Dengue

What causes Dengue?

Dengue is caused by a viral infection transmitted to humans through the bite of infected mosquitoes, primarily *Aedes aegypti* mosquitoes.

What is the estimated number of dengue infections worldwide annually?

It is estimated that 100-400 million dengue infections occur worldwide each year.

In which areas is Dengue most commonly found?

Dengue is most commonly found in tropical and subtropical climates, mainly in urban and semi-urban areas.

What percentage of people with dengue have mild or no symptoms?

Most people (around 80%) with dengue have mild or no symptoms and recover in 1-2 weeks.

What are the common symptoms of Dengue?

Symptoms include high fever (40°C/104°F), severe headache, pain behind the eyes, muscle and joint pains, nausea, vomiting, swollen glands, and a rash.

What are the signs of severe dengue?

Severe dengue symptoms include severe abdominal pain, persistent vomiting, rapid breathing, bleeding gums or nose, fatigue, blood in vomit or stool, and pale, cold skin.

How long does it typically take for symptoms to appear after dengue infection?

Symptoms typically appear 4-10 days after infection and last for 2-7 days.

How is dengue treated?

There is no specific treatment for dengue. Pain medicines like acetaminophen (paracetamol) are used, while non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen and aspirin should be avoided.

What was the highest number of dengue cases reported globally?

The highest number of dengue cases was recorded in 2023, with over 6.5 million cases and more than 7,300 deaths.

What are the main vectors for dengue transmission?

The primary vector for dengue transmission is the *Aedes aegypti* mosquito, though *Aedes albopictus* (tiger mosquito) has also contributed to outbreaks in Europe in 2023.

How long can mosquitoes transmit the dengue virus after being infected?

Once infected, mosquitoes can transmit the dengue virus for the rest of their life.

What risk factors increase the likelihood of severe dengue?

Previous infection with dengue virus, urbanization, and high population density increase the risk of severe dengue.

What are some ways to reduce the risk of dengue infection?

Prevent mosquito bites by using insect repellents (DEET, Picaridin), wearing long sleeves, using mosquito nets, and using mosquito coils.

What is one of the vaccines available for dengue?

The QDenga vaccine has been approved and licensed in some countries and is recommended for ages 6-16 years in high transmission areas.

How does the WHO respond to dengue outbreaks?

WHO supports countries with outbreak confirmation, technical guidance, vector control, training, and the development of evidence-based strategies and new tools.

What is the link between climate change and dengue transmission?

Climate change, especially increased temperatures, rainfall, and humidity, can expand the range and increase the spread of mosquitoes that transmit dengue.