Community and School-Based Health Education for Dengue Control in Rural Cambodia: A Process Evaluation

Dengue fever continues to be a major public health problem in Cambodia, with significant impact on children. Health education is a major means for prevention and control of the National Dengue Control Program (NDCP), and is delivered to communities and in schools. Drawing on data collected in 2003–2004 as part of an ethnographic study conducted in eastern Cambodia, we explore the approaches used in health education and their effectiveness to control dengue. Community health education is provided through health centre outreach activities and campaigns of the NDCP, but is not systematically evaluated, is under-funded and delivered irregularly; school-based education is restricted in terms of time and lacks follow-up in terms of practical activities for prevention and control. As a result, adherence is partial. We suggest the need for sustained routine education for dengue prevention and control, and the need for approaches to ensure the translation of knowledge into practice

Effectiveness of dengue control practices in household water containers in Northeast Thailand

OBJECTIVE: To investigate the influence of larval control methods (using temephos, keeping fish and covering containers with lids), water use and weekly cleaning of containers on the presence of Aedes aegypti larvae in water-storage containers in rural and urban households in Khon Kaen province. METHOD: Cross-sectional questionnaire survey and larval survey covered 966 households and 5821 containers were inspected. RESULT: In rural and urban areas larval control was patchy and often ineffective. Consequently, the mosquito indices exceed the target indices for dengue control with the Breteau Indices of 201 and 113, and Container Indices of 25 and 28 in rural and urban areas, respectively. The containers most frequently infested with larvae were rectangular cement containers storing water for bathing (rural: 37.2%; urban: 35%) and flushing the toilets (rural: 35.7%; urban: 34.3%). Keeping fish [adjusted odds ratio (AOR): 0.08-0.16] was the most effective methods of control. Correctly covering containers with lids was similarly effective (AOR: 0.10-0.25) when used on jars for storing drinking water. However, frequent use of containers reduced the effectiveness of lids. Temephos was effective only in dragon jars in urban areas (AOR: 0.46) where a standard package of temephos were available. Weekly cleaning of containers was an effective method for larval control in most types of containers. A combination of control methods increased effectiveness. CONCLUSION: This study highlights the complex interaction of household water use and larval control practices as well as the importance of determining the most effective control measures compatible with water practices for implementing control promotion

Aboriginal and invasive rats of Genus Rattus as hosts of infectious agents

From the perspective of ecology of zoonotic pathogens, the role of the Old World rats of the genus Rattus is exceptional. The review analyzes specific characteristics of rats that contribute to their important role in hosting pathogens, such as host-pathogen relations and rates of rat-borne infections, taxonomy, ecology, and essential factors. Specifically the review addresses recent taxonomic revisions within the genus Rattus that resulted from applications of new genetic tools in understanding relationships between the Old World rats and the infectious agents that they carry. Among the numerous species within the genus Rattus, only three species-the Norway rat (R. norvegicus), the black or roof rat (R. rattus), and the Asian black rat (R. tanezumi)-have colonized urban ecosystems globally for a historically long period of time. The fourth invasive species, R. exulans, is limited to tropical Asia-Pacific areas. One of the points highlighted in this review is the necessity to discriminate the roles played by rats as pathogen reservoirs within the land of their original diversification and in regions where only one or few rat species were introduced during the recent human history. (Résumé d'auteur