O-62 Molecular surveillance of the invasive Aedes vittatus in Jamaica

Methods: Adult and immature Aedes vittatus specimens were collected using convenient sampling approach from the parishes of Westmoreland, St. Elizabeth, St. Ann, Kingston and St. Andrew between 2023 and 2024, in the wet and dry seasons. DNA was extracted from adult specimens and the mitochondrial gene cytochrome c oxidase subunit I (COI) was amplified using the primers LCO1490 (5’-GGTCAACAAATCATAAAGATATTGG-3’) and HCO2198 (5’-TAAACTTCAGGGTGACCAAAAAATCA-3’) followed by Sanger sequencing. Consensus Ae. vittatus COI sequences were generated and aligned with Ae. vittatus COI sequences available on the GenBank database using the Molecular Evolutionary Genetics Analysis (MEGA) software v11. Using DnaSP v6, unique haplotypes were identified and inferred using a TCS statistical parsimony network implemented in PopART.

Results: Molecular analysis confirmed the presence of Ae. vittatus in four parishes, with distinct spatial clustering in peri-urban and rural settings. The alignment of a 494bp fragment of eleven COI sequences from the Jamaican Ae. vittatus specimens revealed nine unique haplotypes. This highlights the high genetic diversity present amongst the Jamaican samples. A wider genetic scope using the deposited COI fragment of Ae. vittatus specimens from GenBank revealed multiple introductions into the country from the Indian subcontinent. Analysis of the haplotype relationships highlights that the Jamaican sequences fell within three main clusters and were genetically similar to sequences from Cuba, Dominican Republic, Pakistan, India, Nepal and Sri Lanka. Furthermore, the West Road and St. Elizabeth specimens showed multiple single nucleotide polymorphisms.

Conclusion: This study highlights the value of molecular surveillance in enhancing vector awareness in Jamaica. Phylogeographic surveillance can help understand patterns of invasion or movement of vector populations. This knowledge shapes the foundation for which effective and targeted vector strategies can be implemented to strengthen preparedness and informed data-driven control measures in the Caribbean.