found in fluvial marsh, accounting for 65.54% and 52.12%, respectively. In recent 5 years, the longest time interval of re-emerging snails was more than 50 years. The main causes of newly emerging snails were natural factors such as flood disaster and snail drift along river system. Natural factors, such as flood disaster and snail drift along river system, were the main reasons for the newly emerging snail habitats, accounting for 71.44% and 21.75%, respectively. Human factors, such as soil extraction from snail habitats, construction of water conservancy facilities, farmland abandonment and seedling transplanting, could also lead to the newly emerging snail habitats. Flood disaster was the main cause of re-emerging snail habitats, accounting for 72.29%. In addition, the re-emerging snail habitats were caused by historical snail residue, soil collection in snail habitats for construction projects, land abandonment, seedling transplanting, prohibition of snail control in ecological protection areas, and construction of water conservancy facilities. Conclusions Flood disaster is an important factor for snail newly emerging and re-emerging. Human factors such as engineering construction and seedling transplanting are also easy to cause snail newly emerging and re-emerging. In order to timely detect and deal with newly emerging and re-emerging snail habitats and prevent snail diffusion, it is necessary to investigate snail distribution after flood disaster, the routine monitoring of historical snail habitats should be strengthened; in engineering construction and seedling transplanting, the disposal of soil with snails should be done well.

3.
Infect Dis Poverty ; 9(1): 63, 2020 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-32505216

RESUMEN

BACKGROUND: A steady progress on schistosomiasis control in the Peoples' Republic of China (P.R. China) was achieved and broadened into the twelve-year medium and long term national plan (MLNP) which marled the implementation of an integrated control strategy across all endemic areas in P.R. China in 2004. To understand the endemic trends of schistosomiasis to assess the effectiveness of an integrated strategy, we conducted an analysis of schistosomiasis surveillance data spanned from 2005 to 2015. METHODS: The schistosomiasis sentinel surveillance data from sentinel sites were collected and analyzed from 2005 to 2015. In these sentinel sites, residents aged 6 years or above were screened annually by indirect hemagglutination assay (IHA), while only antibody positives were followed by stool examination either Kato-katz method (KK) and/or hatching technique (HT). Domestic animals raised in sentinel sites were examined by HT for confirming the infection of schistosomes. Snail investigation was conducted each year through systematic sampling method combined with environmental sampling method. The snails collected from field were tested by microscopic dissection method. The infection rates of schistosomes in residents, domestic animals and snails, as well as the indicators reflecting the snails' distribution were calculated and analyzed. ANOVA analysis was used to examine the changes of the number of eggs per gram feces in population and Chi-square test was used to examine any change in proportions among groups. RESULTS: A total of 148 902 residents from sentinel sites attended this study and 631 676 blood samples were examined by IHA test during the 11 covered years. The annual average antibody positive rates presented a significant decrease trends, from 17.48% (95% CI: 17.20-17.75%) in 2005 to 5.93% (95% CI: 5.71-6.15%) (χ2 = 8890.47, P < 0.001) in 2015. During 2005-2015, the average infection rate of schistosomes in residents declined from 2.07% (95% CI: 1.96-2.17%) to 0.13% (95% CI: 0.09-0.16%), accompanied by significant decrease of infection intensity in population. In 2015, the stool positives were only found in farmers, fishermen and boatmen with infection rate of 0.16% (95% CI: 0.11-0.20%), 0.17% (95% CI: 0-0.50%) respectively. The infection rate of schistosomes in domestic animals dropped from 9.42% (538/5711, 95% CI: 8.66-10.18%) to 0.08% (2/2360, 95% CI: 0-0.20%) from 2005 to 2015. Infections were found in eight species of domestic animals at the beginning of surveillance while only two cattle were infected in 2015. Totally 98 ha of new snail habitats were found, while 94.90% (93/98) distributed in lake and marshland regions. The percentage of frames with snails decreased from 16.96% (56 884/33 5391, 95% CI: 16.83-17.09%) in 2005 to 4.28% (18 121/423 755, 95% CI: 4.22-4.34%) in 2014, with a slightly increase in 2015. Meanwhile, the infection rate of schistosomes in snails was decreased from 0.26% (663/256 531, 95% CI: 0.24-0.28%) to zero during 2005-2015. CONCLUSIONS: The infection rate of schistosomes declined significantly, providing evidence that the goal of the MLNP was achieved. Elimination of schistosomiasis as a public health problem defined as WHO was also reached in P.R. China nationwide. Surveillance-response system should be improved and strengthened to realize the final goal of schistosomiasis elimination.


