What is Dengue?

Dengue is the most common and fastest-spreading mosquito-borne virus in the world1 with an estimated 100–400 million infections occurring each year. The mosquitoes that transmit the dengue virus mainly live in tropical and sub-tropical climates, mostly in urban and semi-urban areas2. Currently, the disease is endemic in over 100 countries, in the WHO Regions of Africa, the Americas, the Eastern Mediterranean, South-East Asia and the Western Pacific2.

Climatic change is one of the main factors contributing to the intensification of dengue disease transmission.3 In 2019, the World Health Organization (WHO) reported an increase in the number of dengue cases since 2000, with cases rising from 505,430 in 2000 to approximately 5.2 million in 20192

There are different types (4 serotypes) of the virus that can cause dengue1. You can lower your risk of contracting dengue by avoiding mosquito bites, especially during the day.2

The illness ranges from asymptomatic infection through undifferentiated fever to severe dengue4. With symptomatic dengue, symptoms such as fever, headache, joint and muscle pain, rash, nausea, pain behind the eyes, swollen glands, and vomiting usually begin 4-10 days after infection and last for 2-7 days2.

An estimated 1 in 4 dengue virus infections are symptomatic and approximately 1 in 20 dengue patients with dengue virus progress to develop further symptoms that are severe and potentially life-threatening. This is called severe dengue.5

5 important facts about Dengue


The risk of dengue is now present in more than 100 countries worldwide2

In 2022, a total of 114 cases of dengue were confirmed in Italy, all of which were associated with travel abroad6

Patient Ben

A second dengue infection increases the risk of severe dengue2

The mosquitoes that spread the disease are active during the day2

Mozzie Spray

Travelers to high dengue risk countries can decrease the chance to be infected by taking measures to protect themselves from mosquito bites2


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  2. WHO. Dengue and severe dengue (https://www.who.int/news-room/fact-sheets/detail/dengue-and-severe-dengue - ultimo accesso giugno 2023).
  3. Bhatia, S. et al. A Retrospective Study of Climate Change Affecting Dengue: Evidences, Challenges and Future Directions. Front. Public Health 10, (2022).
  4. Chawla, P., Yadav, A. & Chawla, V. Clinical implications and treatment of dengue. Asian Pac. J. Trop. Med. 7, 169–178 (2014).
  5. CDC. Dengue: Clinical presentation (https://www.cdc.gov/dengue/healthcare-providers/clinical-presentation.html - ultimo accesso giugno 2023).
  6. Epicentro. Febbre dengue (https://www.epicentro.iss.it/febbre-dengue/aggiornamenti - ultimo accesso giugno 2022).
  7. Tiga, D. C. et al. Persistent Symptoms of Dengue: Estimates of the Incremental Disease and Economic Burden in Mexico. Am. J.Trop. Med. Hyg. 94, 1085–1089 (2016).
  8. CDC. Dengue: Symptoms and Treatment (https://www.cdc.gov/dengue/symptoms/index.html - ultimo accesso giugno 2023).
  9. WHO. What are the symptoms of dengue fever and severe dengue? (https://www.who.int/news-room/questions-and-answers/item/dengue-and-severe-dengue - ultimo accesso giugno 2023).
  10. CDC. Dengue: Prevent Mosquito Bites (https://www.cdc.gov/dengue/prevention/prevent-mosquito-bites.html# - ultimo accesso giugno 2023).
  11. CDC. Mosquito Bite Symptoms and Treatment (https://www.cdc.gov/mosquitoes/mosquito-bites/symptoms.html - ultimo accesso giugno 2023).
  12. MedlinePlus. Dengue Fever Test (https://medlineplus.gov/lab-tests/dengue-fever-test/ - ultimo accesso giugno 2023).
  13. CDC. Your child or family member may have dengue fever according to their clinical history and physical examination (https://www.cdc.gov/dengue/resources/cs_205910-a.dengue-patient-ed-eng.final.pdf - ultimo accesso giugno 2023).
  14. Wilder-Smith, A. Dengue infections in travellers. Paediatr. Int. Child Health 32, 28–32 (2012).
  15. ECDC. Autochthonous vectorial transmission of dengue virus inmainland EU/EEA, 2010-present (https://www.ecdc.europa.eu/en/all-topics-z/dengue/surveillance-and-disease-data/autochthonous-transmission-dengue-virus-eueea - ultimo accesso giugno 2023).
  16. Stanaway JD et al. The global burden of dengue: an analysis from the Global Burden of Disease Study 2013. Lancet Infect Dis 2016; 16: 712–23.