Worldwide the incidence of dengue infections has increased dramatically over the past several years. With more than one-third of the world’s population living in areas at risk for transmission, dengue infection is a leading cause of illness and death in the tropics and subtropics. International travelers that visit these areas are at increased risk for dengue fever. Many common travel destinations, including most of the Caribbean, Central American, and South American countries, are currently experiencing increases in dengue.
The Florida Department of Health has reported cases of dengue fever acquired in Key West, and the mosquitoes associated with dengue infection (Aedes aegypti and Aedes albopictus) are present in certain areas within Sarasota County.
Following is information about dengue symptoms, risks factors for severe disease and recommendations to help safeguard your health from local, state and federal public health officials monitoring the spread of the virus.
What is the dengue virus?
As many as 100 million people are infected yearly with the dengue virus. Dengue is caused by any one of four related viruses transmitted by mosquitoes. There are not yet any vaccines to prevent infection with dengue virus (DENV) and the most effective protective measures are those that avoid mosquito bites. When infected, early recognition and prompt supportive treatment can substantially lower the risk of developing severe disease.
Dengue Hemorrhagic Fever (DHF) is a more severe form of dengue infection. It can be fatal if unrecognized and not properly treated in a timely manner. DHF is caused by infection with the same viruses that cause dengue fever. With good medical management, mortality due to DHF can be less than 1 percent.
Is this a new virus?
Dengue has emerged as a worldwide problem only since the 1950s. Although dengue rarely occurs in the continental United States, it is currently the most frequent cause of acute febrile illness among returning U.S. travelers from the Caribbean, Central and South America, and Asia. It is widespread throughout the tropics and sub-tropics and an outbreak was recently identified in Key West, Florida.
How is it contracted?
Dengue cannot be spread directly from person to person. The primary method of transmission is through the bite of an infected Aedes aegypti. mosquito. Dengue may also be transmitted from mother to fetus in utero.
What are the symptoms of the disease?
The principal symptoms of dengue fever are high fever, severe headache, severe pain behind the eyes, joint pain, muscle and bone pain, rash, and mild bleeding (e.g., nose or gums bleed, easy bruising). Generally, younger children and those with their first dengue infection have a milder illness than older children and adults.
Dengue hemorrhagic fever is characterized by a fever that lasts from 2 to 7 days, with general signs and symptoms consistent with dengue fever. When the fever declines, symptoms including persistent vomiting, severe abdominal pain, and difficulty breathing, may develop. This marks the beginning of a 24- to 48-hour period when the smallest blood vessels (capillaries) become excessively permeable (“leaky”), allowing the fluid component to escape from the blood vessels into the peritoneum (causing ascites) and pleural cavity (leading to pleural effusions). This may lead to failure of the circulatory system and shock, followed by death, if circulatory failure is not corrected. In addition, the patient with DHF has a low platelet count and hemorrhagic manifestations, tendency to bruise easily or other types of skin hemorrhages, bleeding nose or gums, and possibly internal bleeding.
What is the treatment for dengue?
There is no specific medication for treatment of a dengue infection. People 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. If they feel worse (e.g., develop vomiting and severe abdominal pain) in the first 24 hours after the fever declines, they should go immediately to the hospital for evaluation.
What can be done to reduce the risk of contracting dengue?
There is no vaccine for preventing dengue. The best preventive measure for residents living in areas infested with Ae. aegypti is to eliminate the places where the mosquito lays her eggs, primarily artificial containers that hold water.
Items that collect rainwater or to store water (for example, plastic containers, 55-gallon drums, buckets, or used automobile tires) should be covered or properly discarded. Pet and animal watering containers and vases with fresh flowers should be emptied and cleaned (to remove eggs) at least once a week. This will eliminate the mosquito eggs and larvae and reduce the number of mosquitoes present in these areas.
Using air conditioning or window and door screens reduces the risk of mosquitoes coming indoors. Proper application of mosquito repellents containing 20-30 percent DEET as the active ingredient on exposed skin and clothing decreases the risk of being bitten by mosquitoes.
Centers for Disease Control:
FL DOH dengue and general arbovirus information: