Evidently they once were protected by maternal Ab, but mothers who got vaccine rather than the illness don't have Ab that lasts as long. But the vaccine itself can't be given until around 12 months or it isn't effective. Problem of complacency - parents not getting children immunized 3. Fig 21.10 a. URT entry and initial replication.
Transient viremia carries virus to the skin and other sites.
Release of virus causes fever and malaise. Rash - rose colored at first, then lesions fill with fluid. Occur in cyclic crops as virus undergoes replication cycle. Usually not serious, but there can be fatal complications, e.g. varicella pneumonia. In children, danger of Reye's syndrome, especially if aspirin is used to reduce fever.