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Dengue Fever

What is dengue fever?

Dengue fever is caused by a virus that is spread through the bite of an infected mosquito.  The disease has been identified in the Southeastern United States. It is common in tropical and subtropical areas such as the Caribbean, Central America, South America and parts of Southeast Asia and Africa. Cases in Boston are rare and are most common in people who have travelled to a high-risk area.

Who gets dengue fever?

Dengue fever can occur in persons of any age and is more likely to occur in persons who have recently traveled to affected areas.  The disease is usually milder in children than adults.

How is dengue fever spread?

Dengue fever is spread through the bite of an infected mosquito (Aedes aegypti mosquito).  The mosquito becomes infected with dengue virus when it bites a person who has dengue virus in their blood.  It cannot spread from one person to another. 

What are the symptoms of dengue fever?

Dengue fever usually starts suddenly with a high fever, severe headache, pain behind the eyes and joint, bone and muscle pain.  A rash on the feet or legs usually appears 3 to 4 days after the start of the fever.

A more severe form of the illness, called dengue hemorrhagic fever (DHF), can start with a fever for 2 to 7 days followed by vomiting, difficulty breathing and stomach pain.  This is followed by easy bruising, bleeding of the nose or gums, and possibly internal bleeding.  If untreated, this illness can be very serious. 

How soon do symptoms occur?

Dengue fever may occur 3 to 14 days after a bite from an infected mosquito (usually within 4 to 7 days).

Can a person get dengue fever again?

There are 4 different types of dengue fever virus.  A person is only protected against the type of dengue fever virus they have been infected with and will not gain protection from the other types of dengue fever virus.  Therefore, a person could get dengue fever 4 times.

What is the treatment for dengue fever?

There is no specific treatment for dengue fever; however, those with dengue fever should get plenty of rest, drink plenty of fluids and if they feel worse 24 after their fever goes away, they should see a healthcare provider immediately.  If a person thinks they have dengue fever, they can take medication such as acetaminophen (Tylenol ┬«) for the pain but should avoid aspirin.  

How can I prevent dengue fever?

There is no vaccine for dengue fever. The best way to prevent dengue fever is to limit your exposure to mosquitoes and their breeding areas by using mosquito repellent, mosquito netting, and wearing a long-sleeved shirt and pants when traveling to affected areas.  Mosquitoes that have dengue fever tend to live indoors and are often found in dark, cool places.  The risk of being bitten by this type of mosquito is highest during the early morning and several hours after daybreak, and in the late afternoon several hours before sunset.  Containers that collect water should be covered or water should be properly emptied at least weekly to prevent mosquitoes from breeding.

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