SUPPORT Summaries
Evidence of the effects of health system interventions
for low- and middle-income countries
Evidence of the effects of health system interventions
for low- and middle-income countries
May, 2017 - SUPPORT Summary of a systematic review | print this article | download PDF
Dengue is an infectious disease transmitted by mosquitoes. Dengue has dramatic negative impacts on health, the environment and the economy, particulary in the tropics. The use of community-based dengue control programmes has increased in the last few decades in order to address this major public health problem.
Key messages
A summary of studies addressing a clearly formulated question that uses systematic and explicit methods to identify, select, and critically appraise the relevant research, and to collect and analyse data from the included studies.
SUPPORT – was an international project to support the use of policy relevant reviews and trials to inform decisions about maternal and child health in low- and middle-income countries, funded by the European Commission (FP6) and the Canadian Institutes of Health Research.
Community oriented activities for dengue control have received increased attention in the last few decades. These efforts have included multi-component interventions to reduce larval, and ultimately adult, mosquito vector populations through chemical, biological and physical means as well as behavioural change interventions at the community level.
In this review, a community-based dengue control intervention was defined as any intervention in which at least one component targeted the community (e.g., educational meetings, involvement of local leaders) and whose aim was to reduce the incidence of dengue disease or infestation of communities with Aedes mosquitoes (as measured by any entomological index).
| Review objectives: To assess the effectiveness of community-based interventions in reducing vector populations for dengue control. | ||
| Type of | What the review authors searched for | What the review authors found |
|---|---|---|
| Study designs & interventions | Randomised trials, non-randomised trials, controlled before-after studies and interrupted time series studies of community-based interventions aimed at reducing vector populations for dengue control. |
11 included studies: 2 randomised trials, 6 controlled before-after studies and 3 interrupted time series studies assessing community-based dengue control interventions alone (5 studies); combined with chemical larvicides (2 studies); combined with fish and chemical larvicides (2 studies); and combined with larvae-eating crustaceans (Mesocyclops copepods) (2 studies).
Studies used educational materials (7 studies); educational meetings such as workshops (9 studies); and educational outreach visits (8 studies). Studies described the involvement of local opinion leaders (6 studies) and national institutions (5 studies), or the use of mass media (5 studies). |
| Participants | Community people and professionals serving the community. |
Household inhabitants (mostly housewives), the elderly, children, health committees, healthcare personnel, government officers, teachers and community organisations. |
| Settings | Community. |
Five studies were carried out in the Americas: Honduras (3), Mexico (1), and Cuba (1). Six studies were carried out in Asia: Vietnam (2), Thailand (1), Taiwan (1), French Polynesia (1), Fiji Islands (1). |
| Outcomes | Incidence of dengue disease or infestation of the community with Aedes mosquitoes. |
Classical entomological/larval indices such as the House Index (HI), the Container Index (CI) and the Breteau Index (BI) – all measures of larvae infestation in the home or in water containers; seroconversion or incidence of dengue disease. |
| Date of most recent search: March 2005 | ||
| Limitations: This is a well-conducted systematic review with only minor limitations. | ||
Heintze C, Velasco Garrido M, Kroeger A. What do community-based dengue control programmes achieve? A systematic review of published evaluations. Transactions of the Royal Society of Tropical Medicine and Hygiene.2007;101(4):317-325.
High: This research provides a very good indication of the likely effect. The likelihood that the effect will be substantially different† is low.
Moderate: This research provides a good indication of the likely effect. The likelihood that effect will be substantially different† is moderate.
Low: This research provides some indication of the likely effect. Howevver, the likelihood that it will be substantially different† is high.
Very low: This research does not provide a reliable indication of the likely effect. The likelihood that the effect will be substantially different† is very high.
* This is sometimes referred to as 'quality of evidence' or 'confidence in the estimate'.
† Substantially different = a large enough difference that it might affect a decision.
See last page for more information.
11 studies assessed community-based dengue control interventions alone or combined with other interventions. The studies varied with respect to target group, the interventions delivered, the length of the observation period after the intervention and the control groups used. Most studies compared intervention communities with ‘untreated’ control communities or did not describe what was done in the control communities.
Five studies from Cuba, the Fiji Islands and Honduras (3 studies) assessed community-based programmes. These programmes included a mix of educational meetings, educational materials, the involvement of local opinion leaders and other stakeholders and the use of mass media for educational messages.
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Multi-component community-based dengue control programmes |
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People Elderly people, children, women, health committees Settings Communities Intervention Multi-component community-based dengue control programmes. Interventions included a mix of educational meetings, involvement of local opinion leaders and national institutions, mass media communication, educational materials and educational outreach visits Comparison Usual practice (1 study); not specified (3 studies); not applicable (1 study) |
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| Outcomes | Impact | Certainty of the evidence (GRADE) |
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Mosquito larval indices |
Multi-component community-based dengue control programmes may reduce mosquito larval indices |
Low |
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GRADE: GRADE Working Group grades of evidence (see above and last page) |
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Chemical larvicides are used to eliminate mosquito larvae. Two studies from Mexico and Thailand evaluated programmes combining chemical larvicide use with multi-component community-based dengue control programmes.
