Snap-shot assessment of adult mosquito (Diptera: Culicidae) densities on the Turks and Caicos Islands, February 2022

Abstract

In many of the small island communities of the Caribbean, much of the vector surveillance effort is focused on house-to-house peri-focal surveys to collect data on larval indices. Adult mosquito trapping is not always routine or affordable and is usually focused on ad hoc biting issues or small-scale investigations. This makes understanding the relative importance and densities of the common urban mosquitoes, such as Aedes aegypti and Culex quinquefasciatus, problematic. This snap-shot survey in February 2022 using BG-Sentinel traps at 30 different locations across five islands of the Turks and Caicos, aimed to provide the first island-wide assessment of urban mosquito densities. In total, 2,820 adult mosquitoes were collected over 285 trap nights. Aedes aegypti was most common on the island of Providenciales, with very low densities recorded on South Caicos, North and Middle Caicos, with Ae. aegypti most highly abundant in the main commercial centres. The highest densities of Cx. quinquefasciatus were trapped on North Caicos. Small numbers of other species were also collected, including the first record of Anopheles in TCI. This established framework of trapping and initial assessment provides a platform for continued monitoring of mosquitoes in TCI to better inform mosquito-borne disease risk assessment and future vector control efforts.

Dr Sara Gandy

Research Associate

My research primarily focuses on understanding the ecological drivers of tick-borne diseases to provide insights on the mechanisms involved in transmission cycles, especially on the interactions between ticks, hosts and pathogens. My research includes investigating the impacts of environmental changes (woodland restoration, rewilding) and host community composition (deer, rodent and birds) on tick-borne diseases risks in the UK. Some of my findings uncovered an opposing effect of deer densities on Lyme disease hazard through their positive effects on tick density and negative effects on infection prevalence. I also published work looking at spatiotemporal changes in tick distribution using passive surveillance data and I have been leading the National Tick Survey, which involves collaborating with stakeholders in thirty National Parks and recreational areas to collect ticks and test them for various tick-transmitted pathogens between 2021 and 2024. The goal is to understand disease hazard and temporal variation in areas visited by members of the public and deliver tick awareness messages.