Dengue fever is a viral infection. It's caused by the dengue virus and is spread by mosquitoes.
The infection is usually mild and passes after about 1 week. But in rare cases, it can be very serious and life-threatening.
Mosquitoes in Ireland do not spread the dengue virus. But you could catch it if you visit or live in other places. For example, Asia, the Americas or the Caribbean.
Use insect repellent and other measures to avoid mosquito bites if you visit an area where the virus is found.
Symptoms of dengue fever
Symptoms of dengue fever usually start suddenly, about 5 to 8 days after you become infected.
Symptoms can include:
- a temperature of 38 degrees Celsius or above
- feeling hot or shivery
- a severe headache
- pain behind your eyes
- muscle and joint pain
- feeling sick
- vomiting
- a widespread red rash
- tummy pain and loss of appetite
The symptoms normally pass after about 1 week. But you may feel tired and a little unwell for a few weeks afterwards.
In rare cases, severe dengue fever can develop after the initial symptoms.
Non-urgent advice: Contact your GP if
you visited a country that has the dengue virus and you:
- develop a fever or flu-like symptoms within 2 weeks
Tell the GP where you travelled to.
Go to a GP or hospital if you develop symptoms while travelling or living in an area where dengue is common.
Treatment for dengue fever
There's no cure or single treatment for dengue fever. You can only relieve the symptoms until the infection has gone.
You can usually look after yourself at home.
It may help to:
- take paracetamol for pain and fever
- drink plenty of fluids to prevent dehydration
- get plenty of rest
Do not take aspirin or ibuprofen. These can cause bleeding problems in people with dengue.
If you are abroad, only drink bottled water from a bottle that was properly sealed.
You should start to feel better after about 1 week. But it may be a few weeks before you fully recover.
Get medical advice if your symptoms do not improve. A GP can check if there is another cause for your symptoms. You may need a blood test to confirm that you have dengue.
Where the dengue virus is found
You can get dengue if you're bitten by an infected mosquito. The mosquitoes that carry the dengue virus bite during the day.
Mosquitoes in Ireland do not spread dengue virus. Cases in Ireland usually happen to people who recently travelled to an area where it is common.
Dengue virus is found in parts of:
- Southeast Asia
- the Caribbean
- the Indian subcontinent
- South and Central America
- Africa
- the Pacific Islands
- Australia
- some southern areas of North America
There's also a risk of getting dengue from spring to November in parts of southern Europe.
European countries where dengue has been found include:
- Croatia
- France
- Italy
- Spain
- Portugal and Madeira
Preventing dengue virus
You can prevent dengue virus by avoiding mosquito bites.
There are 4 types of the dengue virus. This means you can get it again if you've had it before. You may only be immune to 1 type of the virus.
To reduce your risk of bites:
- use insect repellent
- wear loose clothing
- sleep under a mosquito net - a net treated with insecticide is best
- be aware of your environment - dengue mosquitoes breed in still water in urban areas
Speak to a GP, practice nurse or visit a travel clinic before travelling. They can give you advice about what you can do to avoid dengue fever and other travel illnesses.
Insect repellent
Use insect repellent on your skin and in sleeping environments. Remember to reapply it frequently. The most effective repellents contain diethyltoluamide (DEET).
Do not use a spray that contains DEET on infants younger than 2 months old. Ask your pharmacist for advice. Follow the manufacturer's instructions.
Clothing
Mosquitoes can bite through tight-fitting clothes. Trousers, long-sleeved shirts, and socks and shoes (not sandals) are best.
Dengue vaccine
A vaccine can help prevent against dengue disease. The vaccine available in Ireland is called Qdenga.
Adults and children age 4 and older can get the vaccine. But it is usually only given to people who had dengue before. This is to prevent severe dengue.
The vaccine contains attenuated (weakened) versions of dengue virus serotypes 1, 2, 3 and 4.
You cannot get the vaccine if you:
- have a weak immune system
- are pregnant or breastfeeding
Severe dengue fever
In rare cases, dengue fever can be very serious and potentially life-threatening. This is called severe dengue or dengue haemorrhagic fever.
You may be most at risk of severe dengue fever if you had dengue before and get infected again. It's very rare for travellers to get severe dengue fever.
Emergency action required: Call 112 or 999 if
you have symptoms of severe dengue fever such as:
- severe tummy pain
- a swollen tummy
- being sick repeatedly and vomiting blood
- bleeding gums or bleeding under the skin
- breathing difficulties or fast breathing
- cold, clammy skin
- a weak but fast pulse
- drowsiness or loss of consciousness
Go to an emergency department or call the local emergency number if you are abroad.
Content supplied by the NHS and adapted for Ireland by the HSE
