Background: Dengue is the most prevalent acute febrile disease with serious clinical consequences in the tropical and subtropical regions of Asia and America. In Peru, it represents a significant public health issue due to its hyperendemic nature, with serotype 2 (DENV-2) being the predominant serotype that leads to the most severe clinical manifestations of the disease. This study focuses on the molecular characterization and analysis of the intraserotypic diversity of DENV-2 circulating in the endemic region of Cajamarca. Methods: A total of 3,967 blood serum samples from patients with acute febrile illness (AFI) were analyzed between 2016 and 2022 to detect DENV and DENV-2 using real-time RT-PCR. The viral envelope (E) gene was then sequenced using the Sanger method. Finally, phylogenetic reconstruction was conducted using the maximum likelihood method. Results: A total of 32 complete...