Dengue
Dengue is an infection caused by the dengue virus of which there are four different types (serogroups) DENV-1, DENV-2, DENV-3 and DENV-4. The disease is spread through the bite of an infected mosquito. The mosquitoes that spread dengue usually breed in urban areas close to human habitation and are most active during daylight hours. Although unpleasant, dengue is usually a self-limiting illness. However, a small, but significant, number of people can develop more life-threatening infection (severe dengue).
The disease is common in the tropics. Affected areas include the Caribbean, South and Central America, Africa, Asia and the Pacific Islands. Although less common, outbreaks are increasingly being reported outside tropical areas, including in Europe, with locally acquired cases reported in Croatia, France, Italy, Madeira and Spain.
Dengue does not occur naturally in the United Kingdom (UK) but is reported in travellers returning from dengue affected areas. Cases of dengue in UK travellers are increasing, with most reported in travellers who visited Asia, Central and South America or the Caribbean. Country-specific information on dengue is available on our Country Information pages and current dengue outbreaks are listed on our Outbreak Surveillance section.
All travellers to dengue endemic countries are at risk of dengue infection. The chance of becoming infected with dengue is determined by several factors, including destination, length of exposure and season of travel. Risk is thought to be higher during periods of intense mosquito feeding activity (two to three hours after dawn and during the early evening). Travellers, who spend long periods in areas where dengue is common, are at increased risk, but even short-term visitors can be infected.
Approximately 40 to 80 percent of people infected with dengue remain symptom-free. If symptoms do occur, the illness usually begins abruptly with a high fever, and is often accompanied by a severe headache, muscle and joint pain, nausea, vomiting and a rash. Most infections are self-limiting, with a rapid recovery three to four days after the rash appears.
A small number of people develop more severe illness with symptoms which can include dangerously low blood pressure (shock), fluid build-up in the lungs and severe bleeding. There is no specific drug treatment for severe dengue illness, although hospital admission and careful management of fever, fluid balance and pain can help with recovery. If left untreated, severe dengue illness can be fatal. With good medical care, death due to severe dengue is typically less than one percent.
Prevention
Travellers can check our Country Information pages for information on the risk of dengue at their destination. Mosquito bite avoidance is recommended. As dengue is spread by day-biting mosquitoes, particular care with bite avoidance is advised during the day, especially around dawn and dusk.
A vaccine, Qdenga®▼ has been licensed in the UK for the prevention of dengue disease in individuals from 4 years of age.
The UK Joint Committee on Vaccination and Immunisation (JCVI) has advised that Qdenga®▼ vaccine can be considered for individuals aged 4 years of age and older who have a confirmed or likely history of dengue infection in the past and are:
- planning to travel to dengue where there is a risk of dengue infection or areas with an ongoing outbreak of dengue
or
- exposed to dengue virus through their work, for example, laboratory staff working with the virus.
Vaccination can be considered in those who have not had dengue in the past. In these situations, discussion with a travel health clinician experienced in assessing the balance of potential risks and benefits of Qdenga®▼ is recommended.
Blood tests for previous dengue infection may not be 100 percent reliable and assessment must be made of previous tests for dengue, likely exposure and clinical history. In the UK, tests for previous dengue infection are usually offered privately, (a fee is charged to the individual being tested). Guidance on investigating previous dengue infection and use of Qdenga®▼ is available in the UKHSA 'green book' Immunisation against infectious disease, dengue chapter.
Qdenga®▼ is a live vaccine (it contains live, attenuated dengue virus) and cannot be given to travellers who are immunosuppressed (have a weakened immune system), pregnant or breastfeeding. This vaccine is also contraindicated (cannot be given) for those with hypersensitivity to any component of the vaccine and for children under four years of age.
Resources
- More detailed information on can be found in our dengue factsheet
- UKHSA: Dengue: guidance, data and analysis
- UKHSA: Dengue chapter 'green book' Immunisation against infectious disease
- Joint Committee on Vaccination and Immunisation (JCVI): Minutes of meeting February 2026
- World Health Organization (WHO): Fact sheets: dengue
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Recent News on Dengue
Updated dengue 'green book' chapter published
The dengue chapter of the 'green book' (Immunisation against infectious disease) has been updated
Updated: 17 September 2026Worldwide dengue risk reminder
Dengue is a mosquito-spread virus found in tropical and subtropical world regions, including parts of mainland Europe
Updated: 11 June 2026Changes to the Country Information pages: dengue vaccine recommendations
NaTHNaC has reviewed and updated the dengue country-specific information and vaccine recommendations
Updated: 02 May 2025Mosquito and insect spread infections in the Caribbean
An increase in cases of mosquito and insect spread infections have been reported in the Caribbean region
Updated: 24 December 2024Recent Dengue Outbreaks
Dengue in Bangladesh
As of 19 October 2026, a total of 114,251 dengue cases and 352 deaths have been reported in Bangladesh in 2026. Please see our Topics in Brief article for further details on dengue.
As of 8 October 2026, a total of 94,151 dengue cases, with 294 deaths, have now been reported in Bangladesh during 2026. Please see our Topics in Brief article for further details on dengue.
Source: StateAs of 6 August 2026, a total of 17,880 dengue cases (59 deaths) have been reported in Bangladesh during 2026. Dhaka division has reported the highest number of cases, followed by Barishal, Chattogram and Khulna divisions. Please see our Topics in Brief article for further details on dengue.
Source: StateAs of 30 November 2025, a total of 95,081 dengue cases and 380 deaths have been reported in Bangladesh during 2025. Please see our Topics in Brief article for further details on dengue.
Source: WHOAs of 10 November 2025, a total of 79,722 dengue cases and 315 deaths have been reported in Bangladesh in 2025. Most cases have been reported in Barishal (18,627 cases) followed by Dhaka (13,455 cases). Please see our Topics in Brief article for further details on dengue.