Asunto(s)
Animales Domésticos , Esquistosomiasis , Vigilancia de Guardia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Niño , China/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Salud Pública , Esquistosomiasis/epidemiología , Esquistosomiasis/prevención & control , Esquistosomiasis/transmisión , Esquistosomiasis/veterinaria , Caracoles/parasitología , Adulto Joven
4.
Parasitol Int ; 67(5): 538-546, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29753097

RESUMEN

Anhui Province has been one of typical epidemic areas of schistosomiasis in East China as a wide range of large lake and marshland regions provide an ideal environment for growth and reproduction of the intermediate snail host. With the completion of the Yangtze River-Huaihe River Water Transfer Project (YHWTP), launched by the end of 2016, the epidemic areas are expected to expand and controlling schistosomiasis remains a challenge. Based on annual surveillance data at the county level in Anhui for the period 2006-2015, spatial and temporal cluster analyses were conducted to assess the pattern of risk through spatial (Local Moran's I and flexible scan statistic) and space-time scan statistic (Kulldorff). It was found that schistosomiasis sero-prevalence was dramatically reduced and maintained at a low level. Cluster results showed that spatial extent of schistosomiasis contracted, but snail distribution remained geographically stable across the study area. Clusters, both for schistosomiasis and snail presence, were common along the Yangtze River. Considering the effect of the ongoing YHWTP on the potential spread of schistosomiasis, Zongyang County and Anqing, which will be transected by the new water-transfer route, should be given a priority for strengthened surveillance and control. Attention should also be paid to Guichi since it is close to one of the planned inlets of the YHWTP.


Asunto(s)
Ríos/parasitología , Esquistosomiasis Japónica/epidemiología , Caracoles/parasitología , Análisis Espacio-Temporal , Distribución Animal , Animales , Anticuerpos Antihelmínticos/sangre , China , Análisis por Conglomerados , Conservación de los Recursos Hídricos , Estudios Transversales , Humanos , Prevalencia , Schistosoma japonicum , Estudios Seroepidemiológicos , Encuestas y Cuestionarios
5.
Artículo en Chino | MEDLINE | ID: mdl-26510352

RESUMEN

OBJECTIVE: To analyze the changes of schistosomiasis endemic situation in Anui Province from 2004 to 2014, so as to provide the evidence for formulating "The thirteenth five year" schistosomiasis control plan. METHODS: The information for schistosomiasis control and the data of the endemic surveillance of schistosomiasis were collected and analyzed for the changes of schistosomiasis endemic situation in Anhui Province from 2004 to 2014. RESULTS: The Oncomelania hupensis snail areas presented on a rising trend, and reached to the largest area with about 3.1 billon m2in 2011. However, the snail areas decreased from 2012, and reduced by 10.55% in 2012 compared with the areas in 2011, and reduced to the lowest level in 2014 in recent 10 years. The density of living snails presented a fluctuation situation from 2004 to 2008, and on a decreasing trend from 2008, and the density of living snails was below 1 snail/0.l i2 after 2011. The infection rate of snails remained stagnant state from 2004 to 2011, and decreased rapidly in 2012, and no schistosome infected snails were found in 2013 and 2014. The schistosome infection rate of residents decreased gradually, and the number of acute schistosomiasis was under 50 cases with scattered distribution after 2006, and no acute cases occurred in 2013 and 2014. The infection rate of livestock was above 1% from 2004 to 2011, and reduced to 0.55% in 2012, and it was the first time that the infection rate of livestock was lower than that of residents in the same year in 2014. The progress for achieving the goal of schistosomiasis transmission control accelerated after 2011, and the number of counties that reached the standard of schistosomiasis transmission controlled from 2012 to 2014 was 4, 9 and 14 and the number of townships was 33, 76 and 32, respectively. CONCLUSION: Schistosomiasis control has achieved remarkable effectiveness in Anhui Province, but there still exists hard work to consolidate the achievement and reach schistosomiasis transmission interrupted.