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Multi-component community-based dengue control programmes combined with the use of chemical larvicides |
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People Household inhabitants, healthcare personnel, government officers, schoolchildren, teachers and community organisations Settings Communities Intervention Multi-component community-based dengue control programmes (including educational materials and meetings, educational outreach visits, mass media communication and involvement of local opinion leaders and national institutions) combined with the use of chemical larvicides Comparison No programme or not applicable |
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| Outcomes | Impact | Certainty of the evidence (GRADE) |
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Mosquito larval indices |
Multi-component community-based dengue control programmes combined with the use of chemical larvicides may reduce mosquito larvel indices. One study suggested that this combination may be less effective than community-based control programmes alone. |
Low |
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GRADE: GRADE Working Group grades of evidence (see above and last page) |
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Larvae-eating fish can be used to eliminate mosquito larvae. Two studies from French Polynesia and Taiwan evaluated programmes combining fish and chemical larvicide use with multi-component community-based dengue control programmes.
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Multi-component community-based dengue control programmes combined with fish and chemical larvicides |
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People Household inhabitants, teachers Settings Communities Intervention Multi-component community-based dengue control programmes (including educational materials and meetings and educational outreach visits) combined with fish and chemical larvicides Comparison Not specified |
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| Outcomes | Impact | Certainty of the evidence (GRADE) |
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Mosquito larval indices |
Multi-component community-based dengue control programmes combined with fish and chemical larvicides may reduce mosquito larval indices |
Low |
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GRADE: GRADE Working Group grades of evidence (see above and last page) |
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Crustaceans that eat mosquito larvae (Mesocyclops copepods ) can be easily harvested, bred and released into freshwater containers inhabited by Aedes aegypti mosquito larvae. It is possible to teach schoolchildren to recognize and collect Mesocyclops so that communities are able to undertake and sustain mosquito control themselves. Two studies from Vietnam evaluated programmes combining the use of crustaceans that eat mosquito larvae with multi-component community-based dengue control programmes.
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Multi-component community-based dengue control combined with the use of crustaceans that eat mosquito larvae ( Mesocyclops copepods) |
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People School children, teachers and women’s union Settings Communities Intervention Multi-component community-based dengue control programmes (including educational meetings and materials, educational outreach visits and involvement of local opinion leaders and national institutions) combined with copepods ( Mesocyclops) Comparison Not specified |
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| Outcomes | Impact | Certainty of the evidence (GRADE) |
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Mosquito larval indices |
Community-based dengue control programmes combined with the use of Mesocyclops copepods may reduce mosquito larval indices |
Low |
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Dengue incidence |
It is uncertain whether community-based dengue control programmes combined with the use of Mesocyclops copepods reduce dengue incidence |
Very low |
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GRADE: GRADE Working Group grades of evidence (see above and last page) |
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| Findings | Interpretation* |
|---|---|
| APPLICABILITY | |
| 10 of the 11 studies included in the systematic review were conducted in low- and middle-income countries. |
These findings are likely to be applicable to low-income country settings where dengue is prevalent. The acceptability, feasibility and costs of different community-based interventions for dengue vector control need to be considered in each setting. |
| EQUITY | |
| There was no information in the included studies regarding the differential effects of the interventions among disadvantaged populations. |
The interventions may decrease inequity in disadvantaged populations if resources to deliver the interventions are made available to those populations. Some community-based interventions (such as educational meetings, the involvement of local opinion leaders and the use of locally found crustaceans that eat mosquito larvae) may be implemented at low cost and may therefore contribute to reducing inequities. |
| ECONOMIC CONSIDERATIONS | |
| The systematic review did not address economic considerations. |
Scaling up of many of the interventions will require resources. Some community-based interventions may require fewer resources (see above) and may therefore be more appropriate in settings where resources are very constrained. Local costings should be undertaken to inform decisions on implementation. |
| MONITORING & EVALUATION | |
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Larger and more rigorous comparative studies are required to determine the effects and the cost-effectiveness of the community-based dengue control strategies. Future studies should provide details of the interventions used and describe the contexts in which they were delivered. Attention needs to be paid to the sustainability of dengue vector control strategies over time. |
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*Judgements made by the authors of this summary, not necessarily those of the review authors, based on the findings of the review and consultation with researchers and policymakers in low-income countries. For additional details about how these judgements were made see: www.supportsummaries.org/methods |
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Al-Muhandis N, Hunter PR. The value of educational messages embedded in a community-based approach to combat dengue Fever: a systematic review and meta regression analysis. PLoS Negl Trop Dis. 2011;5(8):e1278.
Bowman LR, Donegan S, McCall PJ. Is Dengue Vector Control Deficient in Effectiveness or Evidence?: Systematic Review and Meta-analysis. PLoS Negl Trop Dis. 2016;10(3):e0004551.
Erlanger TE, Keiser J, Utzinger J. Effect of dengue vector control interventions on entomological parameters in developing countries: a systematic review and meta-analysis. Medical and veterinary entomology. 2008;22(3):203-221.
Horstick O, Runge-Ranzinger S, Nathan MB, Kroeger A. Dengue vector-control services: how do they work? A systematic literature review and country case studies. Transactions of the Royal Society of Tropical Medicine and Hygiene. 2010; 104(6):379-386.
Agustín Ciapponi, Instituto de Efectividad Clínica y Sanitaria, Buenos Aires, Argentina.
None declared. For details, see: www.supportsummaries.org/coi
This summary has been peer reviewed by: David Sinclair and Christopher Heintze.
Heintze C, Velasco Garrido M, Kroeger A. What do community-based dengue control programmes achieve? A systematic review of published evaluations. Transactions of the Royal Society of Tropical Medicine and Hygiene. 2007;101(4):317-325.
Keywords
evidence-informed health policy, evidence-based, systematic review, health systems research, health care, low and middle-income countries, developing countries, primary health care, dengue, Aedes, control, vector control, community-based programmes
