A nurse is reinforcing teaching about infection control with the guardian of a school-age child who has varicella. The nurse should inform the guardian that which of the following findings is an indication that the child is no longer contagious?

A. Itching has subsided: While reduced pruritus indicates healing and comfort improvement, it does not correlate with viral shedding or contagiousness. Children with varicella can still transmit the virus until all lesions are fully crusted, regardless of the presence or absence of itching. B. All vesicles have crusted over: Varicella (chickenpox) is contagious from 1–2 days before the rash appears until all lesions have formed crusts. Crusting of vesicles indicates that viral shedding has ended, and the child is no longer infectious. This is the primary clinical indicator used to determine when isolation precautions can safely be discontinued. C. Temperature is less than 37.8° C (100° F): Fever reduction signals improvement in systemic infection and overall health but does not reflect cessation of viral shedding. Children may remain contagious despite a normal temperature until the lesions crust over. D. The antibiotics regimen is complete: Antibiotics are not effective against varicella, a viral infection, and completing an antibiotic course does not influence contagiousness. Transmission risk is determined by lesion status, not antibiotic therapy.