Asunto(s)
Esquistosomiasis/epidemiología , Animales , China/epidemiología , Reservorios de Enfermedades , Enfermedades Endémicas/estadística & datos numéricos , Humanos , Esquistosomiasis/prevención & control , Esquistosomiasis/transmisión , Caracoles , Factores de Tiempo
6.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 27(3): 263-7, 272, 2015 Jun.
Artículo en Chino | MEDLINE | ID: mdl-26510357

RESUMEN

OBJECTIVE: To investigate the status of Cryptosporidium infection in the population in the local area of Anhui Province, and discuss the risk factors of the infection, so as to provide the evidence for the prevention and treatment of cryptosporidiosis. METHODS: Qianshan County and Lingbi County of Anhui Province were selected as investigation spots, and the oocysts of Cryptosporidium in the feces of the investigation objects and the specific IgG antibody against Cryptosporidium in the serum were checked by using the pathogenic modified acid fast staining method and ELISA, respectively, so as to determine the status of Cryptosporidium infection in these investigation objects. At the same time, the questionnaire surveys were conducted in the investigation objects so as to know about the risk factors of Cryptosporidium infection. RESULTS: A total of 668 people were investigated in the two counties, 635 people received etiological examinations, and 15 people were positive with the positive rate of 2.36%; 642 people received serological examinations, and 140 people were positive with the positive rate of 21.81%; 628 people received pathogenic and serological examinations at the same time, and the examination results of the both methods showed that 12 people were positive (there were 4 people in Qianshan County and 8 people in Lingbi County) , and the positive rate was 1.94%. The rates of Cryptosporidium infection in the population of Qianshan County and Lingbi County were 1.24% (4/322) and 2.71% (8/295) respectively, and the difference had no statistical significance (P > 0.05). The single factor analysis found that the rate of Cryptosporidium infection was higher in the children and diarrhea patients; the multivariate logistics regression analysis indicated that the rate of Cryptosporidium infection was higher in the people who bred poultry and the diarrhea patients. CONCLUSIONS: The positive rate of serum antibody of Cryptosporidium in the population of the local area of Anhui Province is higher, which indicates that the previous infection is serious, and the rate of Cryptosporidium infection in human is relative to the age, diarrhea and whether there are poultries to be bred in the family, which is worthy of attention in the future prevention and treatment.


Asunto(s)
Criptosporidiosis/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Antiprotozoarios/sangre , Niño , Preescolar , China/epidemiología , Femenino , Humanos , Inmunoglobulina G/sangre , Modelos Logísticos , Masculino , Persona de Mediana Edad , Recuento de Huevos de Parásitos , Adulto Joven
7.
Artículo en Chino | MEDLINE | ID: mdl-26094433

RESUMEN

Oncomelania hupensis, which plays an important role in the transmission of schistosomiasis japonica, is the only intermediate host of Schistosoma japonicum, and carrying out studies on its subspecies differentiation and genetic variation will have an important significance for schistosomiasis control. In this paper, the research progress of taxonomy and discrimination techniques of O. hupensis is reviewed at four levels, namely the morphological level, the cellular level, the protein level, and the DNA molecule level, and DNA sequencing technology is considered as the ideal taxonomy and discrimination technique of O. hupensis and the future research emphasis.


