Dengue fever, also known as Dengue Hemorrhagic Fever (DHF), is a mosquito-borne viral disease caused by the dengue virus (DENV). It is transmitted to humans through the bite of infected Aedes mosquitoes, primarily Aedes aegypti. Dengue fever is a significant public health concern in tropical and subtropical regions, including Southeast Asia, South America, and parts of Africa.

Causes and Transmission

Dengue fever is caused by four distinct serotypes of the dengue virus: DENV-1, DENV-2, DENV-3, slot and DENV-4. A person infected with one serotype gains immunity to that serotype but remains susceptible to the others. Subsequent infections with different serotypes increase the risk of severe dengue, also known as Dengue Hemorrhagic Fever (DHF) or Dengue Shock Syndrome (DSS).

The virus is transmitted when an infected Aedes mosquito bites a person, injecting the virus into their bloodstream. These mosquitoes are most active during the early morning and late afternoon.

Symptoms of Dengue Fever

Symptoms of dengue fever usually develop 4–10 days after a mosquito bite and can range from mild to severe. Common symptoms include:

• High fever (above 40°C or 104°F).
• Severe headache.
• Pain behind the eyes (retro-orbital pain).
• Muscle and joint pain (often referred to as "breakbone fever").
• Skin rash.
• Nausea and vomiting.
• Mild bleeding, such as nosebleeds or gum bleeding.

In severe cases (DHF or DSS), symptoms may include:

• Persistent vomiting.
• Severe abdominal pain.
• Difficulty breathing.
• Bleeding under the skin or in internal organs.
• Sudden drop in blood pressure, leading to shock.

Severe dengue is a medical emergency and requires immediate treatment to prevent fatal outcomes.

Risk Factors

Certain factors increase the risk of contracting dengue fever or developing severe complications, such as:

• Living in or traveling to areas where dengue is endemic.
• Repeated infections with different dengue serotypes.
• Young children, pregnant women, and individuals with weakened immune systems are more vulnerable to severe dengue.

Diagnosis and Treatment

Dengue fever is diagnosed through blood tests that detect the virus or antibodies. Tests such as NS1 antigen detection and PCR are commonly used for early diagnosis.

There is no specific antiviral treatment for dengue. Management focuses on relieving symptoms and preventing complications:

• Hydration: Drinking plenty of fluids is critical to prevent dehydration caused by fever and vomiting.
• Pain Relief: Paracetamol is recommended for reducing fever and pain. Aspirin and ibuprofen should be avoided as they increase the risk of bleeding.
• Hospital Care: Severe dengue requires hospitalization, where patients may receive intravenous fluids, blood transfusions, or oxygen therapy.

Prevention

Preventing dengue fever involves minimizing mosquito exposure and controlling mosquito populations:

1. Avoid Mosquito Bites

   • Use insect repellents containing DEET, picaridin, or IR3535.
   • Wear long-sleeved clothing and pants, especially during peak mosquito activity.
   • Sleep under mosquito nets, even during the day.

2. Eliminate Breeding Sites

   • Remove stagnant water from containers, flower pots, old tires, and other places where mosquitoes lay eggs.
   • Regularly clean water storage tanks and cover them to prevent mosquito access.
   • Use larvicides or biological agents in standing water that cannot be drained.

3. Community Efforts

   • Participate in local mosquito control campaigns, including fogging and environmental cleanups.
   • Educate communities about dengue prevention and early detection.

4. Vaccination

   • A dengue vaccine, Dengvaxia, is available but is recommended only for individuals who have had a prior dengue infection. Vaccination should be guided by a healthcare professional to avoid adverse effects in individuals who have never been exposed to dengue.

Conclusion

Dengue fever is a preventable disease that requires a combination of individual, community, and governmental efforts to control its spread. Early diagnosis and proper management are essential to reduce the risk of severe complications. By adopting preventive measures, such as reducing mosquito breeding sites and protecting against mosquito bites, individuals and communities can play a vital role in combating dengue fever.