Virginia reports first locally acquired dengue case in Northern Virginia

Virginia health officials identified the state’s first locally acquired dengue case in a Northern Virginia resident, a finding that pushes a mosquito-borne illness more often linked to travel into a region where public health teams must now watch for local spread. Officials said there was no evidence of continued transmission and no additional locally acquired dengue cases at this time.

The Virginia Department of Health says dengue is spread by mosquito bites and is caused by any one of four closely related dengue viruses. It is transmitted when people are bitten by infected Aedes mosquitoes, including Aedes aegypti and Aedes albopictus. The agency also says mosquito-borne diseases can be acquired locally in Virginia or through travel to other places inside or outside the United States, a distinction that matters as mosquito season varies by year and by region across the state.

The case comes after federal health officials warned last year that dengue risk in the United States was increasing. The Centers for Disease Control and Prevention issued a health advisory on June 25, 2024, and later surveillance data showed a sharp rise in cases nationwide. A Johns Hopkins Public Health summary of CDC data said the agency recorded 9,255 U.S. dengue cases as of Dec. 31, 2024, including 6,076 that were locally acquired.

The broader picture is just as stark. The District of Columbia Department of Health said global dengue incidence rose from more than 500,000 cases in 2000 to 5.2 million in 2019. It also said 2023 brought a record 6.5 million dengue cases affecting more than 80 countries on every continent, while 2024 cases in the Americas were up 304% compared with the prior year to date. Those numbers show how quickly a disease once associated mainly with tropical travel can reach communities that have not historically treated it as a local threat.

Virginia’s response now depends on the systems meant to catch these cases early: clinician awareness, mosquito control, and public messaging that encourages people to avoid bites. In a June 3, 2026 clinician letter, the Virginia Department of Health was already addressing travel-associated illnesses and mosquitoes, underscoring that dengue was part of a wider set of mosquito-borne disease concerns before the Northern Virginia case was announced.