Dengue infection is endemic in tropical and subtropical countries and is highly endemic in this part of the world – Southeast Asia, the so called hot zone.
In the last few months (January – April 2014), there has been an average of 200 cases of Dengue per week notified to the Ministry of Environment, Singapore. This represents a higher than usual incidence, consistent with an ongoing epidemic in this part of the world. In 2013, there were just over 22,000 cases of Dengue notified with a total of 8 deaths up to end December 2013. Children tend to have milder symptoms than adults.
Dengue is caused by an Arbovirus called Dengue virus of which there are 4 strains – Type 1,2,3,4. Infection with a particular strain will confer immunity to that strain but does not confer cross protection to the other strains. Therefore it is possible to have Dengue infection 4 times in a lifetime but this is rare because we have one predominant strain in Singapore and a lesser proportion of a second strain here. Infection is caused by a bite from an infected Aedes mosquito, which is the vector for transmission of Dengue. Very rarely, human to human transmission is reported. The incubation period is 3 – 7 days.
- Fever with muscle aches, headaches
- Reddish rash and sometimes bruising and bleeding into the skin
- Eyeball pain (eye muscle pain)
- Vomiting, diarrhoea and swollen hands and feet
- Bleeding gums,nose bleeding and rarely vomiting blood
- Dengue Fever: usually mild with rash and slightly low platelets
- Dengue Hemorrhagic Fever with more rash, bleeding and lower platelet count as well as fluid leakage into lungs, extremities and abdominal bloating (capillary leak)
- Dengue Shock Syndrome which is the most severe form of Dengue infection resulting in shock, bleeding, very low platelets, multi-organ failure and death.
Your platelet levels are usually in the normal range of between 140 – 440 X 109/L. In Dengue infection, it can drop to a very low level and the patient can start bleeding. Sometimes, they will need a platelet transfusion if there is bleeding. When the platelets have dropped to < 100,000 /ml , daily monitoring is recommended.
Not all Dengue patients need admission to hospital. Most can be managed as outpatient. Some criteria for admission include:
- Dehydration and vomiting requiring intravenous infusion
- Rapidly dropping platelets or low platelets early in the disease
- Bleeding from any site
- Patients with multiple co-morbidities
- Shortness of breath or hypotension (Low blood pressure)
Click here for Appointment