Dengue fever is a viral illness transmitted by the bite of infected Aedes mosquitoes. It is common in tropical and subtropical regions, where these mosquitoes thrive. Symptoms usually appear 4 to 10 days after being bitten and can include high fever, severe headaches, joint and muscle pain, and rash. Most people recover within a week, but some cases can develop into severe dengue, which can be life-threatening. Preventing dengue involves reducing mosquito populations and avoiding bites, such as using insect repellent and wearing long sleeves. Staying informed about outbreaks in your area is also important for protection.