As spring break approaches, U.S. health officials are raising concerns about the spread of dengue fever, a mosquito-borne virus surging in popular travel hotspots. According to the Centers for Disease Control and Prevention (CDC), over 1,000 cases have already been reported in the U.S. this year, with nearly 4,000 travel-related infections in 2024 alone.

The virus is particularly active in Puerto Rico, the U.S. Virgin Islands, and Mexico, which has already seen 20,000 cases in 2025. Dengue fever can cause severe symptoms, including fever, eye pain, bleeding from the nose and gums, and dehydration. Without treatment, the disease can be fatal in up to 20% of cases.

The CDC has issued urgent travel guidance, especially for spring and summer months when mosquito activity is highest. They urge travelers to take precautions such as:

• Wearing long sleeves and pants
• Using EPA-approved mosquito repellent
• Staying in air-conditioned or screened accommodations
• Seeking medical attention if fever or symptoms develop

There is no specific medication to cure dengue, so prevention is key. With Aedes mosquitoes already present in parts of the U.S., officials warn that travel-associated infections could lead to small outbreaks at home.

What This Means for Los Angeles County

As global travel increases and warmer temperatures extend mosquito seasons, local transmission in places like Los Angeles becomes more possible. Local mosquito abatement districts are urging residents to take preventive action—especially when returning from travel—by reporting symptoms early and avoiding mosquito exposure.