Dengue fever is an infectious disease carried by mosquitoes and caused by any of four related dengue viruses. This disease used to be called “break-bone fever” because it sometimes causes severe joint and muscle pain that feels like bones are breaking.
Dengue fever of multiple types is found in most countries of the tropics and subtropics particularly during and after rainy season. It has been seen repeatedly in Texas and Hawaii in this country.
The World Health Organization (WHO) estimate 100 million cases annually, this includes 100-200 cases reported to the Centers for Disease Control and Prevention (CDC), mostly in people that have traveled abroad.
In recent years there have been increased amounts of epidemics in many parts of the world.
There are four types of dengue virus: DEN-1, DEN-2, DEN-3 and DEN-4.
People get the dengue virus from the bite of an infected Aedes mosquito. It is not contagious from person to person.
There are three types of dengue fever in order of less severe to most: the typical uncomplicated dengue fever, dengue hemorrhagic fever (DHS) and dengue shock syndrome (DSS).
The symptoms of classic dengue usually start within a week after being infected. They include very high fever, up to 105Â°F, severe headache, pain behind the eye, severe joint and muscle pain, nausea and vomiting and a rash.
In cases of DHF and DSS, all four types can be the cause in descending order of frequency; type 2, 3, 4 and 1.
There is evidence that types 2 and 4 need to be secondary infection to cause DHF, while primary infection with types 1 and 3 can cause DHF.
Symptoms of DHF include all the symptoms of classic dengue plus severe damage to the blood vessels. Bleeding from the nose, gums or under the skin are common. This form of dengue can be fatal.
Symptoms of DSS include all of the above symptoms plus; fluid leaking outside of blood vessels, massive bleeding and shock. This form of the disease usually happens in children experiencing their second infection.
Two-third of all fatalities occurs among children.
Diagnosis of the disease is often through typical signs and symptoms. Lab tests can be useful. Detection of the virus in acute phase serum within 5 days of onset or specific antibodies in convalescent serum obtained 6 days after onset of illness.
There is no treatment for dengue, just treat the symptoms. Persons who think they have dengue should use analgesics (pain relievers) with acetaminophen and avoid those containing aspirin. They should also rest, drink plenty of fluids, and consult a physician.
There is not a vaccine for dengue fever. The CDC recommends the following preventive measures:
The best preventive measure for residents living in areas infested with Aedes mosquito is to eliminate the places where the mosquito lays her eggs, primarily artificial containers that hold water.
For travelers to areas with dengue, as well as people living in areas with dengue, the risk of being bitten by mosquitoes indoors is reduced by utilization of air conditioning or windows and doors that are screened.
Proper application of mosquito repellents containing 20% to 30% DEET as the active ingredient on exposed skin and clothing decreases the risk of being bitten by mosquitoes.
The risk of dengue infection for international travelers appears to be small, unless an epidemic is in progress.