Source: StateAs of 2 November 2025, a total of 71,675 dengue cases and 283 deaths, have been reported in Bangladesh for 2025. Currently, the highest number of cases and deaths were reported in October 2025, with 22,520 cases and 80 deaths. Please see our Topics in Brief article for further details on dengue.
Source: StateAs of 26 October 2025, a total of 66,423 cases (including 269 deaths) of dengue have been reported in Bangladesh during 2025. Please see our Topics in Brief article for further details on dengue.
Source: StateAs of 19 October 2025, a total of 59,849 cases (including 245 deaths) of dengue have been reported in Bangladesh during 2025. Please see our Topics in Brief article for further details on dengue.
Source: StateAs of 22 September 2025, a total of 42,509 cases of dengue have been reported in Bangladesh. Please see our Topics in Brief article for further details on dengue.
Source: StateAs of 2 September 2025, a total of 32,501 dengue cases, and 125 deaths have been reported in Bangladesh since 1 January 2025. Please see our Topics in Brief article for further details on dengue.
Source: StateAs of 3 August 2025, a total of 21,670 dengue cases and 84 deaths have been reported in Bangladesh since 1 January 2025. Please see our Topics in Brief article for further details on dengue.
Source: StateAs of 13 July 2025, a total of 15,569 dengue cases with 59 dengue-related deaths have been reported during 2025. This represents a large increase compared to the corresponding period in 2024. Please see our Topics in Brief article for further details on dengue.
Source: WHOOn 11 June 2025, 5,303 dengue cases and 23 deaths have been reported from 1 January to 11 June 2025. Please see our Topics in Brief article for further details on dengue.
Source: StateDengue in USA
As of 10 October 2026, 368 cases of locally acquired dengue have been reported in Florida, USA. The outbreak has surpassed Florida's previous annual high of 200 cases, reported in 2023. DENV-2 and DENV-3 have been identified amongst cases in 2026. Please see our Topics in Brief article for further details on dengue.
As of 3 October 2026, 296 cases of locally acquired dengue have been reported in Florida, USA. The outbreak has surpassed Florida's previous annual high of 200 cases, reported in 2023. DENV-2 and DENV-3 have been identified amongst cases in 2026. Please see our Topics in Brief article for further details on dengue.
Source: StateAs of 26 September 2026, 252 cases of locally acquired dengue were reported in Florida, USA. The outbreak has surpassed Florida's previous annual high of 200 cases, reported in 2023. Dengue serotypes 2 and 3 have been identified amongst cases in 2026. Please see our Topics in Brief article for further details on dengue.
Source: StateBetween 6 and 12 September 2026, 41 new cases of locally acquired dengue were reported in Florida, bringing the total for 2026 to 152. Please see our Topics in Brief article for further details on dengue.
Source: StateAs of 29 August 2026, 73 cases of locally acquired dengue have been confirmed in Florida, USA. Please see our Topics in Brief article for more details on dengue.
Source: StateAs of 22 August 2026, a total of 41 locally acquired dengue cases have been reported in Florida in 2026. Serotypes DENV-2 and DENV-3 have been confirmed. Please see our Topics in Brief article for further details on dengue.
Source: StateAs of 15 August 2026, a total of 23 locally acquired cases of dengue have been confirmed in Florida during 2026. Serotypes DENV-2 (20) and DENV-3 (2) have been confirmed. Please see our Topics in Brief article for further details on dengue.
Source: StateAs of 3 August 2026, a locally acquired case of dengue has been confirmed in Florida, Miami-Dade County. Please see our Topics in Brief article for further details on dengue.
Source: StateAs of 28 July 2026, a locally acquired case of dengue has been confirmed in Hillsborough County, Florida. Please see our Topics in Brief article for further details on dengue.
Source: StateDengue in Italy
As of 8 October 2026, the Italian authorities confirmed the 68 locally acquired dengue cases reported for 2026 were in the following regions: Campania (2), Lazio (1), Lombardy (2), Puglia (20), Tuscany (36) and Veneto (7). Please see our Topics in Brief article for further details on dengue.
As of 7 October 2026, a total of 68 confirmed locally acquired dengue cases have been reported for 2026 in Italy. Please see our Topics in Brief article for further details on dengue.
Source: ECDCAs of 29 September 2026, a total of 59 confirmed locally acquired dengue cases have been reported for 2026 in Italy. Please see our Topics in Brief article for further details on dengue.
Source: StateAs of 22 September 2026, a total of 47 confirmed locally acquired dengue cases have been reported for 2026 in Italy. The cases have been reported in Puglia (13), Tuscany (31), Lombardy (2), Campania (1) regions of Italy. Please see our Topics in Brief article for further details on dengue.
Source: StateAs of 8 September 2026, a total of 24 confirmed locally acquired dengue cases have now been reported for 2026 in the Puglia and Tuscany regions of Italy. Please see our Topics in Brief article for further details on dengue.
Source: StateAs of 30 August 2026, a total of three confirmed locally acquired dengue cases have been reported during 2026 in the Puglia and Tuscany regions of Italy. Please see our Topics in Brief article for further details on dengue.
Source: StateDengue in Marshall Islands
As of 25 September 2026, 112 confirmed dengue cases have been reported in the Marshall Islands. DENV-1 has been detected. No dengue cases were reported in the Marshall Islands in 2025. Please see our Topics in Brief article for further details on dengue.
As of 24 August 2026, Marshall Island's Ministry of Health and Human Services has reported 17 confirmed dengue cases. DENV-1 has been confirmed in circulation. Please see our Topics in Brief article for further details on dengue.
Source: State
