-
[show abstract]
[hide abstract]
ABSTRACT: Health education is an important component of efforts to control schistosomiasis. In China, while education programmes have been implemented intensively, few articles in recent years in either the Chinese or English literature report randomised, controlled interventions of the impacts on knowledge, attitudes and behaviours .Thus, we designed and carried out a cluster-randomised controlled education intervention trial that targeted 706 adults from rural areas in 28 villages in Sichuan, China. We evaluated the effects of the intervention on five endpoints: (1) schistosomiasis knowledge, (2) attitudes towards infection testing and treatment, (3) use of personal protective equipment (PPE), (4) reducing defecation in the field, and (5) reducing dermal contact with potentially contaminated water sources. The results indicated that people in both the intervention and control groups showed improvement in knowledge, attitudes and reduction in field-defecation in the follow-up surveys. However, there was little evidence that suggested statistically significant differences between the two groups regarding any endpoint. Participation in intervention classes was associated with age, gender, occupation and education level. Our study suggests short-term health education interventions may not be effective in improving schistosomiasis knowledge or in the adoption of health-protective behaviours. This might be partially due to the spontaneous learning process of people subject to repeated surveys and other disease control activities. Considering the difficulties of occupationassociated behaviour change and knowledge reinforcement in general, longer-term education programmes should be considered in the future.
Acta tropica 05/2013; · 2.22 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: BACKGROUND: In light of multinational efforts to reduce helminthiasis, we evaluated whether there exist high-risk subpopulations for helminth infection. Such individuals are not only at risk of morbidity, but may be important parasite reservoirs and appropriate targets for disease control interventions. METHODSPRINCIPAL FINDINGS: We followed two longitudinal cohorts in Sichuan, China to determine whether there exist persistent human reservoirs for the water-borne helminth, Schistosoma japonicum, in areas where treatment is ongoing. Participants were tested for S. japonicum infection at enrollment and two follow-up points. All infections were promptly treated with praziquantel. We estimated the ratio of the observed to expected proportion of the population with two consecutive infections at follow-up. The expected proportion was estimated using a prevalence-based model and, as highly exposed individuals may be most likely to be repeatedly infected, a second model that accounted for exposure using a data adaptive, machine learning algorithm. Using the prevalence-based model, there were 1.5 and 5.8 times more individuals with two consecutive infections than expected in cohorts 1 and 2, respectively (p<0.001 in both cohorts). When we accounted for exposure, the ratio was 1.3 (p = 0.013) and 2.1 (p<0.001) in cohorts 1 and 2, respectively. CONCLUSIONSSIGNIFICANCE: We found clustering of infections within a limited number of hosts that was not fully explained by host exposure. This suggests some hosts may be particularly susceptible to S. japonicum infection, or that uncured infections persist despite treatment. We propose an explanatory model that suggests that as cercarial exposure declines, so too does the size of the vulnerable subpopulation. In low-prevalence settings, interventions targeting individuals with a history of S. japonicum infection may efficiently advance disease control efforts.
PLoS Neglected Tropical Diseases 03/2013; 7(3):e2098. · 4.69 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Sensitive Schistosoma japonicum detection methods are needed to progress from schistosomiasis control to elimination. The sensitivity of the Kato-Katz thick smear and miracidium hatching tests decrease with infection intensity and serological tests cannot always identify current infections. We evaluated a fecal polymerase chain reaction (PCR) assay to detect S. japonicum infection in 106 humans and 8 bovines in China. The PCR was highly sensitive, detecting S. japonicum DNA at 0.5 eggs/g of stool. Comparing PCR examination of a single stool sample to the miracidium hatching test using three consecutive stool samples, more humans were hatching test positive (20%) than PCR positive (15%). However, two individuals were PCR positive in a village where no infections were detected by coprological methods. The sensitivity of PCR makes it a promising tool for schistosomiasis diagnostics and screening, although egg shedding variability and stool sample size present challenges for any detection method in low-transmission areas.
The American journal of tropical medicine and hygiene 10/2012; · 2.59 Impact Factor
-
Edmund Y W Seto,
Justin V Remais,
Elizabeth J Carlton, Shuo Wang,
Song Liang,
Paul J Brindley,
Dongchuan Qiu,
Robert C Spear,
Long-De Wang,
Tian-Ping Wang,
Hong-Gen Chen,
Xing-Qi Dong,
Li-Ying Wang,
Yang Hao,
Robert Bergquist,
Xiao-Nong Zhou
[show abstract]
[hide abstract]
ABSTRACT: Triggered by a fascinating publication in the New England Journal of Medicine detailing China's new multi-pronged strategy to control and eventually interrupt the transmission of Schistosoma japonicum, this PLoS Neglected Tropical Diseases Debate critically examines the generalizability and financial costs of the studies presented from the marshlands of the lake region. Edmund Seto from the University of California and colleagues emphasize that the epidemiology and control of schistosomiasis varies according to the social-ecological context. They conjecture that the successful intervention packages piloted in the lake region is not fully fit for the hilly and mountainous environments in Sichuan and Yunnan provinces, and hence call for more flexible, setting-specific, and less expensive control strategies. In response, Xiao-Nong Zhou from the National Institute of Parasitic Diseases at the Chinese Center of Disease Control and Prevention and colleagues explain the steps from designing pilot studies to the articulation and implementation of a new national control strategy through a careful process of scaling-up and adaptations. Finally, the two opponents converge. The need for integrated, intersectoral, and setting-specific control measures is stressed, supported by rigorous surveillance and continuous research. Experiences and lessons from China are important for shaping the schistosomiasis elimination agenda.
PLoS Neglected Tropical Diseases 10/2011; 5(10):e1372. · 4.69 Impact Factor
