Lessons learnt on scaling-up measures to reduce dengue mosquito densities

TDR news item
1 November 2017

Lessons learnt on TDR-supported studies scaling up interventions to reduce mosquito densities have been published. The studies examine the different types of scaling up possible, and provide examples from each of the 4 countries involved: Brazil, Colombia, Mexico and Uruguay.

Antonio Lima with government dengue tracking system
Antonio Lima with government dengue tracking system

The research was designed to examine options to reduce the density of the dengue-transmitting mosquito vector Aedes aegypti. People in these settings often leave containers outside that are ideal breeding sites for the mosquito. Little attention had been paid to studying which ones were the most productive, and these studies examined that and how to reduce their numbers through community-based approaches to designing and installing screens and reducing the numbers of containers.

The paper puts into perspective the 3 types of scaling and 5 levels of issues to consider:

  • Political: Financial, human resources and/or administrative support provided by ministries of health or other sectors
  • Vector control: Support by vector control services and staff
  • Administrative: Regulations for involving industry in the process; management issues, project activities definition, field team and local enterprises
  • Supply: Availability and acquisition of materials
  • Acceptance: Acceptance of those involved and/or served

Lessons learnt

Coordination with different sectors was found to be a key element. The authors explain that extended interventions require input and leadership from multiple sectors, particularly from ministries of health, and from environment and social protection.

Market place in Yucatan, Mexico.

Engaging community members as staff or local suppliers reduced costs and strengthened ownership in Uruguay and Colombia.

The larger groups often require different approaches to address the varied socio-economic conditions, and the study found targeted communication strategies can avoid misunderstandings or lack of information.

Political will was found to be crucial, and in these studies that was challenged with changes of government and sometimes unclear decision-making power in a decentralised administrative system. In addition, the chikungunya and Zika outbreaks moved resources into other directions. The authors provide a list of barriers that should be considered in scaling up projects.

For more information, contact:
Dr Piero Olliaro
E-mail: olliarop@who.int.

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