The symptoms of dengue fever usually develop around 3 to 14 days after a person is exposed to the virus, with an average incubation period of 4 to 7 days.
When symptoms do manifest, they usually begin with a sudden and large rise in temperature that can reach as high as 41ºC (105.8ºF).
The major symptoms of dengue fever include:
- Very high fever that may be accompanied by chills or severe shivering
- Severe headache and eye pain
- Severe weakness and fatigue
- Severe pain in the bones, and joints. The illness is also referred to as “break-bone fever”
- Severe muscle pain in the lower back, arms and legs
- Nausea and vomiting
- Abdominal cramps
- Loss of appetite
- Red rash across the torso that spreads to the limbs and face
- Facial flushing
- In a very small number of cases, the illness becomes severe and leads to life-threatening complications. Severe dengue can damage organs and cause bleeding from the gums, under the skin and blood may also be passed in the urine, stool or vomit. This is called dengue haemorrhagic fever.
- Another serious complication is dengue shock syndrome, characterized by abdominal pain, vomiting and a significant fall in blood pressure that can lead to clamminess, a weak pulse, dizziness and even loss of consciousness.
In most cases, the symptoms resolve in a week or two but full recovery of strength may take a few weeks, during which time a person may be weak and prone to secondary infections.