O-66 Distribution of mosquito species in select communities of regions one, four, six, seven and nine in Guyana in 2025

Methods: Secondary data were obtained from the Ministry of Health Vector Control Services Medical Entomology 2025 species database and relative abundance, species distribution, Shannon diversity index and species richness calculated. Mosquito species were classified into relative abundance classes and distribution status and mapped using Quantum Geographic Information System v3.22.12.

Results: During routine collections from May to September 2025, 1971 mosquitoes were identified consisting of 43 species belonging to 13 genera. Regarding medically relevant mosquitoes, the most dominant species observed was the Culex portesi (n=577), despite being confined to Region Four with a sporadic distribution. This was followed by Culex quinquefasciatus (n=477) and Culex nigripalpus (n=189) both with a constant distribution. Other species identified that were of public health concern included Anopheles darlingi (Regions One and Nine) primary vector for malaria, Coquilletida venezuelensis (Regions One, Four and Six) a secondary vector for Oropouche virus, Haemagogus janthinomys (Region Four ) a primary vector for yellow fever, Aedes albopictus and Aedes aegypti (Regions One, Seven and Nine) primary vectors for arboviruses. Overall, the species richness was 43 and a Shannon diversity index of 2.34 was obtained indicating a high species diversity.

Conclusion: This study highlights the benefits and importance of mapping the distribution of mosquito species of public health significance throughout the different administrative regions in Guyana. The information gathered provides a clearer understanding of the ecological distribution and diversity of mosquito species within Guyana. Knowledge obtained from future studies will assist in better understanding of vector-borne disease transmission in Guyana, which can lead to data driven vector control policy development throughout the country