Three children who presented with localized vesicular rash in the diaper area were found to have primary varicella-zoster infections. Primary varicella can closely mimic genital herpes simplex virus (HSV 1 or 2), which may be an indicator of sexual abuse. To avoid unfounded investigation for sexual abuse, primary varicella-zoster infection must be included in the differential diagnosis. Direct fluorescent antibody testing is a sensitive and specific diagnostic test that can be used to distinguish HSV 1 or 2 from varicella-zoster.