New travel-related dengue virus case reported on Oʻahu

The Hawai‘i Department of Health has identified a new travel-related dengue virus case on Oʻahu, bringing the total number of dengue cases in the state to six for 2026.

The virus exposure came while the affected individual was traveling in a region where dengue is common. Health Department teams are conducting inspections and implementing mosquito control measures. The affected area on Oʻahu was not specified.

Health officials said that, due to specifics of this case, the expected risk of transmission is low. However, the case serves as a cautionary reminder for residents to reduce mosquito-breeding areas in standing water as much as possible.

Mosquitoes need only small amounts of standing water to breed. Common breeding sites include buckets, water-catching plants (such as bromeliads), small containers, planters, rain barrels and even cups left outside. Prevent standing water from collecting around the home and workplace by pouring out containers to prevent mosquitoes from laying eggs. More information on mosquito control can be found here.

Dengue virus is transmitted from an infected person to a mosquito and then to another person. While Hawai‘i is home to the mosquitoes that can carry dengue, the disease is not established in the state and cases are currently limited to travelers.

Dengue is a year-round risk in the tropical and subtropical areas of Central and South America (including Brazil and Mexico), Asia (including 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. Many popular tourist destinations in the Caribbean, including Puerto Rico, are also affected.

Some countries are reporting higher-than-usual numbers of dengue cases, including Samoa, Vietnam, Colombia, Cambodia, Maldives, Mali, New Caledonia, Timor-Leste, Bolivia and Guyana. Travelers should review up-to-date, country-specific travel information for guidance on dengue risk and prevention measures at least four to six weeks before traveling.

Anyone who plans to travel to or has recently visited an area with dengue risk is vulnerable to infection. The Centers for Disease Control and Prevention advises travelers to take standard precautions when visiting such areas. This includes using an Environmental Protection Agency (EPA)-registered insect repellent, wearing long-sleeved shirts and long pants outdoors and sleeping in air-conditioned rooms, rooms with window screens, or under insecticide-treated bed nets.

Travelers returning from dengue-endemic areas should take precautions to prevent mosquito bites for three weeks. If dengue symptoms develop within two weeks of return, travelers should seek medical evaluation.

Symptoms of dengue can range from mild to severe and include fever, nausea, vomiting, rash and body aches. Symptoms typically last two to seven days and while severe illness can occur, most people recover within a week. Individuals who have recently traveled and are experiencing these symptoms should contact their healthcare provider. Healthcare providers and individuals who suspect a dengue infection are advised to call the Disease Reporting Line at 808-586-4586.

In areas with suspected or confirmed dengue cases, Health Department personnel from the Vector Control Branch conduct inspections and mosquito-reduction activities. Reducing mosquito populations lowers the risk of dengue transmission to others. In areas without reported dengue cases, eliminating mosquito breeding sites around the home is a helpful preventive measure.