The state of the art may have changed since the publication date.
Clinical manifestations vary according to age at presentation.
Incubation period is 4 to 7 weeks. Diagnosis is primarily made with the monospot test but may include throat culture and complete blood count with differential. Cytomegalovirus and human immunodeficiency virus are among the many other conditions that may present initially as infectious mononucleosis. Always watch for outdated information. This article first appeared in 1996.