Togaviridae: Rubella Virus

Abstract

Disease: Rubella, congenital rubella. Etiologic Agent: Rubella virus, genus Rubivirus of Togaviridae. Clinical Manifestations: Asyptomatic infections are common; fever with rash; lymphadenitis; arthropathy and arthritis in adults. Congenital infection may result in fetal death and spontaneous abortion, live birth of severely malformed infant, an infant with minimal damage, or a healthy infant. Pathology: Primary site of virus replication is the nasopharyngeal mucosa, followed by spread of virus to local lymph nodes and a viremia 7 days after infection. The appearance of a rash may be caused by viral antigen-antibody complexes. During pregnancy, the virus infects the placenta and is then disseminated to all fetal tissues. Laboratory Diagnosis: IgG serology in paired serum specimens; IgM serology in a single serum. IgG serology is in large-scale use for immunity testing. Epidemiology: Worldwide distribution; endemic in temperate climates, with seasonal peaks during spring and early summer. In countries with successful childhood vaccination programs, major epidemics have been prevented.