Ingrid Chen, PhD, has received a $900,000 grant from the Armed Forces Pest Management Board Deployed Warfighter Protection Program to develop second-generation passive emanators to reduce mosquito-biting behavior.

Mosquito-borne diseases are collectively responsible for hundreds of thousands of deaths annually and are rapidly increasing in incidence due to climate change and unplanned urbanization. New interventions are needed to provide adequate protection for mobile populations and those in endemic settings, particularly for use outdoors.

Passive emanators, also known as spatial repellent devices, are portable light-weight products that are hung up or placed on the ground indoors or outdoors to diffuse volatile chemicals, creating a protective space from mosquito bites in their vicinity through multiple mosquito behavioral responses collectively known as spatial repellency. This product class is currently being evaluated for product prequalification by the World Health Organization for public health use. It is expected to be available in the next one to two years.

However, all products in development use volatile pyrethroid-class chemicals as active ingredients, placing significant pressure on insecticide resistance. Chen’s project seeks to accelerate the development of second-generation passive emanators with novel active ingredients through entomological testing of promising volatile compounds, the development of slow-release formulations, and the creation of a product prototype that offers full-body protection for mobile populations.