What is dengue fever?

Dengue fever or dengue virus infection is an illness with symptoms that are like a bad case of the flu. Dengue fever is caused by a virus carried by mosquitoes. These mosquitoes are mainly found in Asia, Africa and South America.

Most areas of Australia do not have mosquitoes that carry dengue virus. Outbreaks of the disease still occur in North Queensland every year. This happens when someone becomes infected overseas and is then bitten by a mosquito in Australia. That mosquito can then spread dengue virus to others.

Dengue fever is a notifiable disease in Australia. This means that if your doctor finds out you have dengue fever, they must report it to the Australian Government Department of Health. Read more on notifiable diseases.

What are the symptoms of dengue fever?

If you have dengue fever, you may have:

• a sudden fever or chills
• headache, particularly pain towards the front of your head or behind your eyes
• swollen glands
• muscle and joint pain
• fatigue (feeling very tired)
• abdominal (tummy) pain, nausea or vomiting
• a faint red rash

These symptoms can be mild or severe.

Symptoms usually appear 4 to 10 days after being bitten by the mosquito and last for 2 to 7 days.

Most people who have dengue fever recover in about a week. Sometimes, the infection is more serious, and occasionally it's fatal (causes death).

What are the symptoms of severe dengue fever?

Severe dengue (also known as dengue haemorrhagic fever) is rare but can lead to death.

Symptoms of severe dengue fever can start 3 to 7 days after the first symptoms start.

People with severe dengue fever feel very unwell and have extra symptoms such as:

• severe abdominal pain
• rapid breathing
• persistent vomiting
• vomit with blood in it
• bleeding gums
• unexpected bleeding
• restlessness

Dengue haemorrhagic fever occurs most often in children and young adults.

Previous infections with any type of dengue virus, even years apart, increases your risk of developing severe dengue fever.

What causes dengue fever?

Dengue fever is caused by one of 5 dengue viruses that are carried by mosquitoes.

The dengue virus is mostly spread by the dengue mosquito (aedes aegypti). It can also be spread by other types of Aedes mosquito such as the Asian Tiger mosquito (Aedes albopictus).

Dengue fever is not passed directly from person to person.

When should I see my doctor?

If you have symptoms of dengue fever and are concerned, speak with your doctor right away. If your doctor is not available, Medicare Urgent Care Clinics can help. These clinics are open for longer hours than regular GP clinics, and provide bulk-billed medical care for anyone with a Medicare card.

How is dengue fever diagnosed?

Your doctor will assess you by:

• discussing your symptoms and recent travel history
• examining you
• ordering blood tests

They may need to order a second blood test to help diagnose dengue fever.

How is dengue fever treated?

There is no specific medicine to treat dengue fever.

People who have dengue fever should get medical advice. It's also important to:

• rest
• drink plenty of fluids

You can reduce the fever using paracetamol.

If you have dengue fever, do not take non-steroidal anti-inflammatory drugs (NSAIDs), such as aspirin and ibuprofen. These can increase your risk of bleeding.

If possible, have someone stay at home to look after you.

Can dengue fever be prevented?

There is currently no vaccine to prevent first-time infection with dengue fever. The best way to prevent it is to avoid being bitten by mosquitos.

The Australian Government is taking steps to control and reduce the spread of the virus. This includes the release of Wolbachia-infected mosquitoes.

How to prevent mosquito bites:

• Wear loose, long-sleeved, light-coloured clothing. Remember to also wear socks and covered shoes. Mosquitoes will bite through tight clothing.
• Use a mosquito repellent on exposed skin that contains DEET, picaridin or oil of lemon eucalyptus.
• Regularly check and empty any containers of still water around your home such as pot plant saucers. Mosquitos breed in still water.

The mosquitoes that spread dengue virus will bite throughout the day. They're most active in the hours after sunrise and before sunset.

Be extra careful when in areas with a higher risk of mosquito-borne diseases. This might be overseas or in Central and Far North Queensland. Use window screens or air conditioning.

If someone in your house has dengue fever, it's very important to avoid mosquito bites. Mosquitoes can carry the infection from one person to another.

Complications of dengue fever

Some complications or signs of severe illness with dengue fever include:

• dehydration
• bleeding
• hepatitis (inflammation of your liver)
• shock
• heart and blood vessel issues
• neurologic effects on the brain, spine and nerves
• lymphatic damage such as an enlarged spleen

Severe dengue fever is rare but can lead to death. It needs urgent medical attention. If you experience any severe symptoms, seek medical care immediately.

Resources and support

Visit Smartraveller for information on global dengue fever outbreaks, and advice about preventing infectious diseases while overseas.

Learn more about the health risks of mosquitoes and the viruses they may carry.

For more information you can call the healthdirect helpline on 1800 022 222 (known as NURSE-ON-CALL in Victoria). A registered nurse is available 24 hours a day, 7 days a week.

Other languages

The World Health Organization has information, in several languages, for travellers visiting high risk areas for dengue virus infection.

Smartraveller has general travel advice in a range of community languages.

Looking for information for people living in the Torres Strait?

Defend against dengue provides information and steps to prevent infection.