Saint Lucia revisited

Core components, concepts and strategies for parasitic and vector-borne disease elimination with a focus on schistosomiasis: A landscape analysis

Efforts to control and eliminate human schistosomiasis have accelerated over the past decade. In a number of endemic countries and settings, interruption of schistosome transmission has been achieved. In others, Schistosoma infections continue to challenge program managers at different levels, from the complexity of the transmission cycle, over limited treatment options and lack of field-friendly accurate diagnostics, to controversy around adequate intervention strategies. We conducted a landscape analysis on parasitic and vector-borne disease elimination approaches with the aim to identify evidence-based strategies, core components and key concepts for achieving and sustaining schistosomiasis control and for progressing elimination efforts towards interruption of transmission in sub-Saharan Africa. A total of 118 relevant publications were identified from Web of Science, Pubmed and the grey literature and reviewed for their content. In addition, we conducted in-depth interviews with 23 epidemiologists, program managers, policymakers, donors and field researchers. Available evidence emphasizes the need for comprehensive, multipronged and long-term strategies consisting of multiple complementary interventions that must be sustained over time by political commitment and adequate funding in order to reach interruption of transmission. Based on the findings of this landscape analysis, we propose a comprehensive set of intervention strategies for schistosomiasis control and elimination. Before deployment, the proposed interventions will require review, evaluation and validation in the frame of an expert consultation as a step towards adaptation to specific contexts, conditions and settings. Field testing to ensure local relevance and effectiveness is paramount given the diversity of socio-ecological and epidemiological contexts.

This landscape analysis explored successful concepts, approaches and interventions of past and ongoing parasitic and vector-borne disease elimination efforts and programs with regard to relevance for progress in the elimination of human schistosome infections. Schistosomiasis is a disabling, water borne parasitic disease of public health concern with an estimated 250 million people infected worldwide. The long-term morbidity of this neglected tropical disease significantly impacts growth, cognition and socioeconomic development at all ages. Despite increased global efforts to control morbidity and advance elimination, challenges in view of the complex life cycle which involves freshwater sources, intermediate snail hosts and humans, remain. This calls for targeted interventions and concerted programs. According to the evidence from the literature and as proposed by a wide range of key informants, comprehensive, multipronged and long-term strategies supported by strong political commitment and adequate funding are required in order to achieve and sustain the set goals. Based on the findings, we propose here a comprehensive set of intervention strategies for schistosomiasis control and elimination for review and evaluation to inform implementation research needs and elimination program design.

Towards active community participation in dengue vector control: results from action research in Santiago de Cuba, Cuba

Community participation is advocated as essential for attaining effective dengue prevention, but knowledge of how to foster this is limited. In Santiago de Cuba, multiple small task forces were created at the neighbourhood level that included all stakeholders in the control of Aedes aegypti. The task forces assessed the perceived needs and elaborated action plans to promote specific behavioural change and to reduce environmental risks through social communication strategies and intersectoral local government activities. We monitored five dimensions of the participation process and assessed behavioural and environmental results and entomological outcomes. Participation was weak to good. At the household level, uncovered water storage containers decreased from 49.3% to 2.6% between 2000 and 2002, and removing larvicide from them dropped from 45.5% to 1%. There was a reduction of 75% in the absolute number of positive containers and a significant decrease from 1.23% to 0.35% in the house index. Local task forces, in which the interests of householders as well as vector control workers are directly represented, can lead to effective government-community partnerships that resolve problems of mutual concern.

Intersectoral coordination in Aedes aegypti control. A pilot project in Havana City, Cuba

Background The 55th World Health Assembly declared dengue prevention and control a priority and urged Member States to develop sustainable intersectoral strategies to this end. To provide evidence for the reorientation of the dengue prevention policy in Cuba, we launched an intervention study to document the effectiveness of a local-level intersectoral approach.

METHODS

We used a quasi-experimental design. Social scientists introduced participatory methods to facilitate dialogue in the biweekly meetings of the intersectoral Health Council of the intervention area. This council subsequently developed an intersectoral plan for dengue prevention, of which the core objective was to design and implement activities for communication and social mobilization. In the control area, routine dengue control activities continued without additional input. Knowledge, attitudes and perceptions of dengue, and entomological indices were compared inside and between the areas before and after the 1-year intervention period.

RESULTS

In the intervention area the Health Council elaborated an intersectoral plan for dengue prevention focused on source reduction. The Aedes aegypti control methods consisted in eliminating useless containers in the houses and surroundings, covering tanks, and cleaning public and inhabited areas. It was implemented through communication and social mobilization. The Health Council in the control area occasionally discussed dengue issues but did not develop a coordinated action plan. Good knowledge about breeding sites and disease symptoms increased significantly (by 49.7% and 17.1% respectively) in the intervention area as well as the proportion of respondents eliminating containers in and around their houses (by 44%). No changes were observed in the control area. The House Index in the intervention area was 3.72% at baseline and decreased to 0.61% after 1 year. In the control area it remained stable throughout the study period (1.31% and 1.65% respectively).

CONCLUSION

The introduction of a participatory approach by social scientists promotes changes in intersectoral management. This facilitates social mobilization which, in its turn, leads to significant changes in knowledge, attitudes and dengue-related practices in the population and eventually to more effective control of Ae. aegypti.