The study, which appears online this week in the journal Emerging Infectious Diseases, a publication of the U.S. Centers for Disease Control and Prevention, used viral genetics to comprehensively demonstrate the global movement of a virus associated with severe disease.
The particular dengue virus subtype has been responsible for epidemics of dengue hemorrhagic fever in Sri Lanka, East Africa and Latin America.
The illness is characterized by internal hemorrhage that sometimes leads to shock - a drop in blood pressure and failure of blood cells to meet the metabolic demands of the body. It is a leading cause of death among children in Southeast Asia.
Dengue (pronounced den-GAY) includes four distinct viruses or serotypes, dengue 1 through 4. All are mainly transmitted via the bite of Aedes mosquitoes, two of which, Aedes albopictus and Aedes aegypti, are common in the southeastern United States. Mosquitoes become infected with dengue after taking a blood meal from a dengue-infected person.
People infected with dengue virus develop dengue fever or dengue hemorrhagic fever. Dengue fever is also known as "breakbone disease" because of severe headache and joint pain associated with it.
Dengue hemorrhagic fever is far more serious than the rarely fatal dengue fever. After a short incubation period (one-to-two weeks), the mosquito can transmit the infection to a susceptible person. An infection with any of the four serotypes confers protective lifelong immunity only to that serotype. The risk of developing hemorrhagic dengue appears to be increased among people subsequently infected with a different serotype.
In recent years hemorrhagic dengue has become increasingly prevalent in tropical America.
Contact: Leslie Lang
University of North Carolina School of Medicine