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Background: The echinococcosis is prevalent in 10 provinces /autonomous region in western and northern China. Epidemiological survey of echinococcosis in China in 2012 showed the average prevalence of four counties in Tibet Autonomous Region (TAR) is 4.23%, much higher than the average prevalence in China (0.24%). It is important to understand the transmission risks and the prevalence of echinococcosis in human and animals in TAR., Methods: A stratified and proportionate sampling method was used to select samples in TAR. The selected residents were examined by B-ultrasonography diagnostic, and the faeces of dogs were tested for the canine coproantigen against Echinococcus spp. using enzyme-linked immunosorbent assay. The internal organs of slaughtered domestic animals were examined by visual examination and palpation. The awareness of the prevention and control of echinococcosis among of residents and students was investigated using questionnaire. All data were inputted using double entry in the Epi Info database, with error correction by double-entry comparison, the statistical analysis of all data was processed using SPSS 21.0, and the map was mapped using ArcGIS 10.1, the data was tested by Chi-square test and Cochran-Armitage trend test., Results: A total of 80 384 people, 7564 faeces of dogs, and 2103 internal organs of slaughtered domestic animals were examined. The prevalence of echinococcosis in humans in TAR was 1.66%, the positive rate in females (1.92%) was significantly higher than that in males (1.41%), (χ 2  = 30.31, P < 0.01), the positive rate of echinococcosis was positively associated with age (χ 2 trend  = 423.95, P < 0.01), and the occupational populations with high positive rates of echinococcosis were herdsmen (3.66%) and monks (3.48%). The average positive rate of Echinococcus coproantigen in TAR was 7.30%. The positive rate of echinococcosis in livestock for the whole region was 11.84%. The average awareness rate of echinococcosis across the region was 33.39%., Conclusions: A high prevalence of echinococcosis is found across the TAR, representing a very serious concern to human health. Efforts should be made to develop an action plan for echinococcosis prevention and control as soon as possible, so as to control the endemic of echinococcosis and reduce the medical burden on the population.

Background: Human cystic echinococcosis (CE) and alveolar echinococcosis (AE) are highly endemic in Tibetan communities of Sichuan Province. Previous research in the region indicated that domestic dog was the major source of human infection, and observations indicated that domestic dog could have more access to intermediate hosts of Echinococcus spp.: both domestic livestock (CE) viscera and small mammals (AE), in early winter and again in spring. We hypothesized that there would therefore be a significant increase in the risk of canine infection with Echinococcus spp. in these two seasons and conducted a reinfection study to investigate this further., Methods: Faecal samples were collected from owned dogs in seven townships in Ganze Tibetan Autonomous Prefecture (Sichuan Province, China), and Echinococcus spp. infection status was determined using copro-antigen ELISA. Dogs were sampled in April (spring), July (early summer), September/October (autumn/early winter) and December (winter) in 2009; and in April (spring) 2010. Dogs were treated with praziquantel following each of the five sample collections to eliminate any tapeworms. Information on dog sex, age and body weight was also collected. The t-test, Fisher's exact test, Poisson regression and logistic regression were used to compare means and prevalences, and to identify factors associated with infection status., Results: The proportion of female dogs was significantly lower than that of male dogs; female dogs had significantly higher (22.78 %) baseline copro-ELISA prevalence than males (11.88 %). Dog body weight, sex, age, county and previous infection status at any sampling point had no influence on the re-infection prevalence in general. Poisson regression did not found a significant influence on the re-infection prevalence due to different deworming/sampling time spans. Dogs exhibited significantly higher re-infection prevalences in spring and early summer of 2009 and in early winter between September/October and December of 2009, suggesting a higher infection pressure in these seasons comparing with other seasons., Conclusion: Following praziquantel treatment, dog body weight, sex, age, county, deworming time span and previous infection status at any sampling point had no influence on the re-infection prevalence in the region in general. The differences between re-infection prevalences were probably due to the seasonality in Echinoccocus spp. infection pressure in the region. Early winter, spring and early summer should be important seasons for optimal dog deworming intervention in these Tibetan communities.

