Phylogenetic Investigations of Dengue 2019–2021 Outbreak in Guadeloupe and Martinique Caribbean Islands

Abstract

Dengue fever has been a public health problem in the Caribbean region since 1981, when it first reappeared in Cuba. In 1989, it was reported in Martinique and Guadeloupe (two French islands 200 km apart); since then, DENV has caused several epidemics locally. In 2019–2021, DENV-1, DENV-2, and DENV-3 were detected. Serotype distribution was differentiated, with DENV-2 and DENV-3 predominating in Guadeloupe and Martinique, respectively. Complete genome sequencing was carried out on 32 specimens, and phylogenic analysis identified the circulation of genotype V for DENV-1, cosmopolitan genotype for DENV-2, and genotype III for DENV-3. However, two distinct circulating groups were identified for DENV-1 and DENV-3, suggesting independent introductions. Overall, despite the context of the COVID-19 pandemic and the associated travel restrictions, these results confirm the active circulation of DENV and specific epidemiological features on each of the two islands. Such differences may be linked to the founder effect of the various introduction events, and to local factors such as the population immunity and the transmission capacity of the vectors. Further genomic and epidemiological characterization of DENV strains remains essential to understand how dengue spreads in each specific geographical context and to prevent future epidemics.

Molecular epidemiology identifies the expansion of the DENV2 epidemic lineage from the French Caribbean Islands to French Guiana and mainland France, 2023 to 2024

“…Dengue is endemo-epidemic in the French Caribbean Islands where it has caused several epidemics over the past decades including in 2013-2014 and in 2019-2021, during which distinct serotypes circulated on the islands of Guadeloupe and Martinique [13,14]. In 2013-2014, DENV serotype 4 (DENV4) dominated in Guadeloupe and DENV2 was the main serotype in Martinique, while in 2019-2021, DENV2 was dominant Maximum-likelihood phylogeny of all genomes from the FCI epidemic combined with all DENV2 sequences from the cosmopolitan genotype covering more than 85% of the CDS available on GenBank up to 22 November 2023 and a set of reference sequences from other genotypes.…”