Dengue fever

Causative agents

Dengue fever (DF) is caused by any of four closely related viruses, or serotypes: dengue 1-4. Infection with one serotype does not protect against the others, and sequential infections put people at greater risk for dengue hemorraghic fever (DHF) and dengue shock syndrome (DSS).

Statistics

The World Health Organization (WHO) estimates that 100 million infections occur yearly, including 500,000 DHF cases and 22,000 deaths, mostly among children. Today about 2.5 billion people, or 40% of the world’s population, live in areas where there is a risk of dengue transmission.

Nearly all dengue cases reported in the 48 continental states were acquired elsewhere by travelers or immigrants.

Modes of Transmission

The viruses are transmitted to humans by the bite of an infected mosquito. In the Western Hemisphere, the Aedes aegypti mosquito is the most important transmitter or vector of dengue viruses, although a 2001 outbreak in Hawaii was transmitted by Aedes albopictus. Dengue can also be transmitted in organ transplants or blood transfusions from infected donors, and there is evidence of transmission from an infected pregnant mother to her fetus.

Methods of diagnosis

Serology and polymerase chain reaction (PCR) studies are available to confirm the diagnosis of dengue if clinically indicated. Real-time PCR is the most effective way to identify the virus early, prior to the onset of symptoms.

Annotated Bibliography

1. Department of Health and Human Services, Centers for Disease Control and Prevention, Dengue, Dengue Facts, Epidemiology. http://www.cdc.gov/dengue/epidemiology/index.html

Items of Interest

International Products

Cooperative Diagnostics provides a variety of real-time PCR tests for infectious diseases around the world. Follow the links below to access resources for international products: