Clinical Information

Clinical Utility

This assay aids in the diagnosis of infection/exposure to roseola infantum and other HHV-6 infections. This assay may also be useful in the diagnosis of chronic fatigue syndrome.

Clinical Disease

HHV-6 is the causative agent of roseola infantum. Roseola is characterized by the abrupt onset of a high fever which is followed in 2-4 days by erythematous maculopapular rash that lasts for 1-2 days. Roseola lesions are macular or papular and never become vesicular like the lesions associated with VZV or HSV. Lesions typically appear on the neck and back and then spread to the abdomen and thighs. The syndrome is self-limiting, but convulsions associated with high fever can cause permanent neurologic injury. Atypical roseola can occur in the absence of rash (1).

Epidemiology

HHV-6 infections are common, and viruses have been found throughout the world. HHV-6 infections can occur in all age groups. Infection is most often acquired before three years of age. HHV-6 is the causative agent of roseola in children. Roseola is a common infection of infancy, and the peak incidence of roseola occurs between the ages of 6 and 18 months. Infants less than 6 months are thought to be protected by maternal antibodies. Adults who become infected are often only mildly symptomatic (1).

Incubation Period

5-15 days (1).

Transmission

Transmission of HHV-6 is poorly understood. It is thought that the virus is transmitted after contact with oral secretions (1).