Objective: To understand dog fecal contamination by Echinococcus in Lhoka Prefecture of Tibet and provide basis for development of prevention and control strategies., Methods: Survey spots were sampled around the Zhegu Village of Zhegu Town in Cuomei County of Tibet using the mechanical sampling method in May, 2015. The positions of spots, amount of dog feces, types of camps, pastures, terrains, vegetations and land cover, as well as information concerning the existence of household garbage, were recorded. The linear distance from survey spot to the center of the village was calculated. Dog feces were sampled in survey spot and examined the copro-antigen for Echinococcus contamination by ELISA. The distribution characteristics of fecal contamination were analyzed by chi-square test, Fisher′s exact test, Kruskal-Wallis test and Nemenyi test., Results: Seventy-nine survey spots were selected for sampling. A total of 226 feces samples were obtained in 37 of the spots. ELISA results showed that the copro-antigen positive rate was 23.9%（54/226）, the averaged density of feces and the averaged density of positive feces were 0.317 9/100 m2 and 0.075 9/100 m2, with a maximum of 2.555 6/100 m2 and 0.555 6/100 m2 respectively. The density of feces and the density of positive feces were both higher in summer camps（0.601 9/100 m2 and 0.157 4/100 m2 respectively） than in non-camps（0.170 2/100 m2 and 0.033 1/100 m2）（χ2=18.248 4，P<0.01；χ2=15.274 3，P<0.01）. In addition, the density of feces and the density of positive feces were both higher in survey spots with household garbage（0.679 0/100 m2, 0.177 0/100 m2） than in those without household garbage （0.130 3/100 m2 and 0.023 5/100 m2）（χ2=34.634 7，P<0.01；χ2=26.109 1，P<0.01）; as well as higher in survey spots ≥10 km from the center of the village（0.403 7/100 m2, 0.107 4/100 m2） than in those <10 km（0.265 3/100 m2, 0.056 7/100 m2）（χ2=4.432 7，P<0.05；χ2=4.045 5，P<0.05）., Conclusion: The Cuomei County of Tibet is facing a serious situation of dog fecal contamination by Echinococcus. Summer camps, areas with household garbage, and districts with a ≥10 km linear distance from the village center may provide reference for determining the regions for hydatidosis prevention and control.

Coproantigen test kits for Echinococcus spp. worms in dogs, designed for commercial use, were obtained from three different Chinese producers, and were compared with a laboratory kit using reagents from New Zealand. None of the three producers would provide details of their test validation. From a known set of dog faeces obtained at necropsy from infected and uninfected dogs, and from faeces collected from dogs necropsied in the field, results differed between the kits. For field material, the Tiankang kit showed the best specificity but lacked sensitivity. The Combined kit showed best sensitivity but lacked specificity. Results for the Haitai kit were intermediate. With samples from experimentally infected dogs, both the Haitai and Combined kits lacked sensitivity. Kits will need to be validated by the user before they can be relied on to predict progress in Echinococcus spp. control in China or in other countries.

Objective: To evaluate the effect of control pattern with an emphasis on canine deworming in a pilot of echinococcosis in highly endemic area of southern Qinghai Plateau., Methods: Four pasturing villages in Xiewu Township of Chengduo County were selected as pilot villages in August of 2008. Baseline survey on awareness of echinococcosis prevention knowledge among residents and status of dogs' infection (coproantigen ELISA) was carried out in the villages. After baseline survey, measures of minimizing the control unit, setting up 15th of each month as fixed canine purgation date (praziquantel 1-2 pill/dog), giving health education to residents, selecting and training control personnel, and mobilizing local residents to participate in control of echinococcosis were performed. In October of 2009, a survey was carried out with the same contents as baseline survey to evaluate the effect of the control pattern., Results: After intervention, the awareness rate on echinococcosis prevention knowledge in the residents increased from 76.1% (172/226) in 2008 to 98.8% (237/240) (chi2=55.6, P<0.01) . The positive rate of coproantigen ELISA for canine echinococcosis decreased from 32.6% (43/132) to 4.2% (5/120) (chi2=32.9, P<0.01)., Conclusion: The knowledge awareness on echinococcosis prevention in residents increased and infection rate in dogs decreased considerably after intervention.