Increase in Travel-Associated and Locally Acquired Dengue Cases — United States, 2024

Dengue is a mosquitoborne viral disease that can cause mild to severe illness and death. During 2010-2023, an average of 828 dengue cases (range = 202-2,055) were reported annually to ArboNET, the national arboviral surveillance system for the 50 U.S. states and the District of Columbia. During 2024, a record 3,798 dengue cases were reported, representing a 359% increase above the 2010-2023 annual average. Among these 3,798 cases, 97.2% were associated with travel outside the reporting jurisdiction during the 2 weeks preceding symptom onset; the remaining 2.8% were locally acquired. The number of dengue cases peaked during July-September (accounting for 41.6% of total annual cases), with the highest percentage (21.8%) of cases occurring among persons aged 50-59 years. Among travel-associated cases, acquisition occurred primarily in the Caribbean (including Puerto Rico and the U.S. Virgin Islands) (34.1%), North America (Mexico and the United States) (24.3%), and Central America (15.6%); Hispanic or Latino persons accounted for 57.5% of all cases. Among all patients, 36.1% required hospitalization, 2.8% of cases were severe, and six (0.2%) patients died. Among 1,204 patients with known dengue virus (DENV) serotype, DENV-3 was the most commonly reported (54.8%) among the four DENV serotypes. These findings underscore the urgent need for enhanced prevention strategies, clinical awareness, and tailored public health messaging for travelers to areas where dengue is endemic.