Asunto(s)
Caracoles/clasificación , Animales , ADN/genética , Proteínas/genética , Caracoles/genética , Caracoles/metabolismo
8.
Artículo en Chino | MEDLINE | ID: mdl-26767252

RESUMEN

OBJECTIVE: To evaluate the effects of a novel molluscicide, the salt quinoid-2', 5-dichloro-4'-nitrosalicylanilide from niclosamide (LDS), with 10% wettable powder, in main schistosomiasis epidemic areas of China, including Hunan, Jiangxi, Hubei, Anhui, Jiangsu, Sichuan, Yunnan and Zhejiang Province. METHODS: In the immersion test, 6 effective concentrations of 10% LDS were tested respectively: 0.1, 0.2, 0.4, 0.6, 0.8, 1.0 g/m3 in the field; at the same time, 50% wettable powder of niclosamide ethanolamine salt (WPN) with effective concentrations of 1.0 g/m was used as the molluscicide control, and the fresh water as the blank control, then the mortality rates of 0. hupensis snails were recorded at 24 h, 48 h and 72 h after the immersion. In the spraying test and powder-spraying test, 5 effective dosages of 10% LDS were tested respectively: 0.2, 0.4, 0.6, 0.8, 1.0 g/m2, while 50% WPN 1.0 g/m2 was used as the molluscicide control, and the fresh water as the blank control in the field for 1 d, 3 d and 7 d, then the mortality rates of O. hupensis snails were recorded at 1 d, 3 d and 7 d after the spraying and powder-spraying. RESULTS: The snail mortality rates of LDS using the immersion test for 72 h were more than 95% in the field of eight provinces (0.1 g/m in Sichuan, Jiangxi, Jiangsu and Zhejiang provinces, 0.2 g/m3 in Yunnan, Hunan and Hubei provinces, and 0.4 g/min Anhui Province); the snail mortality rates of LDS using the spraying test for 7 d were more than 85% (0.2 g/m2 in Hunan, Hubei, Jiangxi and Zhejiang provinces, 0.4 g/m2 in Sichuan and Anhui provinces, 0.6 g/m2 in Yunnan and Jiangsu provinces). The snail mortality rates of LDS the powder-spraying test for 7 d were more than 85% (0.6 g/m2 in Yunnan, Sichuan, Hubei, Jiangxi, Anhui, Jiangsu and Zhejiang provinces). According to the standards of "Efficacy test methods and evaluation of molluscicide for pesticide registration (NY/T 1617-2008)", LDS is a qualified molluscicide. CONCLUSIONS: LDS has good molluscicidal effects through the immersion, spraying and powder-spraying test in the fields. It is suitable for a variety of environments to control O. hupensis snails of schistosomiasis endemic areas in China. The recommended dosages of LDS are 0.1-0.2 g/m3 by the immersion method, 0.2-0.4 g/m2 by the spraying method, and 0.4-0.6 g/m2 by the powder-spraying method in the fields.


Asunto(s)
Moluscocidas/farmacología , Esquistosomiasis/prevención & control , Caracoles , Animales , China/epidemiología , Esquistosomiasis/epidemiología , Esquistosomiasis/transmisión
9.
Artículo en Chino | MEDLINE | ID: mdl-26767262

RESUMEN

OBJECTIVE: To understand the epidemic situation of schistosomiasis in 27 counties (cities, districts) that reached the criteria of schistosomiasis infection controlled in Anhui Province. METHODS: According to the requirement of The National Assessment Scheme of Schistosomiasis, 81 administrative villages where the schistosomiasis epidemic situation was relatively heaver in above-mentioned 27 counties (1 village per town, 3 towns per county) were sampled and investigated. RESULTS: From 2012 to 2014, 81 villages were investigated, and 34,293 residents received the serum examinations, and 1,086 were positive with a positive rate of 3.17% (0.65%-9.58%), and the positives received stool examinations and the average stool positive rate was 0.37% (0-4.0%). The calculated prevalence of human infection was 0.01%. A total of 3 057 domestic animals were investigated including 438 cattle, 2,550 sheep, and 69 other animals, and no infections were detected. A total of 11,261 living Oncomelania hupensis snails were collected and detected, but no schistosome infected snails were found. Before this investigation, no infected snails were detected for more than 2 years [average 2.3 (2-6) years], and no acute schistosome infection cases were found for more than 2 years [average 4.9 (2-9) years]. CONCLUSION: The infection rates of schistosomiasis in residents and domestic animals are relatively low, and no schistosome infected snails are found in the regions.


