okay, I’ve reviewed the provided text.Here’s a summary of the key findings and methods used to confirm the presence and distribution of Aedes albopictus on Saint barthélemy:
Key Findings:
Aedes albopictus was detected on Saint Barthélemy in October 2024.
Initial detection was followed by larval prospections that identified five breeding sites within a 400-metre radius of the initial site.
Later surveillance revealed 18 positive breeding sites in Lorient (665 m2 area) and 5 in Saint Jean (150 m2 area), suggesting a broader distribution.
The presence of Ae. albopictus on the island raises concerns about its potential spread to other Caribbean countries and the French Departments of the Americas due to frequent travel connections.
Methods Used for Species Identification and Characterization:
- Morphological Identification:
Initial identification was based on morphological criteria described by Darsie (1986) at both larval and adult stages.
key features observed included:
Abdominal terga with complete basal white bands.
Scutum with a medial-longitudinal white stripe.
Mesepimeron with non-separated white scales forming a V-shaped white spot.
- MALDI-TOF MS (Matrix-Assisted Laser Desorption Ionization-Time-of-Flight mass Spectrometry):
Used on two collected specimens to confirm species identity due to morphological similarities with other members of the Scutellaris group.
Heads and thoraxes were separated from the rest of the body, homogenized, and analyzed.
protein mass profiles were acquired using a Maldi Biotyper Sirius Mass Spectrometer.
Spectra were compared to databases from the Institut Pasteur of New Caledonia and the IHU Méditerranée, confirming the samples as Ae. albopictus.
A clustering analysis (MSP dendrogram) was performed to compare the Saint-Barthélemy specimen’s spectrum with those of other Ae. albopictus and related aedes species, confirming its identity.
- Cytochrome c Oxidase 1 (cox1) Gene barcoding:
The remaining body parts of the two specimens were used for DNA extraction and cox1 gene sequencing.
Primers HCO2198 and LCO1490 were used for PCR and Sanger sequencing.
Sequences were analyzed and aligned using BioEdit software.
A molecular phylogenetic tree was generated using the maximum likelihood method in MEGA software.
The cox1 sequences from the Saint-Barthélemy mosquitoes showed 100% homology with ae. albopictus sequences from Europe and the Americas.the study used a combination of morphological identification, MALDI-TOF MS, and cox1 gene barcoding to definitively confirm the presence of Aedes albopictus* on Saint Barthélemy and to assess its genetic similarity to populations from other regions.
