Dengue (Breakbone Fever, Dandy Fever)

What is Dengue fever?

Dengue fever is a viral disease transmitted to humans from the bite of an infected mosquito, usually the Yellow fever mosquito or Egyptian tiger mosquito (Aedes aegypti). The Asian tiger mosquito, Aedes albopictus, can also be an important vector of dengue fever. Currently there are four known different strains of the dengue virus. There is no vaccination or specific treatment for Dengue. Treatment is symptomatic.

What type of illness does the Dengue virus cause?

Dengue fever usually manifests itself by the sudden onset of high fevers, severe frontal headache, and intense joint and muscle pains that often lead to contortions. Hence, the name "breakbone fever". Because of the body posture and gait assumed by victims of dengue, the disease was also called "dandy fever". Often there seems to be a partial recovery after 1 to 2 days before symptoms return. Many patients also suffer from nausea, vomiting, and skin rash.

The illness typically begins 4 to 7 days after a person is bitten by an infected mosquito, but it can occasionally take up to 14 days for symptoms to appear.

A Dengue infection can occasionally cause a more severe and potentially life-threatening illness associated with internal bleeding, Dengue Haemorrhagic Fever (DHF), or an illness associated with a sudden loss in blood pressure, Dengue Shock Syndrome (DSS).

The risk of having these more severe types of Dengue infection is higher if someone has had a previous Dengue infection with a different virus strain.

Where is Dengue fever found?

Dengue fever is found in the tropical and subtropical regions of the world, including Southeast Asia, the Indian subcontinent, Africa, and the Americas. Dengue has been around since the 1780's and has caused numerous global pandemics throughout these regions. Dengue epidemics result in thousands of fatalities annually. It is the most important mosquito-borne disease behind Malaria.

Southeast Asia has always been affected by Dengue fever epidemics. A large-scale pandemic broke out in Southeast Asia in the 1950's and spread around the world. The more severe type of Dengue fever known as Dengue Haemorrhagic Fever (DHF) has become a frequent cause of illness and death among children in these regions. In 2007, Indonesia reported 160,000 cases of Dengue fever with over 1000 deaths. Other countries such as Cambodia, Malaysia, the Philippines, Thailand, and Vietnam each reported tens of thousands of cases in 2007.

Dengue fever has been sweeping through Latin America over the last several years as well. In 2002, an outbreak hit Rio de Janeiro and one million people were infected. In 2007 alone, Brazil reported over half a million cases, Colombia reported 42,000 cases, Venezuela reported 82,000 cases and Paraguay reported over 28,000 cases. The number of cases for 2008 is likely to be similar.

What is the risk for Europe?

In the past there have been a number of Dengue epidemics in Europe. The last big outbreak occurred in Greece between 1927 and 1928 with more than 1000 deaths and one million cases. In these past epidemics, the vector was the Yellow fever mosquito Aedes aegypti, which was still widely present in southern Europe. After the Yellow fever mosquito had been eradicated due to the extensive use of DDT and better sanitary conditions, Dengue was no longer a threat.

However, with the Asian tiger mosquito (Aedes albopictus) now colonizing the areas where Aedes aegypti was once present, the risk of Dengue fever has returned to Europe. With this widespread distribution of tiger mosquitoes throughout Europe and the increase in international travel, it is only a matter of time before one of these travelers brings back the Dengue virus to Europe and begins another epidemic.