Asunto(s)
Enfermedades Endémicas/estadística & datos numéricos , Esquistosomiasis/epidemiología , Adolescente , Adulto , Anciano , Animales , Niño , China/epidemiología , Humanos , Persona de Mediana Edad , Esquistosomiasis/prevención & control , Caracoles/parasitología
10.
Artículo en Chino | MEDLINE | ID: mdl-27089779

RESUMEN

At present, parasitic zoonoses in China are characterized by the reappearance of traditional parasitic zoonoses and constant emergence of new ones, which makes the prevention and control more difficult. In this review, we introduce the classification, epidemiological features, the endemic factors of the infection, as well as the principles and strategies for control, in the aim to provide hints on the control of such diseases in the future.


Asunto(s)
Zoonosis , Animales , China , Prevalencia
11.
Parasit Vectors ; 7: 578, 2014 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-25491192

RESUMEN

BACKGROUND: Marching towards the elimination of schistosomiasis in China, both the incidence and prevalence have witnessed profound decline over the past decades, with the strategy shifting from morbidity control to transmission control. The current challenge is to find out hotspots of transmission risk for precise targeted control in low-prevalence areas. This study assessed the risk at the village level, using the spatial and temporal characteristics of Schistosomiasis japonica in Anhui province from 2006 to 2012. METHOD: The comprehensive database was generated from annual surveillance data at village level in Anhui province between 2006 and 2012, comprising schistosomiasis prevalence among humans and cattle, occurrence rate of infected environments and incidence rate of acute schistosomiasis. The database parameters were matched with geographic data of the study area and fine scale spatial-temporal cluster analysis based on retrospective space-time scan statistics was used to assess the clustering pattern of schistosomiasis. The analysis was conducted by using SaTScan 9.1.1 and ArcGIS 10.0. A spatial statistical modelling was carried out to determine the spatial dependency of prevalence of human infection by using Geoda 1.4.3. RESULT: A pronounced decline was found in the prevalence of human infection, cattle infection, occurrence rate of environment with infected vector snails and incidence rate of acute schistosomiasis from 2006 to 2012 by 48.6%, 71.5%, 91.9% and 96.4%, respectively. Meanwhile, all 4 indicators showed a statistically significant clustering pattern both in time and space, with a total of 16, 6, 8 and 4 corresponding clustering foci found respectively. However, the number of clustering foci declined with time, and none was found after year 2010. All clustering foci were mainly distributed along the Yangtze River and its connecting branches. The result shows that there is a direct spatial relationship between prevalence of human infection and the other indicators. CONCLUSION: A decreasing trend in space-time clustering of schistosomiasis endemic status was observed between 2006 and 2012 in Anhui province. Nevertheless, giving the complexity in schistosomiasis control, areas within the upper-stream of Yangtze River in Anhui section and its connecting branches should be targeted for effective implementation of control strategies in the future.


Asunto(s)
Enfermedades de los Bovinos/epidemiología , Schistosoma japonicum/fisiología , Esquistosomiasis Japónica/epidemiología , Esquistosomiasis Japónica/veterinaria , Animales , Bovinos , Enfermedades de los Bovinos/parasitología , China/epidemiología , Humanos , Modelos Estadísticos , Estudios Retrospectivos , Schistosoma japonicum/aislamiento & purificación , Esquistosomiasis Japónica/parasitología , Caracoles/parasitología , Análisis Espacio-Temporal
12.
Artículo en Chino | MEDLINE | ID: mdl-25782239

RESUMEN

In this study, we summarized the results from the retrospective investigation on endemic situation of schistosomiasis that was implemented in nine provinces (autonomous region), China in 2009, demonstrated the role of these retrospective investigations in accelerating the progress of schistosomiasis control in China, and clarified the great significance of the investigation for summarizing the experiences for the control of schistosomiasis, and analyzing the changing patterns and affecting factors of endemic status of schistosomiasis in China. In addition, these retrospective investigations provide reliable evidence for revising the Criteria of Schistosomiasis Control and Elimination, and for the more accurate and scientific assessment of the effectiveness of schistosomiasis control in China.


