Dengue fever, which is also known as breakbone fever, is a viral illness that is passed on by a type of mosquito called Aedes mosquito. It's found in many countries throughout the world and is particularly common in South East Asia, India, the Caribbean, South and Central America, and Africa. If you travel to one of these areas and don't protect yourself against mosquito bites, you may be at risk of catching dengue fever and other mosquito-borne infections such as malaria.
Most people in the UK who catch dengue fever have travelled to South-East Asia and India. In 2010, 406 people were diagnosed with dengue fever in the UK.
The exact symptoms you get depend on your age.
In older children, teenagers and adults, the most common symptoms of dengue are:
The symptoms of dengue fever usually begin between five and eight days after you get bitten by an infected mosquito. However, the illness can be so mild that you don’t notice any symptoms at all.
Young children with dengue often have a fever with a rash, but other symptoms are minor.
These symptoms can be caused by problems other than dengue fever. If you have recently travelled to an area that is affected by dengue fever and have any of these symptoms, see your GP.
Dengue fever can sometimes develop into a serious, potentially fatal illness.
If you have any of these symptoms, you must seek urgent medical attention.
Dengue fever is caused by a type of virus called a flavivirus, which is transmitted by infected female Aedes mosquitoes. You can catch the virus if you get bitten by an infected mosquito. Mosquitoes become infected when they bite an infected person and are able to pass on the virus for the rest of their life.
There are four different but closely related types (serotypes) of the flavivirus that cause dengue fever. Once you have been infected by one type of the virus you become immune against that type for the rest of your life. However, getting infected with one type of the virus doesn't protect you against catching one of the other three types.
Your GP will ask about your symptoms and examine you. You should tell him or her if you have recently travelled abroad.
If your GP suspects you have dengue fever, he or she may ask you to have a blood test. This is to see whether you have certain antibodies for dengue fever in your blood and will confirm whether you have the infection. Your blood will be sent to a laboratory for testing.
There isn't a specific treatment for dengue fever, but your body will usually fight off the virus within three to four days of the rash appearing.
There are things you can do to help your recovery.
If you're severely dehydrated, have severe symptoms of dengue haemorrhagic fever or your symptoms suddenly become worse, you will need to be admitted to hospital. You will need to have fluids through a drip in your arm. Most people make a full recovery if they receive appropriate treatment.
At present, there aren’t any vaccines or medicines to prevent dengue fever. The only way to prevent catching it is to protect yourself from getting bitten by mosquitoes. Advice for avoiding mosquito bites is as follows.
It's most important to follow these precautions around dawn and dusk, as this is when the Aedes mosquito is most active. However, it's important to remember that the Aedes mosquito can bite at any time of the day or night, so making sure you always take the necessary precautions can help to reduce your risk of catching dengue fever.
You can't catch dengue fever from another person just by being in close contact with them. Very rarely, dengue fever can be passed on through organ transplants, blood transfusions or from an infected mother to her unborn child.
Dengue fever is passed on through the bite of an infected Aedes mosquito. Although you can't catch the disease directly through being in close contact with another person, it can be spread more easily by mosquitoes when people live in crowded conditions. Some evidence has shown that the virus may be able to pass from pregnant, infected mothers to their unborn children, but this is very unlikely to happen. If you're pregnant and think you may have dengue fever, see your GP for advice.
If you have dengue fever, you should take extra care to avoid being bitten by mosquitoes to help stop the spread of the disease to others. You can take the following measures to prevent getting bitten if you're infected.
If you need more information, speak to your GP or a health professional at a travel clinic.
There are several different factors that can affect your chances of getting dengue fever. These include where you're travelling to, how long you're staying and what time of the year you travel.
The number of UK travellers who get dengue has risen over the past few years. This is partly because the disease is becoming more common worldwide and travel to affected areas has increased.
It's difficult to say for certain what your individual risk of catching dengue fever is – everyone who travels to an area where the virus is present is at some level of risk. Travellers who spend a long time in areas where dengue fever is common (such as expatriates or aid workers) have a greater risk. However, even short-term visitors may still be exposed.
The best advice is to always protect yourself from getting mosquito bites if you're travelling to an affected area.
This depends on the amount of exposure to dengue fever you're likely to have and the type of protection from mosquito bites you prefer.
Products containing DEET are available in several different concentrations – the higher the concentration, the longer the duration of protection. Concentrations of 20 percent DEET have been shown to provide about one to three hours of protection and higher concentrations provide longer-lasting protection. However, the duration of action appears to level off at a concentration of about 50 percent. This means that concentrations above 50 percent don't give you any significant added benefit, so it's generally not necessary to use products of a higher concentration than this.
The use of DEET-containing products isn't advised for babies under two months. DEET-based products are considered safe if you're pregnant or breastfeeding; however, it’s advisable to stick to those with a concentration no greater than 50 percent.
You should always use any DEET-containing products according to the manufacturer's instructions, especially since some manufacturers will advise about their own age restrictions.