HONOLULU (KHON2) — The Hawai‘i Department of Health (DOH) has confirmed seven travel-related cases of dengue virus so far in 2025.
One case was reported on Maui and six on Oʻahu. These cases came from travelers who were infected while visiting places where dengue is common.
Right now, dengue is not spreading locally in Hawaiʻi, but the mosquitoes that can carry the virus are here which means the risk of local transmission is real.
Health officials are monitoring affected areas and working to prevent mosquitoes from spreading the virus further.
So, KHON2.com did a bit of digging to figure out how to protect yourself and how to recognize the signs that you may have contracted it.
1. What dengue fever actually is
Dengue (pronounced DEN-gay) is a virus spread to humans by mosquito bites. You can’t catch it from another person like a cold because it takes a mosquito to carry it from one infected person to another.
The mosquitoes that spread dengue, like Aedes aegypti and Aedes albopictus, are common in tropical and subtropical places, including parts of Hawaiʻi.
Dengue has been called “breakbone fever” because it causes strong pain in muscles and joints. While many people recover in about a week, some can get very sick and even die from severe dengue.
2. Dengue symptoms: What to watch for
If you’ve recently traveled to a country with dengue or if you live with someone who has, it’s important to know what dengue looks like. Symptoms can show up 4 to 10 days after a mosquito bite, and they often include:
- High fever (up to 104°F).
- Headache and pain behind the eyes.
- Nausea or vomiting.
- Muscle and joint pain.
- Skin rash.
- Swollen glands.
These symptoms usually last 2 to 7 days. But in some cases, dengue can get worse after the fever goes away. That’s when people need to watch for severe dengue.
3. Severe dengue is dangerous and can be deadly
Severe dengue happens in a small number of cases but can lead to bleeding, organ damage and even death. It usually shows up after the person starts feeling better, which makes it tricky.
Signs of severe dengue include:
- Stomach pain that won’t go away.
- Constant vomiting.
- Bleeding gums or nose.
- Blood in vomit or poop.
- Cold, pale skin.
- Feeling weak or restless.
- Trouble breathing.
If you or someone you know has these symptoms after a fever, get medical help right away.
4. Dengue is a global problem, and it’s growing
More than half the world’s population is at risk of dengue. According to the World Health Organization (WHO), between 100 and 400 million infections happen every year.
Some countries are seeing more dengue than ever before. Places like Fiji, the Philippines, Mexico, Tonga and Brazil have recently experienced cases.
In 2023, more than 6.5 million cases and more than 7,300 deaths were reported globally. Warmer temperatures, climate change and urban growth are helping mosquitoes spread into new places.
5. There’s no cure, but there is treatment
There’s no specific medicine to cure dengue, but most people can recover at home. Rest and fluids are the most important. Acetaminophen (like Tylenol) can help with pain and fever. Avoid ibuprofen and aspirin because they can make bleeding worse.
If symptoms get severe, hospital care may be needed. The good news? With early care, most people recover completely.
6. Stopping dengue starts with mosquito control
The only way to stop dengue is by stopping mosquitoes. In areas where cases are found, Hawai‘i’s DOH sends out Vector Control teams to look for standing water and reduce mosquito breeding.
Mosquitoes lay eggs in even small amounts of water, like in buckets, rain barrels or plants like bromeliads. To help protect yourself and your community:
- Dump standing water at least once a week.
- Clean and cover water containers.
- Use screens on windows and doors.
- Wear long sleeves and pants.
- Use EPA-registered repellents.
Mosquitoes that spread dengue bite during the day; so, protection is needed even when the sun is out.
7. Returning travelers: Don’t bring dengue back with you
If you travel to areas where dengue is common, take steps to avoid mosquito bites. This includes wearing long clothes, using repellent and staying in rooms with screens or air conditioning.
Some countries currently seeing a rise in dengue include:
- The Republic of the Philippines.
- French Polynesia.
- Colombia
- American Samoa.
- Tonga.
- Mexico.
After you return home, continue using mosquito repellent for three weeks, even if you feel fine. Why? Because you could still pass the virus to a mosquito; and then, that mosquito could infect someone else.
8. Can you get a dengue vaccine? Here’s what to know
Right now, only one dengue vaccine is available worldwide. It’s called Qdenga® (also known as TAK-003), and it’s made to help prevent serious illness from all four types of dengue virus. But it’s not for everyone.
WHO recommends Qdenga only for kids between 6 and 16 years old who live in places where dengue spreads a lot. This is because the vaccine works best when there’s a high chance of getting the virus.
The vaccine is given in two shots, three months apart. If you miss the second shot, don’t worry; you can get it as soon as possible.
Talk to your doctor before getting the vaccine, especially if you’re planning a trip to a high-risk area.
9. Does the vaccine fully protect you?
No. The dengue vaccine doesn’t protect everyone from getting sick. That’s why it should be part of a bigger plan that includes avoiding mosquito bites, cleaning up standing water and educating your community.
Even with a vaccine, mosquitoes can still spread other dangerous diseases like Zika, chikungunya, and yellow fever. So, protecting yourself from mosquitoes is always important, whether you haver the vaccine or not.
Bottom line: Stay informed, stay protected
Dengue is not spreading widely in Hawaiʻi right now, but it could. Protecting your family and neighborhood means learning how dengue spreads, recognizing the symptoms and getting rid of mosquitoes before they bite.
You can click here to learn more about dengue and here to learn more about the vaccines. To learn more or report a possible case, call the Hawai‘i Disease Reporting Line at 808-586-4586.
Whether you’re traveling or staying home, dengue prevention starts with you.