Asunto(s)
Esquistosomiasis/prevención & control , Animales , China/epidemiología , Humanos , Estudios Retrospectivos , Schistosoma/fisiología , Esquistosomiasis/epidemiología , Esquistosomiasis/parasitología , Esquistosomiasis/transmisión
13.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 26(5): 482-5, 490, 2014 Oct.
Artículo en Chino | MEDLINE | ID: mdl-25782240

RESUMEN

OBJECTIVE: To understand the variation rules of schistosomiasis endemic situation before and after schistosomiasis transmission controlled or interrupted, so as to provide the evidence for the consolidation of control achievements. METHODS: In Anhui Province, 3 counties reaching the criteria of schistosomiasis transmission controlled or interrupted were selected and their historical endemic data were collected and analyzed statistically from 10 years before the schistosomiasis transmission controlled to 2008. RESULTS: In Tianchang City, the Oncomelania hupensis snail area was 3.54 hm2 in a part of the lake marshland in the year reaching the criteria of transmission controlled (1998), and no snails were found in the year of transmission interrupted (2008). No stool-test-positive resident was detected except there were 58 acute schistosomiasis cases in 1993, and the sero-test-positive rate of local residents remained at low levels (0-1.55%). In Taihu County, the snail area was 0.84 hm2 accounting for 0.06% of its historical accumulative snail areas in the year of transmission controlled (1971) , and no snails were found three years before the transmission interrupted (1983). However, the schistosomiasis endemic rebounded 12 years later (1995), there was an outbreak of acute schistosome infections (73 cases), and the snail area increased again to 133.7 hm2 accounting for 2.91% of historical accumulative snail areas. After that, the snail area kept on rising and the infection rates of residents and bovine remained higher than 1%. In Guangde County, the snail area was 32.4 hm2 accounting for 1.90% of its historical accumulative snail areas in the year of transmission controlled (1995). After that, the snail area increased progressively, and the schistosomiasis endemic rebounded and there were acute schistosome infections 5 years later. The Spearman tests showed that the sero-test-positive rate (Tianchang City) and the stool-test-positive rates of residents and bovine (Taihu County) had positive correlations with the snail areas (r = 0.582, 0.401, 0.596, all P < 0.05). CONCLUSION: The snail status is a key for the consolidation of schistosomiasis transmission controlled and interrupted. Therefore, a valid surveillance system of snail situation should be established as quickly as possible.


Asunto(s)
Enfermedades de los Bovinos/epidemiología , Enfermedades de los Bovinos/prevención & control , Control de Enfermedades Transmisibles , Esquistosomiasis/epidemiología , Esquistosomiasis/prevención & control , Esquistosomiasis/veterinaria , Adolescente , Adulto , Anciano , Animales , Bovinos , Enfermedades de los Bovinos/parasitología , Enfermedades de los Bovinos/transmisión , Niño , China/epidemiología , Reservorios de Enfermedades/parasitología , Enfermedades Endémicas/prevención & control , Femenino , Humanos , Masculino , Persona de Mediana Edad , Schistosoma/fisiología , Esquistosomiasis/transmisión , Caracoles/crecimiento & desarrollo , Caracoles/parasitología , Adulto Joven
14.
Artículo en Chino | MEDLINE | ID: mdl-24358740

RESUMEN

OBJECTIVE: To explore the application of space-time scan statistics in the early warning of distribution of schistosome infected Oncomelania hupensis snails. METHODS: The data of distribution of infected snails in Anhui Province from 2006 to 2012 were collected, and a spatial database was established by ArcGIS 9.3. The prospective spatial-temporal cluster analysis was done by SaTscan 9.1.1 at the village level. RESULTS: Four space-time clusters, which were distributed over the Yangtze River and its branch rivers, were detected. CONCLUSION: The space-time scan statistics could detect the distribution of infected snails early, and the space-time clusters found were the key and difficult points of schistosomiasis control in Anhui Province.


