Dengue Fever

Dengue Fever - What it is

What is dengue fever?

Dengue fever is an illness caused by dengue virus, which is carried and spread by the Aedes mosquitoes. These viruses cause the body to bleed easily and may affect other organ systems.

Dengue Fever - Symptoms

What are the signs and symptoms of dengue fever?

The common symptoms are

• Fever
• Headache
• Muscle and joint aches.
• Rash-different types of rash which may itch and appears a few days after the onset of fever.
• Bleeding tendency- from nose, gums or other parts of the body due to low platelets. Platelets are one of the blood components which help to clot and prevent excessive bleeding. Normal levels range from 150,000 to 450,000 per millilitre.
• Bruises from minor knocks and bumps.
  

Sometimes, dengue infection can present in a more serious form, known as Dengue Hemorrhagic Fever (DHF). 

Serious complications can occur resulting in:

• Widespread bleeding.
  
• Low blood pressure or shock due to bleeding or leaking blood vessels.
• Organ failure.
• Death (The risk of dying from dengue complications is very low; less than one to five percent if supportive treatment is given early).

Dengue Fever - Causes and Risk Factors

Can you or your child be managed at home?

Majority of the cases are mild, self-limiting and requires no hospitalisation.

Assessment

• Blood test is done daily to assess the platelet level and concentration (as it can be normal during the first few days of fever).
• Blood test can also be done at the polyclinics or general practitioner (GP) clinics.
  

There is no antibiotic or anti-viral medication for dengue fever. The treatment is mainly supportive and for relief of symptoms. The main components of management of dengue fever are:

Fluid or water replacement

• Children about one year old or weigh more than 10kg should drink at least one litre of fluids a day.
• Children who weigh more than 40kg or adult should drink at least two litres of fluids a day.
  This is because
  - Fever increases water loss from your body.
  - Dengue fever causes the blood vessels to be leaky and increases water loss f rom the blood circulation.
  

Symptom relief and fever control

• Painkillers (eg. paracetamol) may be given to relieve pain and control fever.
• Avoid aspirin (or other medications such as ibuprofen and diclofenac suppositories that affect the platelet functions) as it can increase the risk of bleeding.
• Medications may be given for nausea and vomiting.
  

Bleeding prevention and control

• Rest in bed and reduce activities li ke running around and avoiding sports to reduce the risk of falls and injury.
  
• Avoid brushing your teeth and traumatising your nose (eg. from digging) when your platelet counts drop below normal levels.
• If superficial bleeding occurs, apply firm pressure to the bleeding point for several minutes. For nosebleeds, use fingers to apply pressure to the upper part of the nasal bridge (by squeezing) and lean forward.
  

Note: Seek medical attention whenever there is evidence of bleeding.

When do you or your child need to return to the hospital?

• Blood platelet count less than 80,000.
• Bleeding from the nose or gums without any injury.
• Unwell (lethargic, drowsy or have breathing difficulty).
  
• Vomiting or poor feeding/drinking.
• Severe abdominal pain and giddiness.
  

Note: Hospitalisation may be considered when you or your child is presented with the above conditions.

Dengue Fever - Diagnosis

Assessment, observation and treatment during hospitalisation

• Blood tests are done daily to assess the platelet level and blood concentration.
• Vital signs (eg. pulse rate or blood pressure) are monitored to detect any potential complications of dengue fever.
• Intravenous fluid (drip) may be required.
• Platelets or blood transfusion may be given if the spontaneous bleeding.
• Admission and treatment in high dependency or intensive care unit for artificial ventilation, blood pressure support and other measures may be necessary for patients who are critically ill.
  

When can you or your child go home?

Current hospital guidelines al low children who are well and have a rising platelet trend or platelet above 80,000 to be discharged. For adults, our doctors will assess each patient and advice on suitability for discharge.

After discharge, a repeat blood test (details included with discharge letter) should be done as and when instructed by your medical team.

A further week of rest at home with no strenuous physical activities may be advised as some patients may feel very tired.

Dengue Fever - Post-surgery care

Can you or your child spread dengue to others?

No. Dengue fever is not transmitted by direct spread from one person to another. It is transmitted by infected mosquito bites. Hence, persons in the same vicinity may come down with dengue fever.

Can you or your child be infected again?

Yes. There are four strains of dengue viruses. Infection with one strain will provide protection against only that particular strain. Future infection by other strains is possible. Currently, there is no vaccine available for dengue fever.

How to reduce the chances of being infected by dengue fever?

Singapore is in the tropical region where Aedes aegypti mosquitoes live. The best prevention is to get rid of mosquito breeding places: 

• Change water in vases or bowls (including pet water containers) on alternate days.
• Remove water from flowerpot plates on alternate days.
• Turn over all water storage containers.
• Cover bamboo pole holders when not in use.
• Cover rarely used gully traps.
• Add prescribed amount of Temephos sand granular insecticide in roof gutters at least one a month.
• Cover toilet bowls and floor traps when away from home for a few or more days.
• Fit all floor traps with anti-mosquito valves.
  

Air-conditioning or window/doors with mosquitoes screen can reduce the risk of being bitten by mosquitoes.

Using mosquito repellents containing DEET as the active ingredient on exposed skin and clothing can also decrease the risk of being bitten by mosquitoes.

However, it is important to note

• Children below two months old should avoid DEET mosquito repellent.
• Children below three years old should avoid eucalyptus oil.
• Children above two months old should use mosquito repellent in low er concentration of DEET between seven to 20%.
• Pregnant women should reduce the usage of DEET mosquito repellent and apply on clothing instead.
• Mosquito repellent with DEET in concentration between 20 to 30% is only suitable for adults.