Dengue is a mosquito-borne viral infection that causes fever, generalized body aches, and, if severe, external and internal bleeding (called dengue hemorrhagic fever).
About 50 to 100 million cases of dengue and about 20,000 deaths occur worldwide.
Symptoms vary in severity but may include fever, chills, a severe headache, pain when the eyes are moved, extreme fatigue, and severe generalized body aches.
A more severe form, called dengue hemorrhagic fever, may cause bleeding from the nose, mouth, gastrointestinal tract, and puncture wounds.
To diagnose dengue, doctors do blood tests to check for the virus or antibodies to the virus.
A vaccine is available in Mexico, Brazil, Thailand, and some other countries (not in the United States), but use is restricted to people who have previously had dengue.
Treatment of dengue focuses on relieving symptoms and, for dengue hemorrhagic fever, fluids and blood products given intravenously.
Dengue is common in the tropics and subtropics worldwide. It is most common in Southeast Asia but has become more common in Central and South America and other countries. It has occurred in the Caribbean (including Puerto Rico and the U.S. Virgin Islands), in Oceania, and in the Indian subcontinent. The infection is caused by a flavivirus that is spread by mosquitoes.
Many factors have contributed to the spread of dengue:
Climate change, resulting in more areas where the mosquito can live
Spread of the mosquito that carries the virus
Lack of an effective vaccine
Each year, about 50 to 100 million cases and about 20,000 deaths occur worldwide. However, in the United States, only about 100 to 200 cases occur yearly, nearly all brought in by travelers returning from affected areas. If these travelers live in an area with Aedes mosquitoes, the mosquitoes may bite them, then bite other people living in the area. The dengue virus is thus spread to other people (called local transmission). A few cases of locally transmitted dengue have occurred in Hawaii, Florida, and Texas.
There are four types of dengue virus (serotypes). Infection with one of the serotypes protects against infection with that serotype for a long time but provides only limited and temporary protection against infection with the other serotypes.
