Dengue is a viral disease transmitted to humans by infected mosquitoes being Aedes aegypti the primary vector. Belonging to the species Orthoflavivirus denguei, Flaviviridae family, and Orthoflavivirus genus, dengue virus (DENV) is a small, enveloped virus with a positive sense single-stranded RNA genome and subdivided into four serotypes phylogenetically and antigenically distinct (DENV-1, DENV-2, DENV-3, and DENV-4) [1,2]. The clinical presentation of the disease may vary in severity and infection can range from an asymptomatic disease to a mild febrile prodrome to more serious clinical conditions such severe dengue [2,3,4,5].

The global incidence of DENV has been growing rapidly in recent years, consequently, there was a significant increase in notifications in areas where positive cases had historically very low levels. Rio Grande do Sul (RS) state in the south of Brazil presents data with remarkable differences compared to previous periods since the rate of new municipalities with DENV transmission jumped from 1-2/year to 10 in 2022 [6]. In RS state in 2022, there was a 286.6% increase in the number of confirmed cases in this last year, accounting for more than 67 thousand confirmed cases, 66 patients died, and 91% of the municipalities infested by A. aegypti [7].

Therefore, the main objective of this study was to characterize and monitor the DENV genetic diversity during an outbreak in the year 2022 in the state of RS, Brazil, tracking serotypes, genotypes, and strains through high-performance sequencing. In addition, we intend to generate more accurate and agile data to understand viral transmission patterns, promote the management of outbreaks, and provide information that serves as a subsidy for developing strategies to control viral dissemination and protect public health.