Asunto(s)
Reservorios de Enfermedades/parasitología , Sistemas de Información Geográfica , Schistosoma/fisiología , Esquistosomiasis/prevención & control , Caracoles/parasitología , Animales , China/epidemiología , Esquistosomiasis/epidemiología , Esquistosomiasis/parasitología
15.
Infect Dis Poverty ; 2(1): 18, 2013 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-23971713

RESUMEN

BACKGROUND: Parasite infections often result in a switch of the human body's predominant immune reaction from T-helper 1 (Th1)-type to Th2-type. Hence, parasite infections are widely expected to accelerate the progression of human immunodeficiency virus (HIV) infections to acquired immunodeficiency syndrome (AIDS). In the People's Republic of China, both parasitic diseases and AIDS are epidemic in certain rural areas, and co-infections are relatively common. However, no population-based studies have yet investigated the frequency of HIV and parasite co-infections, and its effects on immune responses. We studied (1) the immune status of an HIV-infected population, and (2) the effect of co-infection of HIV and intestinal parasites on selected parameters of the human immune system. METHODS: A total of 309 HIV-infected individuals were recruited and compared to an age-matched and sex-matched control group of 315 local HIV-negative individuals. Questionnaires were administered to all participants to obtain information on sociodemographic characteristics, sanitation habits, family income, and recent clinical manifestations. Two consecutive stool samples and 10 ml samples of venous blood were also collected from each individual for the diagnosis of parasite infections and quantitative measurements of selected cytokines and CD4+ T-lymphocytes, respectively. RESULTS: During the study period, 79 HIV-infected individuals were not under highly active antiretroviral therapy (HAART) and were thus included in our analysis; the prevalence of intestinal helminth infections was 6.3% and that of protozoa was 22.8%. The most common protozoan infections were Blastocystis hominis (B. hominis) (13.9%) and Cryptosporidium spp. (10.1%). The prevalence of Cryptosporidium spp. in HIV-infected individuals was significantly higher than that in HIV negative individuals (P < 0.05). Compared to the non-co-infected population, no significant difference was found for any of the measured immunological indicators (P > 0.05). However, the following trends were observed: IFN-γ levels were lower, but the IL-4 level was higher, in the population co-infected with HIV and helminths. In the population co-infected with HIV and B. hominis, the IL-2 level was higher. The population co-infected with HIV and Cryptosporidium spp. had markedly lower CD4+ T-lymphocyte counts. CONCLUSION: According to the immunologic profile, co-infection with helminths is disadvantageous to HIV-infected individuals. It was associated with a shift in the Th1/Th2 balance in the same direction as that caused by the virus itself, which might indicate an acceleration of the progress from an HIV infection to AIDS. Co-infection with Cryptosporidium spp. was not associated with a significant change in immune factors but co-infection with Cryptosporidium spp. was associated with a reduced level of CD4 + T-lymphocytes, confirming the opportunistic nature of such infections. Co-infection with B. hominis, on the other hand, was associated with an antagonistic shift in the immunological profile compared to an HIV infection.

16.
J Ovarian Res ; 6(1): 58, 2013 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-23962187

RESUMEN

BACKGROUND: To investigate the value of diffusion-weighted imaging (DWI) at 3.0 T (3T), and especially the apparent diffusion coefficient (ADC), in discriminating ovarian thecoma from other adnexal solid masses. METHODS: Eighteen thecomas or fibrothecomas, 14 ligamentous leiomyomas, and 24 other ovarian solid tumors underwent prospective DWI magnetic resonance imaging (MRI) in addition to routine MRI on a 3T MRI machine. The baseline characteristics, components, and conventional MRI and DWI-MRI signals for the thecomas were recorded. The ADC values (ADCs) were measured for each group and compared. RESULTS: The thecomas often appeared as homogeneous isointensity (17/18) on T1-weighted images (T1WI; 11/18) or T2WI (11/18) on DWI-MRI, with minor (9/18) or mild (6/18) enhancement. The mean ADC value for thecoma (1.20 ± 0.45 × 10-3 mm2/s) was almost equal to that of the other solid ovarian masses (1.26 ± 0.51 × 10-3 mm2/s), but lower than that for leiomyoma (1.48 ± 0.42 × 10-3 mm2/s), although not significantly so. There was a significant difference (p = 0.043) in the ADCs of the benign ovarian solid masses (1.16 ± 0.47 × 10-3 mm2/s) and leiomyomas (1.48 ± 0.42 × 10-3 mm2/s). CONCLUSIONS: There is no significant difference in ADC between thecoma and other adnexal solid masses, but the ADCs of thecomas are lower than those of leiomyomas.

