Dengue is a viral infection spread by the bite of Aedes mosquitoes, which bite mostly during the day. It occurs in tropical and subtropical regions: Southeast Asia, Latin America, the Caribbean, Africa and the Pacific. There is no specific treatment: prevention rests first on avoiding mosquito bites, and aspirin and anti-inflammatory drugs such as ibuprofen should be avoided when you have a fever.
This guide draws on the WHO, the U.S. CDC (Yellow Book 2026 and the CDC dengue pages), the UK’s TravelHealthPro, the Institut Pasteur and Santé publique France. It does not replace medical advice. If you are traveling in the wet season, our page on visiting Bali in November covers the month’s weather.
Dengue when traveling: key points
- Transmission: bite of an infected Aedes mosquito (Aedes aegypti, and the tiger mosquito Aedes albopictus).
- The mosquitoes that spread it bite during the day (WHO); the CDC advises extra care in the early morning and late afternoon. Repellent is not just for the evening.
- Symptoms: 4 to 10 days after the bite, high fever, headache, pain behind the eyes, muscle aches, nausea, rash (WHO).
- No specific treatment: acetaminophen (paracetamol) for pain, no ibuprofen or aspirin (WHO, CDC Yellow Book).
- A second dengue infection raises the risk of severe disease.
- Vaccine: no dengue vaccine is currently recommended by the CDC for U.S. travelers; UK guidance allows Qdenga in some cases (see below).
What is dengue?
According to the Institut Pasteur, dengue is caused by an arbovirus of the Flaviviridae family, like yellow fever. There are four serotypes (DENV-1 to DENV-4). An infection protects against the serotype responsible but not the other three, so you can catch dengue several times, and later infections increase the risk of severe dengue.
The WHO estimates that about half of the world’s population is at risk. Reported cases rose from 505,430 in 2000 to 14.6 million in 2024, a record year with more than 12,000 deaths; the disease is now endemic in more than 100 countries. The Region of the Americas accounted for more than 13 million reported cases in 2024.
Transmission is through mosquitoes. The WHO and the Institut Pasteur also mention rarer transmission from a pregnant woman to her baby, through transfusion or through transplant. The disease does not spread by simple contact.
Symptoms to watch for
Most infections go unnoticed or stay mild. When symptoms appear, it is usually 4 to 10 days after infection, lasting 2 to 7 days, according to the WHO: high fever (up to 40 °C / 104 °F), severe headache, pain behind the eyes, muscle and joint pain, nausea, vomiting, swollen glands, skin rash. Most patients recover within 1 to 2 weeks, sometimes with fatigue lasting several weeks. The CDC Yellow Book (page dated 23 April 2025) gives a similar picture: symptoms 3 to 10 days after exposure, usually 5 to 7, with fever lasting 2 to 7 days.
Warning signs of severe dengue (WHO), which often appear after the fever has gone: severe abdominal pain, persistent vomiting, rapid breathing, bleeding gums or nose, blood in vomit or stool, intense fatigue, restlessness, intense thirst, pale and cold skin. They require immediate care. The CDC Yellow Book lists similar warning signs (severe abdominal pain, persistent vomiting, mucosal bleeding, lethargy or restlessness).
If you have a fever, see a doctor promptly. The WHO says acetaminophen (paracetamol) can relieve pain, while ibuprofen and aspirin may increase the risk of bleeding; the CDC Yellow Book likewise advises patients managed at home to avoid aspirin and other NSAIDs such as ibuprofen. On your return, any fever should be checked by a doctor, telling them which country you visited; where malaria also occurs, only a test can tell the two apart.
Where does dengue occur?
The CDC Yellow Book (page dated 23 April 2025) says dengue is endemic in tropical and subtropical regions in more than 100 countries and destinations, including Puerto Rico, the U.S. Virgin Islands and U.S.-affiliated Pacific Islands, with sporadic local transmission in Florida, Hawaii, Texas, Arizona (2022) and California (2023). TravelHealthPro (UK, checked 12 November 2026) lists the Caribbean, Central and South America, Africa, Asia and the Pacific Islands, notes that most UK cases are linked to travel in Asia, Central and South America and the Caribbean, and reports locally acquired cases in Croatia, France, Italy, Madeira and Spain.
Santé publique France says the virus is hyper-endemic in the French overseas departments in the Americas (Guadeloupe, Martinique, French Guiana). The WHO also reported cases in 2024 in La Réunion and Mayotte, and 308 cases reported by Spain, France and Italy. The Institut Pasteur records locally acquired cases in mainland France since 2010, as the tiger mosquito is established in many departments.
Risk changes quickly from one season and one outbreak to the next, so we do not give a country-by-country table here. Before you go, read the current notices for your destination: the CDC Travelers’ Health destination pages in the US and the TravelHealthPro dengue page and country pages in the UK. Two general points. First, season matters: outbreaks often follow the rainy season, so check the best time to go page of your destination, for example when to visit Laos. Second, cities do not protect you: unlike malaria, which is rather rural, dengue also affects capitals. The WHO notes that it occurs mainly in urban and semi-urban areas.
