Whole Genome Sequencing of DENV-2 isolated from Aedes aegypti mosquitoes in Esmeraldas, Ecuador. Genomic epidemiology of genotype III Southern Asian-American in the country.

Carrazco-Montalvo, A.; Gutierrez-Pallo, D.; Arevalo, V.; Ponce, P.; Rodriguez-Polit, C.; Alarcon, D.; Echeverria-Garces, G.; Coloma, J.; Nipaz, V.; Cevallos, V.

doi:10.1101/2024.02.06.579255

bioRxiv · 10.1101/2024.02.06.579255

Whole Genome Sequencing of DENV-2 isolated from Aedes aegypti mosquitoes in Esmeraldas, Ecuador. Genomic epidemiology of genotype III Southern Asian-American in the country.

Carrazco-Montalvo, A.·Gutierrez-Pallo, D.·Arevalo, V.·Ponce, P.·Rodriguez-Polit, C.·Alarcon, D.·Echeverria-Garces, G.·Coloma, J.·Nipaz, V.·Cevallos, V.

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Abstract

Ecuador is a tropical country reporting Dengue virus (DENV) outbreaks with areas of hyperendemic viral transmission. Entomo-virological surveillance and monitoring effort conducted in the Northwestern border province of Esmeraldas in April 2022, five pools of female Aedes aegypti mosquitoes from a rural community tested positive for DENV serotype 2 by RT-qPCR. One pool was sequenced by Illumina MiSeq, and it corresponded to genotype III Southern Asian-American. Comparison with other genomes revealed genetic similarity to a human DENV genome sequenced in 2021, also from Esmeraldas. Potential introduction events to the country could have originated from Colombia, considering the vicinity of the collection sites to the neighboring country and high human movement. The inclusion of genomic information complements entomo-virological surveillance, providing valuable insights into genetic variants. This contribution enhances our understanding of Dengue virus (DENV) epidemiology in rural areas and guides evidence-based decisions for surveillance and interventions. Author SummaryIn this study, the complete genetic information of the dengue virus isolated from the mosquito vector Aedes aegypti was characterized using molecular biology, sequencing, and bioinformatics analysis. The isolation of the virus from the vector has contributed significantly to our understanding of the transmission dynamics of the disease and its genetic relationship with human cases. Identifying the serotypes and genotypes circulating in Ecuador has enabled us to comprehend the evolution of the virus from 2014 to 2023. Therefore, surveillance of genetic variability would aid in adapting precise prevention and control strategies to the genetic variants present in a specific geographical area. Entomo-virological surveillance is essential for assessing changes in risk and the impact of control measures.

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Carrazco-Montalvo, A., Gutierrez-Pallo, D., Arevalo, V., Ponce, P., Rodriguez-Polit, C., Alarcon, D., Echeverria-Garces, G., Coloma, J., Nipaz, V., Cevallos, V.. 2024-02-08. Whole Genome Sequencing of DENV-2 isolated from Aedes aegypti mosquitoes in Esmeraldas, Ecuador. Genomic epidemiology of genotype III Southern Asian-American in the country.. https://doi.org/10.1101/2024.02.06.579255

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