Low in school setting . Higher risk among young children in nurseries, but asymptomatic infection common in this age group.
Asymptomatic infection is probably common.
Exclusion not warranted because infection is usually mild, there are unidentified asymptomatic sources, and virus is excreted for a prolonged time. The incubation period of infectious mononucleosis. Prospective studies of a group of Yale University freshmen. Prolonged oropharyngeal excretion of Epstein-Barr virus after infectious mononucleosis.