Dengue fever is caused by a group of closely related viruses that are transmitted between people by the Aedes aegypti mosquito. The World Health Organisation (WHO) ranks dengue as the most important mosquito-borne viral disease in the world occurring in over 100 countries with an estimated 50-100 million cases each year.
Dengue haemorrhagic fever (DHF) is a potentially fatal complication of dengue fever that is characterised by high fever and internal haemorrhaging, Today DHF affects most Asian countries and has become a leading cause of hospitalisation and death among children and adults in the region.
Currently there is no cure for dengue or effective way to control the spread of the virus, other than attempting to reduce mosquito breeding sites and applying insecticides.
Dengue became a widely established disease throughout the tropics with the development of commercial shipping during the 18th century. In the last 50 years, incidence of dengue fever has increased 30-fold. Many factors are responsible for this, however, it is clear that rapid population growth, urbanisation and increased international air travel have all been driving forces associated with the increase in people affected by dengue.
Dengue is transmitted to humans from the bite of the Aedes aegypti or more rarely the Aedes albopictus mosquito, both of which feed exclusively during daylight hours.
The Aedes aegypti mosquito does not naturally have the dengue virus; it has to pick it up from a person sick with dengue. Therefore the transmission of the dengue virus cannot be spread directly from person to person without the aid of the mosquito.
Unfortunately, there is no effective vaccine for dengue; however there are many ongoing vaccine research programs in various stages of development. There is also no specific medication for treatment of a dengue infection. People infected with the virus are commonly prescribed painkillers and advised to rest and drink plenty of fluids. Those diagnosed with dengue are also asked to wear insect repellent to prevent the spread of the disease to other mosquitoes and potentially other people.
Dengue is considered endemic to the Americas, south-east Asia, western Pacific, Africa and the eastern Mediterranean. The most significant epidemics occur in south-east Asia, the Americas and the western Pacific.
Dengue is not endemic to Australia but outbreaks do occur in far north Queensland when infected travellers or residents arriving from overseas introduce the virus into the local mosquito population.3
There is not continuous transmission of dengue in Australia; rather outbreaks are initiated by travellers and residents arriving into Australia with the dengue virus, and then being bitten by local mosquitoes.1 Australia has a history of dengue epidemics dating back to 1879, most of which occurred in Queensland. During the wet season of 2008-09 Queensland Health declared a dengue epidemic in North Queensland, the worst in over 50 years with over 1,000 cases reported.
Classic dengue fever lasts about two to seven days, followed by a long recovery period. Typical symptoms may include but are not limited to:
If someone presents with the symptoms listed above they should immediately see a doctor.