culex larvae

Challenge: Public Health

Public health, as related to vector-borne diseases (VBD)

According to the World Health Organization (WHO), vector-borne diseases (VBD) are responsible for 17 percent of all infectious diseases and annually cause more than a million human deaths. More than half of the world’s population is at risk. Through a combination of rising healthcare costs, lost wages and earning potential, companion care costs, impacts on livestock and companion animals, and other factors, the economic burden of VBDs is staggering. Malaria alone carries an economic burden of an estimated $12 billion annually in Africa. Viewed from a global scope, the annual economic impact of all VBDs is incalculably enormous.

The vectors include mosquitoes (principally Aedes, Anopheles, and Culex species), sandflies, black flies, tsetse flies, triatomine bugs, ticks, fleas, and others. Of these, mosquitoes alone are now widely known as the world’s most dangerous animal, killing an estimated 725,000 people per year.

Some of the most problematic vectors have been managed successfully in the past. For example, in the first half of the 20th century, Aedes aegypti was widespread throughout much of South and Central America, but a sustained and coordinated regional effort reduced its incidence to manageable levels. As mosquito levels decreased, other political pressures intervened, and the effort was largely abandoned. Now, over half a century later, the same species is once again widespread in the region and responsible for the Zika, dengue, yellow fever, and chikungunya crises.

Critical Needs:

The challenge of VBDs is multifaceted, with no single or simple solution in sight. Intuitively, it seems that there should be a strong correlation between controlling the arthropod vectors of disease and reducing the negative consequences of disease transmission, but this does not always prove to be true. Challenge areas include:

  • Research: From resistance and monitoring/surveillance issues to evaluating the effectiveness of a vast array of control and management tools, effort is needed to evaluate the current tools and practices used in vector control.
  • Innovation: Development of new scientific solutions will be needed in the coming decades to address this rapidly changing problem. A nimble scientific and vector control community must be prepared to devise, fund, develop, and deploy measures in ways we don’t yet envision.
  • Implementation: Battling vectors is not a new endeavor. Established protocols exist to survey, monitor, and control pests, and an increasingly broad suite of tools are now at our disposal. A challenge is in developing a sustained response that lasts for decades and covers vast territories. The scope and scale of implementation of past efforts have been insufficient for the challenge.
  • Training: From training pesticide applicators in under-developed regions to recruiting and training more medical entomologists and academic researchers, an educated and skilled workforce is essential to combat VBDs.
  • Influence: The funding landscape for the scientific community is changing rapidly with the development of new opportunities, while a challenging federal-funding environment demonstrates the need for effective advocacy efforts.
  • Communication: We live in an age when misinformation seemingly spreads faster than scientific information. A challenge faced by the scientific community is ensuring that those affected by VBDs are presented with sufficient knowledge and the tools to protect themselves and their families.
  • Coordination: The world today is more connected than ever before with global travel and trade on the rise, facilitating the spread of disease vectors. As such, efforts cannot be confined to geopolitical borders. Development of a combined regional or international effort may be required.
  • Collaborative models: This coordinated response will require the development of collaborative models that bring together a wide variety of stakeholders.