Dengue
Dengue is a mosquito-borne viral illness that can cause high fever and severe aches, and in some cases can progress to dangerous bleeding, shock, or organ injury.
What dengue is
Dengue is an illness caused by dengue virus, a flavivirus spread by mosquitoes. Many infections cause no symptoms or mild illness, but dengue can also cause intense fever, pain, rash, and fatigue. A small share of cases become severe and need close medical monitoring.
How mosquitoes spread it
Aedes mosquitoes can pick up dengue virus when they bite a person with virus in the blood. After the virus multiplies inside the mosquito, later bites can infect other people. Aedes mosquitoes often live near people and breed in small containers of standing water, which makes household and neighborhood control important.
Symptoms
Symptoms commonly include sudden fever, severe headache, pain behind the eyes, muscle and joint pain, nausea, vomiting, swollen glands, and rash. Dengue is sometimes called break-bone fever because the aches can be intense. Symptoms overlap with many other infections, so testing and exposure history can matter.
Warning signs and severe dengue
Dengue can worsen as fever begins to fall. Warning signs include severe abdominal pain, persistent vomiting, fluid buildup, bleeding from the nose or gums, blood in vomit or stool, extreme tiredness, restlessness, or difficulty breathing. Severe dengue can cause shock, severe bleeding, or organ damage and is a medical emergency.
Diagnosis
Clinicians consider dengue when someone has fever and lives in or traveled to an area with dengue risk. Testing depends on timing. Early in illness, molecular tests or NS1 antigen tests may detect the virus; antibody tests become more useful after several days. Cross-reactions with other flaviviruses can complicate interpretation.
Treatment
There is no specific antiviral treatment for dengue. Care focuses on fluids, rest, fever and pain control with medicines a clinician says are appropriate, and watching for warning signs. Aspirin and nonsteroidal anti-inflammatory drugs such as ibuprofen are often avoided because they can increase bleeding risk.
Prevention
Prevention focuses on avoiding mosquito bites and reducing mosquito breeding. Useful steps include repellents, long sleeves, window screens, air conditioning, bed nets when needed, and emptying or covering containers that hold water. Community vector control matters because one household cannot control all mosquito movement.
Vaccines and prior infection
Dengue vaccines are more complicated than many vaccines because prior dengue infection can affect future risk. Vaccine recommendations vary by country, age, local transmission, and product. People should follow local public-health guidance rather than assuming dengue vaccination is the same everywhere.
Why it matters
Dengue matters because it is expanding in a world of dense cities, travel, warming temperatures, and adaptable mosquitoes. The disease can look like an ordinary fever at first, but the dangerous period may arrive later, just when someone thinks they are getting better.