Dengue virus

Abstract

Dengue is the most prevalent arthropod-borne virus affecting humans today. The virus group consists of 4 serotypes that manifest with similar symptoms. Dengue causes a spectrum of disease, ranging from a mild febrile illness to a life-threatening dengue hemorrhagic fever. Breeding sites for the mosquitoes that transmit dengue virus have proliferated, partly because of population growth and uncontrolled urbanization in tropical and subtropical countries. Successful vector control programs have also been eliminated, often because of lack of governmental funding. Dengue viruses have evolved rapidly as they have spread worldwide, and genotypes associated with increased virulence have spread across Asia and the Americas. This article describes the virology, epidemiology, clinical manifestations and outcomes, and treatments/vaccines associated with dengue infection.

Fig. 1

The A aegypti mosquito is the most common epidemic vector for spread of dengue virus. It can be identified by the white bands or scale patterns on its legs and thorax.

Fig. 2

World map indicating regions with known risks of dengue infection.

Fig. 3

Reinfestation of A aegypti in the Americas Unfortunately, the success of the eradication campaign was not sustained. Beginning in the early 1970s, it began to be disbanded, and many countries channeled their limited resources into other areas. Consequently, A aegypti began to reinfest the countries from which it had been eradicated. Comparing the 1970 and 2006 maps, the mosquito is seen reestablishing itself throughout Central America and most of South America. As the mosquito has spread, the number and frequency of dengue epidemics have increased, as has dengue hemorrhagic fever activity in the Americas.

Fig. 4

Warning signs of dengue infection.

Fig. 5

Petechial hemorrhages from a dengue infected patient.