Dengue fever is a mosquito-borne viral infection caused by the dengue virus. It is mainly spread through the bite of infected Aedes mosquitoes, particularly Aedes aegypti and Aedes albopictus. Dengue is common in tropical and subtropical regions, especially in areas where mosquitoes can breed easily in warm and humid conditions.
Dengue can range from a mild illness to a serious infection that may become life-threatening. Many people recover within a week or two, but some develop severe dengue, which can cause internal bleeding, dangerously low blood pressure, organ problems, and shock.
There are four closely related dengue virus types, commonly referred to as DENV-1, DENV-2, DENV-3, and DENV-4. Infection with one type generally provides long-term protection against that same type, but a person can become infected with another dengue virus type later.
Dengue fever is not usually spread directly from one person to another. An infected mosquito becomes infected when it bites a person who has dengue virus in their blood. The mosquito can then transmit the virus when it bites another person.
The disease often begins suddenly with a high fever. Other common symptoms include severe headache, pain behind the eyes, muscle and joint pain, nausea, vomiting, weakness, and skin rash.
Some people develop mild dengue without complications, while others may become seriously ill, particularly around the time their fever begins to improve. This is why monitoring symptoms is important even when the temperature starts falling.
Dengue is diagnosed using a combination of symptoms, medical history, physical examination, and blood tests. Depending on the stage of illness, doctors may use tests that detect dengue virus components or antibodies.
There is no specific antiviral medicine that cures dengue. Treatment mainly involves rest, adequate fluids, monitoring, and appropriate fever or pain control. Severe dengue may require hospitalization and careful management of fluid balance, bleeding, and other complications.
Preventing mosquito bites is one of the most important ways to reduce the spread of dengue.
Dengue fever is caused by the dengue virus, which belongs to the Flavivirus group.
The virus is mainly transmitted through the bite of infected female Aedes mosquitoes.
Aedes aegypti is one of the most important mosquitoes involved in dengue transmission. These mosquitoes can live close to people and often breed in containers holding stagnant water.
Mosquitoes can breed in water collected in buckets, flowerpots, discarded tires, bottles, tanks, containers, and other objects around homes and buildings.
Unlike some mosquitoes that are most active at night, Aedes mosquitoes can bite during the day, particularly during the morning and later afternoon.
When a mosquito bites a person who has dengue virus in their bloodstream, the mosquito can acquire the virus.
The virus then develops inside the mosquito. After the mosquito becomes infectious, it can transmit dengue when it bites another person.
Dengue can spread rapidly in communities when infected mosquitoes are abundant.
There are four major dengue virus types. A person can be infected more than once because previous infection does not provide complete protection against all types.
A second dengue infection with a different virus type may be associated with a higher risk of severe disease in some people.
Dengue is not normally spread through casual contact such as shaking hands, hugging, sharing food, coughing, or sitting near an infected person.
In uncommon situations, dengue may be transmitted through blood products, organ transplantation, or from an infected mother to her baby around pregnancy or childbirth.
The risk of dengue increases in warm and humid environments where Aedes mosquitoes can reproduce easily.
Poor management of standing water can increase mosquito populations and contribute to outbreaks.
The best way to prevent dengue is to avoid mosquito bites and reduce mosquito breeding sites.
Because Aedes mosquitoes can bite during the daytime, mosquito protection should not be limited to nighttime.
Use mosquito repellents on exposed skin according to the product's instructions. Repellents containing recognized active ingredients can provide protection against mosquito bites.
Wear long-sleeved shirts, long trousers, socks, and other clothing that reduces exposed skin when practical.
Use window and door screens to prevent mosquitoes from entering homes.
Air conditioning can also reduce mosquito exposure when available.
Use mosquito nets when appropriate, particularly for people sleeping during the day, babies, young children, or people who are sick and may be resting for long periods.
The most important community prevention measure is eliminating standing water.
Empty and clean containers that collect water around homes regularly.
Cover water storage tanks and containers tightly.
Remove discarded tires, bottles, cans, plastic containers, and other objects that can collect rainwater.
Keep flowerpot trays and similar containers free of stagnant water.
Clean gutters and drains so water does not remain trapped.
Community mosquito-control programs can also help reduce mosquito populations during outbreaks.
People who have dengue should also try to avoid mosquito bites during the early stage of illness. An infected mosquito can acquire the virus from the person's blood and later spread it to others.
Dengue prevention therefore protects both the individual and the wider community.
Travelers visiting dengue-risk areas should use mosquito repellent, wear protective clothing, and stay in accommodation with screens or air conditioning where possible.
People should seek medical advice if they develop a high fever after living in or traveling to an area where dengue is common.
Dengue fever is a common but potentially serious viral infection. Most people recover with appropriate supportive care, but severe dengue can become life-threatening if warning signs are missed.
Early medical evaluation is important, particularly when a person has a high fever accompanied by severe headache, body aches, vomiting, rash, or unusual bleeding.
Patients should pay close attention to warning signs even if the fever begins to improve. Severe abdominal pain, repeated vomiting, bleeding, breathing difficulty, extreme weakness, confusion, fainting, or reduced urine output require urgent medical care.
There is no substitute for mosquito-control measures in areas where dengue is common. Removing stagnant water, using mosquito repellents, wearing protective clothing, and preventing mosquitoes from entering homes can significantly reduce exposure.
Dengue prevention works best when individuals, households, and communities all participate. With early diagnosis, careful monitoring, proper hydration, and timely treatment of complications, most people with dengue can recover successfully.
Medical Disclaimer: This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider. In an emergency, call emergency services immediately.