The first instance of locally transmitted dengue fever in Virginia has been confirmed in a resident of Fairfax and Loudoun counties, west of Washington D.C. The patient had not recently traveled outside the state but had close contact with another individual diagnosed with dengue fever after international travel several weeks prior.
Health officials suspect that a local mosquito bit the infected traveler and subsequently the new patient, leading to the spread of the virus within the community. Dengue fever is transmitted through mosquito bites and not directly from person to person. Officials stated there is currently no evidence of ongoing transmission in Virginia, and the risk of contracting the illness in the state remains low.
This case follows closely behind the first locally acquired dengue fever case recorded this year in Florida. Virginia becomes the ninth U.S. state to report local dengue transmission since 2010, according to CDC data. Since 2010, over 600 cases of locally spreading dengue have been documented nationwide.
Florida has reported the highest number of these cases, exceeding 600, followed by Hawaii with 250, Texas with 47, and California with 27. Other states with reported local transmission include Arizona, North Carolina, West Virginia, and New York.
Dengue fever is caused by a virus spread by infected Aedes species mosquitoes, known for the white bands on their legs. Symptoms typically appear five to seven days after a mosquito bite and can include fever, severe headache, pain behind the eyes, muscle and joint aches, nausea, vomiting, and a rash. While most individuals recover within a week, severe cases can lead to shock, internal bleeding, and potentially death if not treated promptly.
The Centers for Disease Control and Prevention (CDC) has updated its travel alerts for dengue, noting unusual upticks in cases globally. The agency has warned travelers heading to 11 countries and territories—Bolivia, Cambodia, Colombia, Kenya, Malaysia, Maldives, New Caledonia, Samoa, Sri Lanka, Tonga, and Vietnam—to take precautions due to a rise in dengue cases in these regions.
Dengue fever was nearly eradicated in the U.S. in the 1970s following a campaign to eliminate the Aedes aegypti mosquito. However, after the campaign's discontinuation, the mosquito and the virus have resurfaced, leading to sporadic outbreaks, particularly in Florida, Texas, and California.
Health officials advise travelers to use insect repellent, wear long-sleeved shirts and long pants when outdoors, and sleep in screened or air-conditioned rooms. Children under five, adults over 65, and pregnant women are considered at higher risk for severe illness. Most dengue fever cases recorded in the U.S. are associated with international travel.