Dengue Fever: Causes, Symptoms and Prevention
Dengue fever is a mosquito-borne viral infection that causes flu-like illness and can develop into severe dengue, which can be fatal. It is most prevalent in tropical and subtropical regions, especially in urban and semi-urban areas.
Causes
Dengue fever is caused by the dengue virus (DENV), which has four distinct serotypes: DENV-1, DENV-2, DENV-3, and DENV-4. The primary vectors are Aedes aegypti and Aedes albopictus mosquitoes. These mosquitoes become infected when they bite a person already infected with the virus. Once infected, the mosquito can transmit the virus to other humans through bites.
Symptoms typically appear 4-10 days after being bitten by an infected mosquito and last for 2-7 days. They can range from mild to severe and include:
- 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, appearing 2-5 days after the onset of fever
- Mild bleeding (such as nosebleeds, gum bleeding, or easy bruising)
In some cases, the disease can progress to severe dengue, also known as dengue hemorrhagic fever or dengue shock syndrome, characterized by:
- Severe abdominal pain
- Persistent vomiting
- Rapid breathing
- Bleeding gums
- Fatigue and restlessness
- Blood in vomit or stool
- Pale, cold, clammy skin
Diagnosis of dengue fever involves a combination of clinical symptoms and laboratory tests:
- Clinical evaluation: Assessment of symptoms and recent travel history to dengue-endemic areas.
- Laboratory tests: Blood tests to detect the virus or antibodies. These include:
- PCR (polymerase chain reaction) tests to identify the presence of viral RNA.
- NS1 antigen test to detect the dengue virus non-structural protein 1.
- IgM and IgG antibody tests to identify recent or past infections.
Treatment
There is no specific antiviral treatment for dengue fever. Management focuses on supportive care to alleviate symptoms:
- Hydration: Maintaining proper fluid intake to prevent dehydration.
- Fever and pain relief: Acetaminophen (paracetamol) is recommended. Avoid aspirin and non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen due to the risk of bleeding.
- Monitoring: Close monitoring of severe cases for signs of complications, such as shock or severe bleeding, which may require hospitalization.
Prevention
Preventing dengue fever involves controlling mosquito populations and avoiding mosquito bites:
- Eliminate mosquito breeding sites: Remove standing water from containers, gutters, and other areas where mosquitoes can breed.
- Use mosquito repellent: Apply insect repellent on exposed skin and clothing.
- Wear protective clothing: Wear long-sleeved shirts, long pants, socks, and shoes.
- Use mosquito nets: Sleep under mosquito nets, especially in areas with high mosquito activity.
- Install screens: Use window and door screens to keep mosquitoes out.
- Community efforts: Participate in community-wide mosquito control programs.
Vaccination: Dengvaxia is the only approved vaccine for dengue fever and is recommended for individuals who have previously been infected with the virus. It is not widely available in all countries and is subject to specific guidelines and eligibility criteria.
Conclusion
Dengue fever is a significant public health concern in many parts of the world. Understanding its causes, recognizing symptoms early, and taking preventive measures are crucial in managing and reducing the impact of this disease. While there is no specific treatment for dengue, supportive care and vigilance in preventing mosquito bites can help mitigate its effects.
