Public Health Interventions for Aedes Control in the Time of Zikavirus- A Meta-Review on Effectiveness of Vector Control Strategies.

BACKGROUND

There is renewed interest in effective measures to control Zika and dengue vectors. A synthesis of published literature with a focus on the quality of evidence is warranted to determine the effectiveness of vector control strategies.

METHODOLOGY

We conducted a meta-review assessing the effectiveness of any Aedes control measure. We searched Scopus and Medline for relevant reviews through to May 2016. Titles, abstracts and full texts were assessed independently for inclusion by two authors. Data extraction was performed in duplicate and validity of the evidence was assessed using GRADE criteria.

FINDINGS

13 systematic reviews that investigated the effect of control measures on entomological parameters or disease incidence were included. Biological controls seem to achieve better reduction of entomological indices than chemical controls, while educational campaigns can reduce breeding habitats. Integrated vector control strategies may not always increase effectiveness. The efficacy of any control programme is dependent on local settings, intervention type, resources and study duration, which may partly explain the varying degree of success between studies. Nevertheless, the quality of evidence was mostly low to very low due to poor reporting of study design, observational methodologies, heterogeneity, and indirect outcomes, thus hindering an evidence-based recommendation.

CONCLUSIONS

The evidence for the effectiveness of Aedes control measures is mixed. Chemical control, which is commonly used, does not appear to be associated with sustainable reductions of mosquito populations over time. Indeed, by contributing to a false sense of security, chemical control may reduce the effectiveness of educational interventions aimed at encouraging local people to remove mosquito breeding sites. Better quality studies of the impact of vector control interventions on the incidence of human infections with Dengue or Zika are still needed.