Protecting yourself from bites: the basis of prevention
The WHO recommends protecting yourself from bites during the day as well as in the evening to reduce the risk:
- clothing that covers as much of the body as possible;
- a repellent containing DEET, icaridin (picaridin) or IR3535 on exposed skin (the CDC advises using an EPA-registered repellent);
- a bed net, ideally treated with insecticide, if you sleep during the day (naps, jet lag);
- screens on windows (or air conditioning), mosquito coils or diffusers;
- no standing water around your accommodation: saucers, buckets, tires, open containers.
Ask your pharmacist for advice on a repellent suitable for children’s ages or for pregnancy. After you return home, keep protecting yourself for a few days if you have a fever: the WHO says an infected person can pass the virus to mosquitoes from up to two days before to two days after the fever, and the tiger mosquito is established in parts of Europe and the southern United States.
Dengue vaccine: who is it for?
United States. According to the CDC Yellow Book (page dated 23 April 2025), no dengue vaccines are currently recommended for U.S. travelers. Dengvaxia is recommended only for children aged 9 to 16 with laboratory-confirmed prior infection who live in certain U.S. endemic areas, and the manufacturer is discontinuing it; Qdenga is not available or recommended in the U.S. (CDC dengue vaccine information, updated 22 May 2025).
United Kingdom. According to TravelHealthPro (checked 12 November 2026), Qdenga is licensed in the UK for people aged 4 and over. The JCVI advises considering it for people with a confirmed or likely past dengue infection who travel to risk or outbreak areas or are occupationally exposed; for people with no past dengue, vaccination can be considered after discussion with a travel health clinician. It is a live vaccine, not suitable for people who are immunosuppressed, pregnant, breastfeeding, under 4 or hypersensitive to its components.
The WHO also mentions Qdenga, licensed in some countries. Whatever the country, the decision is made in a consultation, at the same time as your other travel vaccines. No vaccine removes the need to avoid bites.
Decision tree before you leave
- Short city or hotel stay? Repellent from the morning, covering clothing; check the current notice for your destination.
- Long stay, rainy season or an outbreak reported for your destination? See a travel health clinic: the vaccine question may arise (not an option for U.S. travelers at present, see above).
- Have you had dengue before? Tell the doctor: a second infection raises the risk of severe disease.
- Pregnancy, infant, chronic illness? Always get advice before leaving.
- Fever during or after the trip? See a doctor quickly, take acetaminophen (paracetamol) only, and mention the country you visited.
Common mistakes
- Using repellent only in the evening: dengue mosquitoes bite mostly during the day.
- Taking ibuprofen or aspirin for a fever in a dengue area.
- Thinking dengue does not affect cities or hotels.
- Feeling protected because you have already had dengue: another serotype can cause a more severe form.
- Forgetting that it also circulates in the French Caribbean and French Guiana, and in Puerto Rico and other U.S. territories.
Medical costs can be high abroad: check your travel insurance (medical expenses, hospitalization, repatriation).
Frequently asked questions
How do you catch dengue?
Through the bite of an infected Aedes mosquito, mainly Aedes aegypti, sometimes the tiger mosquito. Rarer transmission occurs from mother to child, through transfusion or through transplant.
What are the first symptoms of dengue?
Sudden high fever with headache, pain behind the eyes, aches, nausea and sometimes a rash, 4 to 10 days after the bite according to the WHO.
What medicine should you take for dengue?
There is no specific treatment. The WHO says acetaminophen (paracetamol) can relieve pain and that ibuprofen and aspirin should be avoided. See a doctor.
Is there dengue in Thailand?
Yes: dengue is present in Southeast Asia, including Thailand. Protect yourself from bites day and night and check the current CDC or TravelHealthPro notices.
Is there a dengue vaccine for travelers?
Not for U.S. travelers at present: the CDC does not recommend any dengue vaccine for them. In the UK, Qdenga is licensed for people aged 4 and over and may be considered in some cases; talk to a travel health clinician.
Can you catch dengue in the United States or Europe?
Yes: the CDC reports sporadic local transmission in Florida, Hawaii, Texas, Arizona and California, and TravelHealthPro reports locally acquired cases in Croatia, France, Italy, Madeira and Spain.
Our sources
- World Health Organization, fact sheet « Dengue and severe dengue », consulted on 23 October 2026.
- U.S. CDC, Yellow Book 2026, Dengue (page dated 23 April 2025), and About dengue (updated 22 May 2025), checked 12 November 2026.
- TravelHealthPro (UK National Travel Health Network and Centre), Dengue, checked 12 November 2026.
- Santé publique France, « Dengue » page, consulted on 23 October 2026.
- Institut Pasteur, disease sheet « Dengue », consulted on 23 October 2026.
- Our methodology
Updated November 2026.
