Clinical virology in children.

Virology has become an increasingly important field of medicine in the past decade. Many infectious diseases that were once of unknown etiology can now be linked to the specific viral pathogen. New methods for diagnosing and treating viral diseases are being developed. In addition, antiviral therapy or prophylaxis is available for many of these viral illnesses. This article reviews the basic medical aspects of some viral infections. Human parvovirus B19 causes erythema infectiosum, with the classic "slapped-cheek" rash. Human herpesvirus type 6 is thought to be the cause of roseola infantum, characterized by the familiar macular/maculopapular rash on the trunk and arms. Varicella-zoster virus infection results in chickenpox, which in the future may be prevented by a vaccine. Herpes simplex virus-1 causes up to 90 percent of oral and labial herpes infections. Congenital cytomegalovirus infection results in birth defects. Epstein-Barr virus is the primary cause of mononucleosis. Human papillomavirus causes laryngeal and genital warts. Respiratory syncytial virus is the major cause of lower respiratory tract disease in children. Rotavirus is the common agent in childhood diarrhea.