What causes dengue fever? 

Dengue fever is caused by virus. They are passed to humans by infected mosquitoes. The bite can allow the virus to enter the bloodstream and spread through the body. Once in the body the virus may cause dengue fever.

In Vietnam, Dengue fever is very common. Dengue fever is suspected if fever lasts more than 3 days 

What are the symptoms?

  • Severe headache
  • Severe eye pain
  • Chills and fever
  • Muscle and or bone pain
  • Red or purple spots in skin
  • Minor bleeding in nose or gum
  • Easy bruising
  • Nausea/vomiting

The fever tends to decline within 3-7 days after symptoms begin. As the fever decreases, warning signs of a severe infection may appear.


Watch for warning signs 3 to 7 days after symptoms began even if temperature declines
Go IMMEDIATELY to an emergency room if any of the following warning signs appear:

  • Drowsiness or irritability
  • Lightheadedness
  • Pale, cold, or clammy extremities especially in the 4th-5th day of disease.
  • Difficulty breathing
  • Abdominal pain
  • Persistent vomiting
  • Red spots or patches on the skin
  • Bleeding from nose or gums
  • Vomiting blood
  • Black stools or
  • blood in urine

A severe infection can lead to shock and organ failure.

How dengue fever is diagnosed?

Your doctor will ask about your symptoms and medical history. A physical exam will be done. Blood tests may be done to look for diagnosis and complications

How dengue fever is treated?

You may be referred to a specialist.

There are no medications currently available that can provide a cure. Treatment is aimed at providing support while the body fights off and eliminates the virus.

Supportive care may include:

  • Bed rest—Your body will need rest while you recover from your illness.
  • Hydrate—Drink plenty of beverages throughout the day. This will help to replace fluids, sugars, and salts lost during the illness. If you are unable to drink enough, you may need to receive intravenous fluids.
  • Paracetamol/Acetaminophen may be recommended to treat pain and fever. Aspirin or nonsteroidal anti-inflammatory drugs (NSAIDs) are NOT recommended. Talk to your doctor about any medications you are taking.

How to prevent dengue fever?

  • Better protect your location by insect screens or live with air-conditioned.
  • Cover your skin. Wear long-sleeved shirts and pants, and socks and shoes.
  • Use insect repellents on your skin and your clothing. Look for repellents that contain DEET (diethyltoluamide).
  • Use proper mosquito netting during any rest. Look for netting treated with insecticide.
  • Stay inside or take extra precautions in the early morning, late afternoon, and early evening. Mosquitoes are most likely to bite during these times.
  • Do not leave standing water in buckets, flowers pots, or other containers around the house. Mosquitoes breed in standing water.

Vaccines are under development, but are not currently available.