Barbados is poised to become the next site for cutting-edge mosquito-borne disease control research, as scientists from The University of the West Indies (UWI) Cave Hill’s Centre for Biosecurity Studies move forward with plans to test a locally developed lethal ovitrap and evaluate a globally successful biological control method that has drastically cut dengue rates abroad.
For years, Caribbean nations like Barbados have relied heavily on chemical insecticides to curb populations of disease-carrying mosquitoes, particularly Aedes aegypti and Aedes albopictus – the primary vectors for dangerous illnesses including dengue, chikungunya, yellow fever and Zika. Growing concerns over chemical resistance and environmental impacts have pushed researchers to pursue sustainable, targeted alternatives, and two promising options are now moving toward local assessment.
The first tool under development at UWI is the lethal ovitrap, a purpose-built trap designed to mimic the small, dark water-filled breeding grounds that container-breeding Aedes mosquitoes prefer. The design is deceptively simple: a dark water-holding container fitted with a fine mesh screen positioned below an egg-laying surface. When female mosquitoes enter the trap to lay eggs, the eggs drop through the mesh into the water below. Larvae hatch and develop, but any emerging adult mosquitoes become trapped beneath the mesh and cannot escape to continue spreading disease. Centre director Dr. Kirk Douglas calls the device a mass adult mosquito removal tool that expands the existing vector control toolkit and reduces dependence on chemical interventions.
“It’s an innovation we have started at the Centre for Biosecurity Studies at UWI Cave Hill,” Douglas explained in an interview with Barbados TODAY. “We are hoping to launch a formal field trial soon, where we will monitor treatment areas to measure how these mass removal devices reduce transmission of not just dengue, but a range of other vector-borne diseases.”
Alongside the ovitrap project, the centre is closely tracking the global performance of Wolbachia pipientis, a naturally occurring endosymbiotic bacteria that has emerged as a leading biological control alternative. The bacteria, which lives naturally inside the cells of many insect species, works by blocking viral replication inside mosquito bodies, preventing them from spreading dangerous diseases to humans.
Wolbachia-based control relies on two core mechanisms. When male mosquitoes carrying the bacteria are released into wild populations and mate with uninfected wild females, the resulting eggs do not develop due to cytoplasmic incompatibility, gradually reducing overall mosquito populations. In the population replacement strategy, both male and female Wolbachia-carrying mosquitoes are released, establishing a bacteria-carrying local mosquito population that cannot transmit viral diseases. The approach has already delivered dramatic results in large-scale international trials, with an Indonesian cluster randomized trial recording a 77% drop in confirmed symptomatic dengue cases and an 86% reduction in dengue-related hospitalizations compared to untreated control areas.
Initial skepticism about the method’s scalability and real-world effectiveness has largely been laid to rest by growing empirical evidence, Douglas noted. Currently, the United States is conducting final evaluations ahead of rolling out Wolbachia releases in warm, high-risk states including California and Florida, where mosquito-borne disease outbreaks are a recurring public health threat.
For Barbados, where dengue outbreaks regularly strain public health resources, the method offers a long-term, sustainable way to manage vector populations at the source. “When you target the mosquito itself through biological control, you prevent new infections at the root, which makes outbreak management far more effective,” Douglas said. The UWI centre will continue monitoring global research and trial results to assess whether the Wolbachia method is a viable strategy for Barbados, alongside advancing the upcoming lethal ovitrap field trials. As public health officials around the world grapple with rising mosquito-borne disease cases linked to climate change, the research in Barbados could offer a model for other small island nations facing similar vector control challenges.