17.
Proc Natl Acad Sci U S A ; 110(28): 11457-62, 2013 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-23798418

RESUMEN

Understanding disease transmission dynamics in multihost parasite systems is a research priority for control and potential elimination of many infectious diseases. In China, despite decades of multifaceted control efforts against schistosomiasis, the indirectly transmitted helminth Schistosoma japonicum remains endemic, partly because of the presence of zoonotic reservoirs. We used mathematical modeling and conceptual frameworks of multihost transmission ecology to assess the relative importance of various definitive host species for S. japonicum transmission in contrasting hilly and marshland areas of China. We examine whether directing control interventions against zoonotic reservoirs could further reduce incidence of infection in humans or even eliminate transmission. Results suggest that, under current control programs, infections in humans result from spillover of transmission among zoonotic reservoirs. Estimates of the basic reproduction number within each species suggest that bovines (water buffalo and cattle) maintained transmission in the marshland area and that the recent removal of bovines from this area could achieve local elimination of transmission. However, the sole use of antifecundity S. japonicum vaccines for bovines, at least at current efficacies, may not achieve elimination in areas of comparable endemicity where removal of bovines is not a feasible option. The results also suggest that rodents drive transmission in the hilly area. Therefore, although targeting bovines could further reduce and potentially interrupt transmission in marshland regions of China, elimination of S. japonicum could prove more challenging in areas where rodents might maintain transmission. In conclusion, we show how mathematical modeling can give important insights into multihost transmission of indirectly transmitted pathogens.


Asunto(s)
Schistosoma japonicum/aislamiento & purificación , Esquistosomiasis/parasitología , Animales , Bovinos , China , Esquistosomiasis/transmisión
18.
Artículo en Chino | MEDLINE | ID: mdl-23687801

RESUMEN

Based on the historical background for revision of the Control and Elimination Criteria for Schistosomiasis for 6 times, and the role of the criteria in promotion of national schistosomiasis control program of China at various stages, the present study demonstrated the necessity of further revision of the control criteria in the current schistosomiasis elimination program. In addition, the background for revision of the novel version of the Control and Elimination Criteria for Schistosomiasis was illustrated based on literature review, retrospective survey, expert argumentation and index improvement.


Asunto(s)
Aceleración , Control de Enfermedades Transmisibles/normas , Erradicación de la Enfermedad/normas , Guías de Práctica Clínica como Asunto/normas , Esquistosomiasis/prevención & control , China , Recolección de Datos , Documentación , Testimonio de Experto , Humanos , Estándares de Referencia , Estudios Retrospectivos
19.
Artículo en Chino | MEDLINE | ID: mdl-23687802

RESUMEN

OBJECTIVE: 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). METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.


Asunto(s)
Enfermedades Endémicas/estadística & datos numéricos , Esquistosomiasis/epidemiología , Encuestas y Cuestionarios , Control de Enfermedades Transmisibles/normas , Control de Enfermedades Transmisibles/estadística & datos numéricos , Erradicación de la Enfermedad/normas , Erradicación de la Enfermedad/estadística & datos numéricos , Testimonio de Experto , Humanos , Estándares de Referencia , Reproducibilidad de los Resultados , Esquistosomiasis/prevención & control , Estadística como Asunto
20.
Artículo en Chino | MEDLINE | ID: mdl-23687824

RESUMEN

This paper reviews the researches related to the reservoir hosts of Schistosoma japonicum, including bovine, sheep, dog, cat and wild mouse. Combined with the implementation of the comprehensive control strategy with an emphasis on infection source control in current, it puts forward several future research directions under the condition that the effects of people and bovine as infection sources weakened gradually, such as revaluation on the actual transmission capacity of non-bovine livestock, for example, sheep, dog, pig and wild mouse, as well as discussion on some transmission threshold values in the infection link of Oncomelania snails.


Asunto(s)
Interacciones Huésped-Parásitos , Schistosoma japonicum/fisiología , Esquistosomiasis Japónica/transmisión , Animales , Humanos , Especificidad de la Especie
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