Dengue care in an emergency service during 2023 and 2024

Background. In 2024, Argentina faced the worst dengue outbreak in its history within a context marked by high healthcarecosts and resource scarcity. Although regulations allowed for case confirmation through epidemiological linkage withoutconfirmatory tests, its application was inconsistent across different settings. Objective. To describe the characteristics, resource usage, and clinical outcomes of patients with suspected dengue attended during the first quarter of 2024, comparing data with the same period in 2023. Methods. A retrospective observational study, using secondary data obtained from electronic medical records from a pri-vate university hospital in Buenos Aires, Argentina. Emergency department consultations of adult patients with suspected dengue fever were identified from the Mandatory Notification Form of the National Health Surveillance System. At an institu-tional level, during the 2024 outbreak, confirmation via epidemiological linkage was enabled without requiring confirmatorytests. Meanwhile, laboratory testing was restricted to patients with warning signs, risk factors, or severe cases. Results. In 2023, 186 patients with suspected dengue were detected; in 2024, this number increased to 1,617. Themajority were young adults, with an increase in the clinical presentation of headache, retro-orbital pain, and nausea/vo-miting. Confirmed cases increased from 111 to 443. Laboratory tests performed within 30 days decreased from 82.79 %to 49.65 %. During 2024, 652/1,617 patients (40.32 %) received a diagnostic method for dengue confirmation. Follow-upvisits decreased at 2 and 7 days (p=0.01). No hospitalizations or deaths due to dengue were recorded. Conclusions. This study showed a significant increase in dengue cases at an emergency department during the 2024 outbreak. Despite the scarcity of resources and the reduction in serological testing, healthcare was appropriately adjustedto the emergency situation, with no increase in adverse outcomes such as hospitalizations or deaths. (AU)