Travelers urged to take added precautions in wake of dengue virus case on O‘ahu

The Hawai‘i Department of Health has confirmed a travel-related dengue virus case in Hale‘iwa on O‘ahu.

Upon investigation, the health department found conditions that could increase the risk of transmission. Although vector control teams have responded and will continue to be active in the Hale‘iwa area, Hawai‘i Department of Health is urging the public is to take additional precautions to protect themselves from mosquito bites and to stop mosquitoes from breeding.

The area where the case was reported experiences high traffic of visitors and tourists, according to the health department. Highly dense populations of Aedes albopictus mosquitoes, which are vectors of dengue virus, were identified around the residence where the case was found and the surrounding area.

Initial vector control response resulted in a marked reduction of mosquitoes around the case residence. The health department will continue to monitor mosquito numbers in this area and take additional measures as needed. Signage will be posted to educate the public on how to protect themselves and prevent transmission.

The Hawai‘i Department of Health is asking for support in reducing the potential for the spread of dengue by transmission. Residents, visitors and businesses can take the following steps:

• Apply mosquito repellent on exposed skin, especially if outdoors. Repellent should be registered with the Environmental Protection Agency and contain 20-30% DEET. Other alternative active ingredients may include picaridin, oil of lemon eucalyptus or IR3535. To find the insect repellent that is right for you, visit the EPA’s website.
  
• Wear loose-fitting clothes (long sleeve and pants) that cover your skin.
  
• Keep mosquitoes out of your home or business by keeping doors closed or screens in good repair.
  
• Eliminate potential breeding sites by dumping out any standing water in or around your residence or business. This includes getting rid of rainwater collected in buckets, flower pots, used tires or even plants such as bromeliads.

Symptoms of dengue typically may be mild or severe and include fever, nausea, vomiting, rash and body aches. Symptoms typically last two to seven days and although severe and even life-threatening illness can occur, most people could recover after about a week. If you are experiencing any of the symptoms listed above, see your doctor or heath care provider and inform them that you were in an area where a case of dengue virus was confirmed.

Dengue virus is spread from infected person to person through the mosquito bites. While Hawai‘i is home to the type of mosquitos that can carry dengue, the disease is not established here in the state. Of the 10 dengue cases reported in Hawai‘i since Jan. 1, 2023 to present, five had traveled to Central or South America and five had traveled to Asia.

Some countries are reporting increased numbers of cases, so it is important, four to six weeks before you travel, to review country-specific travel information for the most up-to-date guidance on dengue risk and prevention measures for that country. Travelers returning from an area with risk of dengue should take steps to prevent mosquito bites for three weeks, and if symptoms of dengue develop within two weeks upon return, should seek medical evaluation.

For more information, visit the Disease Outbreak Control Division website and Vector Control Branch website.