What is Dengue fever?
Dengue (pronounced DEN-gee) fever is a human virus transmitted by the Aedes aegypti mosquitoes which are very common in tropical and subtropical areas of the world. The World Health Organization has ranked this virus the most rapidly spreading mosquito-borne viral disease. The transmission cycle of dengue is from human, to mosquito, to human.
When a mosquito bites a person who is infected with dengue, it takes approximately 10-14 days for that mosquito to transmit the virus to another person. Meanwhile, the virus replicates within the mosquito until is reaches its salivary glands. The virus is then injected via the mosquito’s saliva into another human when it bites.
There are four different specific serotypes (strains) of dengue fever (DV-1, -2, -3, -4), and prior infection of one strain will make someone more susceptible to developing a more serious form of the virus, dengue haemorrhagic fever (DHF), if subsequent infections occur.
Signs and Symptoms of Dengue and Dengue Haemorrhagic Fever:
Dengue fever is a self-limiting virus, and will resolve on its own. However, DHF has a mortality rate of up to 50% if left untreated.
Following a dengue infection, there is an incubation period of up to 7 days. Some people remain asymptomatic during this time, however most will experience classic symptoms of dengue fever. The symptoms may include:
- Sudden onset of fever
- Rash and flushing
- Retro-orbital pain (pain behind the eyes)
- Severe myalgia (muscle pain): back, arms, legs and arthralgia (joint pain)
- Loss of appetite, abdominal pain, nausea and/or vomiting
- General malaise
- Bleeding gums/nose
- Low platelet count and petechiae rash
Dengue Haemorrhagic Fever is similar to Dengue fever, however after the initial period of febrile onset, it progresses to become more serious. Signs of plasma leakage develops, along with haemorrhages (hematuria, gastrointestinal bleeding) and symptoms of circulatory failure. Thi