Journal of Tropical Diseases & Public Health

Dengue Fever

Dengue Fever is a viral illness caused by the dengue virus, primarily transmitted to humans through the bite of infected Aedes mosquitoes, especially Aedes aegypti. It is endemic in tropical and subtropical regions of the world.

Causes

• Dengue Virus: There are four distinct serotypes of the dengue virus (DEN-1, DEN-2, DEN-3, and DEN-4), which can lead to varying degrees of severity in illness.
• Mosquito Vectors: The primary vectors are the Aedes mosquitoes, which thrive in urban areas and breed in standing water.

Symptoms

Symptoms typically appear 4 to 10 days after the mosquito bite and may include:

• Mild to Moderate Symptoms:
  • High fever (up to 104°F or 40°C)
  • Severe headache
  • Pain behind the eyes
  • Joint and muscle pain
  • Nausea and vomiting
  • Fatigue
  • Skin rash (may appear a few days after the fever)

• Severe Dengue (Dengue Hemorrhagic Fever or Dengue Shock Syndrome):
  • Severe abdominal pain
  • Persistent vomiting
  • Rapid breathing
  • Bleeding gums or nosebleeds
  • Fatigue or restlessness
  • Blood in urine or stool

Diagnosis

Diagnosis is typically based on:

• Clinical Assessment: Evaluation of symptoms and medical history.
• Laboratory Tests:
  • Blood Tests: Complete blood count (CBC) to check for low platelet count.
  • Serological Tests: Detection of antibodies (IgM and IgG) or viral RNA through polymerase chain reaction (PCR).

Treatment

There is no specific antiviral treatment for dengue fever. Management focuses on symptomatic relief:

• Hydration: Increased fluid intake to prevent dehydration.
• Pain Relief: Acetaminophen (Tylenol) is recommended. Non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen and aspirin should be avoided due to bleeding risks.
• Monitoring: Close monitoring for warning signs of severe dengue, particularly during the critical period (3-7 days after symptom onset).

 

Prevention

Preventive measures focus on reducing mosquito exposure:

• Avoid Mosquito Bites:
  • Use insect repellent containing DEET or picaridin.
  • Wear long-sleeved clothing and long pants.
  • Use mosquito nets while sleeping.

• Environmental Management:
  • Eliminate standing water where mosquitoes breed.
  • Use larvicides in water containers.

• Vaccination:
  • The dengue vaccine, Dengvaxia, is approved for individuals aged 9 to 45 years who have had at least one previous dengue infection. Its use should be based on serostatus.

Public Health Implications

• Burden of Disease: Dengue is a significant public health concern in many tropical regions, with millions of cases reported annually.
• Outbreak Preparedness: Timely monitoring, rapid response to outbreaks and community education are essential for controlling the spread.

Global Health Initiatives: International cooperation is vital to address the burden of dengue and develop vaccines and treatments.