Aedes vector control and immunization against dengue in Brazil: exploring policy perceptions towards integration

Abstract

The World Health Organization has listed dengue among the 10 top global health threats. Half of the world's population is at risk of contracting the disease, estimated to cause nearly 400 million infections and more than 9 billion dollars in healthcare costs and economic losses per year. This burden of disease continues to grow and is disproportionately concentrated in the poorest areas of the globe. Currently, there are no licensed antivirals, nor a licensed vaccine indicated for use in individuals previously unexposed to dengue viruses. For many decades, dengue prevention programs have been based primarily on vector control methods, notably environmental management, community engagement, and insecticide application.

However, at this time, several new techniques are becoming available that show promise for more effective control. Emerging modalities for vector control—such as Wolbachia-based methods, genetic manipulations, and the release of sterile mosquitoes —have, in many studies, been proven to be both effective and safe, albeit some unanswered questions persist. On the vaccine front, Takeda Pharmaceuticals has released Phase III clinical data from its tetravalent dengue vaccine candidate, showing efficacy and safety regardless patients’ previous exposure to dengue viruses. The company started regulatory registration in endemic and travel markets.

As these health technologies become available, important questions must be addressed about the context in which they will be implemented. This thesis proposes an exploratory descriptive study about such a context, using implementation research as theoretical foundation. Brazil is the geographical scope for the study – the country with the highest dengue burden in the Americas.

Employing qualitative interviews with dengue policymakers as primary data source, the research assesses their views about the current vector programs, their expectation about new technologies, and barriers and enabling factors for integrating these tools into existing dengue programs.