Dengue virus disease
Dengue virus disease
Cause of dengue
Dengue is caused by infection with one of four closely related viruses known as DEN-1, DEN-2, DEN-3 and DEN-4. Infection with one serotype gives you lifelong immunity to that particular serotype of dengue virus. However, the infection does not offer immunity to the other three types, so it is possible to contract dengue again. A person who has had dengue once is at increased risk of experiencing more severe dengue symptoms if they get infected again.
Symptoms of dengue
The typical signs and symptoms of dengue may include:
high temperature
severe headache
pain behind the eyes
joint and muscle aches
appetite loss
nausea and vomiting
generally feeling unwell (malaise)
skin rash.
In most cases, symptoms resolve within one to two weeks.
Symptoms of severe dengue
Although rare in Australia, certain people can develop severe dengue infection. Babies, young children, and people who have had dengue more than once are at increased risk of this complication.
Warning signs of more severe dengue include the typical signs and symptoms in additional to some or all of the following:
severe abdominal pain
restlessness and fatigue
persistent vomiting (which may include blood)
shortness of breath
nose bleeds and bleeding gums.
Most people who experience these symptoms recover fully. A small number of people who experience these symptoms will go on to have severe dengue which can include:
severe bleeding
extremely low blood pressure caused by blood loss (shock)
coma
death.
Where dengue commonly occurs
Dengue is common throughout tropical and subtropical areas of:
Africa
the Caribbean
Central America
Central Pacific
China
India
the Middle East
South America
Southeast Asia
the South Pacific.
Dengue in Australia
Cases of dengue occur in northern Queensland from time to time when travellers who have been infected overseas return and introduce the virus to the local mosquito population. To date, it isn’t as common as in other subtropical regions.
How dengue is spread
Dengue is not transmitted (spread) from person to person. Only infected mosquitoes transmit dengue. It is thought that the mosquito contracts the virus when it bites an infected person. The mosquito is then infectious for the rest of its life and can spread the virus every time it bites someone.
At least three different kinds of mosquito in Australia are suspected to be dengue carriers. They are
Aedes aegypti
,
Aedes scutellaris
and
Aedes katherinensis
. These mosquitoes are found in northern Queensland, the Northern Territory and northern Western Australia. They are not found in Victoria.
Avoid mosquito bites and avoid dengue in commonly affected areas
Protect yourself against
mosquito bites
to avoid dengue (and other mosquito-borne diseases) in dengue-affected areas. Suggestions include:
Wear socks and light coloured, long pants and long-sleeved shirts. Loose fitting clothing makes it harder for mosquitoes to bite you through your clothes.
Wear mosquito repellent that contains the active constituents DEET (diethyltoluamide) or picaridin. Reapply regularly and make sure you follow directions for safe use on the label. (For kids, it can be safer to spray insect repellent on their clothes rather than their skin.)
Apply insect repellent first thing in the morning because dengue mosquitoes bite during the day, both outdoors and inside homes and buildings.
Apply a product, such as permethrin, to your clothes or bedding.
Use a bed net (mosquito net).
Stay in air-conditioned accommodation with flyscreens on the windows.
Diagnosis of dengue
See a doctor immediately if you think you may have dengue virus. Early diagnosis is important to reduce the risk of complications and avoid further spread of the virus.
Your doctor will ask about your medical history, including any travel, and will do a physical examination. Blood tests are required to diagnose dengue.
Treatment for dengue
There is no specific treatment for dengue virus. Medical care aims to manage the symptoms and reduce the risk of complications while the person recovers. Most cases of uncomplicated dengue virus resolve fully within one to two weeks.
During this time, your doctor may advise:
bed rest
plenty of fluids
medication to reduce fever, such as paracetamol (do not take aspirin because of its blood-thinning properties).
Hospital admission is usually required if the person develops warning signs of more severe dengue. Treatment for these complications may include intravenous fluids and replacement of lost electrolytes.
Where to get help
Your GP (doctor)
Smartraveller
External Link
Nurse-on-Call
Tel.
1300 60 60 24
– for expert health information and advice (24 hours, 7 days)