Understanding Dengue Fever

What is dengue?

dengue symptoms

Dengue is a disease transmitted between people by the mosquitoes Aedes aegypti and Aedes albopictus which are commonly found in subtropical areas all around the world. The most common areas for dengue outbreaks are regions of South East Asia, the Western Pacific Islands and also Latin America and the Caribbean.

Symptoms generally start to show between 4 to 7days after being bitten by the infected mosquito and usually last 3 to 10 days.

Around the fifth day when there is a large amount of dengue in the blood, if a person is bitten by another mosquito it will become infected with the virus. Once the mosquito has ingested the infected blood the virus will incubate for 8 to 12 days and then it can be transmitted to other humans. The mosquito is then infected for the remainder of its life, usually days to weeks.


In very rare instances dengue may be spread by organ transplants or blood transfusions from infected donors, and there is some evidence it is able to be transmitted from an infected mother to her fetus


The Three Phases of Dengue

Dengue is divided into three phases: febrile, critical, and recovery.

Dengue Febrile Phase

This stage includes a fever up to 41°C and severe head pain, which can last for 2 to 7 days.

Dengue Critical Phase

The fever will drop but during this time blood vessels begin to leak plasma which can lead to fluid accumulating in the chest and the restriction of blood flow to important organs – this phase generally lasts for 1 to 2 days. The critical phase carries the highest risk of death from the disease

Dengue Recovery Stage

The recovery stage is characterized by a sudden improvement in the patient. This stage may include symptoms such as:

  • Decreased heart rate
  • Itching
  • Peeling skin
  • Decreased consciousness


The stages may vary, in order to avoid dangerous complications it is important to treat the disease as early as possible. If you live in a high risk area for dengue and you or a loved one come down with any of the symptoms see your doctor immediately.

Symptoms Of Dengue Fever

General symptoms include 2 or more of these:

  • High fever
  • Severe headache
  • Pain behind the eyes
  • Joint pain
  • Muscular pains and/or bone pain
  • Rash
  • Nausea and vomiting


Younger children, and those infected for the first time generally have milder symptoms than older children and adults, and many people may not experience any symptoms at all.


In a small amount of cases the disease can develop into dengue hemorrhagic fever, a life threatening complication, or dengue shock syndrome.

Dengue Hemorrhagic Fever (DHF)

Dengue Hemorrhagic Fever is characterized by:

Dengue hemorrhagic fever usually begins with a sudden rise in temperature along with flu like symptoms and facial flushing (red face). The fever generally lasts for 2 to 7 days and may be as high as 41°C. The person may also experience other complications such as convulsions.

Dengue Shock Syndrome (DSS)

The Dengue Shock Syndrome (DSS) is characterized by:

  • Tiny red spots on the skin (petechiae)
  • Large patchy areas of blood under the skin (ecchymoses)
  • Bleeding from minor injuries


petechiae signsEcchymoses signs

This Is Important

After 3 to 7 days the fever will begin to drop, although you may believe that this is a sign of recovery it is actually the most critical time that needs a high level of vigilance.

If any of the following occur call an ambulance or go to the nearest emergency room/hospital IMMEDIATELY.

  • Persistent vomiting or abdominal pain
  • Vomiting blood
  • Red spots or patchy skin (petechiae)
  • Bleeding from the nose and/or gums
  • Black, tarry feces (poo)
  • Irritability or drowsiness
  • Pale, cold, clammy skin
  • Breathing difficulties

Dengue Fever Treatment

  • There is no cure or vaccinations for dengue

General treatment for dengue fever:

  • Drink plenty of fluids to stop dehydration
  • Do not take aspirin (acetylsalicylic acid), or any drug which contains aspirin. Do not take non-steroidal anti-inflammatory drugs such as ibuprofen. (All of these drugs stop your blood from clotting effectively, increasing the severity and duration of bleeds)
  • Control fever with acetaminophen and/or a cool sponge
  • Take all precautions to avoid further mosquito bites to reduce the risk of further transmission


If the symptoms become severe, or you have any concerns about anything, go to the nearest emergency room immediately. Intensive care monitoring may be required.


How To Prevent Dengue Infection

The best way to prevent dengue is to avoid mosquito bites by:

  • Removing all places around the home where the mosquito can lay her eggs – Any type of open container that can hold water such as pet watering containers, flower vases, or garden plant dishes.
  • Using mosquito repellent, indoors and outdoors
  • Wearing long pants, long sleeves and a hat
  • Using permethrin-treated clothing and other gear such as socks, boots, hats and even tents. If you don’t want to buy treated clothing you can treat your own clothes yourself.
  • Checking all window screens for holes

Other tips from the Environmental Protection Agency (EPA)

EPA approved mosquito repellents