CDC Interview: Traveling? Beware Dengue Fever!

Traveling to Latin America, the Caribbean or the Southern part of the United States anytime soon? Beware of dengue fever! A recent outbreak of this potentially deadly disease in Brazil has reinvigorated attention to dengue fever and rightly so says Dr. Lyle Petersen, Director of the Division of Vector-Borne Diseases at the CDC (Center for Disease Control). Dr. Petersen expressed concern at the lack of attention being given to the threat of dengue fever by the media since the spread of the disease has been rapidly growing for the last decade, particularly in the Americas. The media demonstrated far more hysteria over bird flu which is far less prevalent and carries a far less risk of infection to humans here in America than dengue fever.

Dengue fever is transmitted from the vector mosquito to humans and back to the mosquito in a unique vector-host-vector pattern because most mosquito borne diseases have birds as hosts. Humans are the primary host for dengue fever. There are two traditional vectors for the disease: the Aedes Aegypti mosquito and the Aedes Albopicpus mosquito (also known as the Asian Tiger). The Aedes Aegypti, more commonly associated with yellow fever transmission is the most common carrier of the dengue fever virus. This mosquito is a highly effective vector and causes giant outbreaks of dengue like that currently happening in Brazil. Besides Latin America and the Caribbean, they can be found in Mississippi, Alabama, Georgia, Florida, Tennessee, Kentucky, South Carolina, North Carolina, Virginia, New York, Delaware, Maryland and the District of Columbia. Western states include Arkansas, Illinois, Kansas, Louisiana, Missouri, Oklahoma, New Mexico and Texas. Densities are greatest in the Gulf Coast states. Past efforts to eradicate them in the U.S. have failed.

The other vector mosquito which causes smaller outbreaks, Aedes Albopicpus (Asian Tiger) is not native to the U.S. but was imported starting back in 1985 in shipments of used auto tires containing its eggs. This mosquito breeds faster as the temperatures get higher according to Barry Alto, a University of Florida entomology doctoral student and co-author of a study appearing in the Journal of Medical Entomology. "If global warming trends continue, the Asian tiger mosquito may become common in places it's not found today."

"There are two primary reasons for the rapid spread off dengue fever particularly in the Americas," said Dr. Petersen of the CDC. "The first is globalization; people are traveling more. The second is population increases particularly into more urban areas." Last year there were 900,000 cases of dengue fever in the Americas alone. Currently, there is no vaccine for dengue fever but the CDC is close to developing one according to Dr. Petersen.

Dr. Petersen stressed that the biggest risk is to travelers and suggested recommendations for those who might be traveling to areas where Dengue is known to have caused outbreaks. First he recommends you use insect repellent. Second, stay in a hotel that has air conditioning and screens in the windows. "The mosquito more commonly known to spread Dengue, the aedes aegypti is specially adapted to living indoors and to biting humans," he added, "so screens are really important."

Signs and symptoms of dengue fever: Within three days to a week of being infected, the person may experience any of the following alone or in combination: fever, joint and muscle pain, bone pain, severe headache, skin rash, and fatigue. Thereafter, the person often suffers a prolonged period of fatigue that lasts for weeks. In a small percent of people, there is the potential to develop dengue hemorrhagic fever and shock syndrome which can be fatal if not treated. Whether a person develops this depends upon the strain of dengue they have been infected with by the vector. If you notice any of these symptoms following a trip to a known infected area, please consult your physician or the CDC immediately.