The Hawai‘i Department of Health (DOH) has confirmed a new travel-related dengue virus case on Oʻahu. This brings the total number of dengue cases in the state to five in 2025, with one on Maui and four on Oʻahu. The individual contracted the virus while traveling in a region where dengue is prevalent, according to the DOH.
DOH teams have been dispatched to implement mosquito control measures in the affected area. They are also conducting inspections. The public is advised to follow recommended practices to prevent local transmission.
"Dengue virus is transmitted from an infected person to a mosquito, and then to another person," explained the DOH. Although Hawai‘i hosts mosquitoes capable of carrying dengue, the disease is not endemic to the state and remains largely associated with travelers. Globally, several regions are experiencing heightened dengue activity.
Outbreaks occur in various parts of the world, including Central and South America, Asia (including the Republic of the Philippines), the Middle East, Africa, and several Pacific Islands, like American Samoa, the Federated States of Micronesia, the Republic of the Marshall Islands, and the Republic of Palau. Popular Caribbean tourist destinations such as Puerto Rico are also affected.
In 2024, 16 travel-related dengue cases were reported in Hawai‘i. Affected travelers had been to countries where dengue is endemic, including Brazil, Argentina, Costa Rica, and El Salvador, among others. The Centers for Disease Control and Prevention (CDC) advises travelers to these areas to use insect repellent, wear protective clothing, and sleep in protected environments to prevent mosquito bites. Increased dengue cases have been reported in some countries, so travelers should seek updated travel advice four to six weeks before their trip.
Travelers returning from areas with dengue risk should take precautions to avoid mosquito bites for three weeks. Those showing symptoms within two weeks of returning should seek medical assessment. Symptoms include fever, nausea, vomiting, rash, and body aches and can last two to seven days. Severe cases can occur, but most recover within a week.
In dengue outbreak areas, the DOH’s Vector Control Branch conducts mosquito-reduction activities to minimize transmission. Even in areas without reported cases, reducing mosquito breeding sites is recommended as a preventive measure.
Mosquitoes breed in small amounts of standing water found in items like buckets, planters, and rain barrels. Eliminating these water sources can help control mosquito populations.