A 16-year-old varicella-seronegative resident at a chronic care facility received varicella vaccine; 15 days later he developed severe varicella. Subsequently, a 13-year-old resident and a 39-year-old health care worker developed mild varicella. We demonstrate that vaccine-strain virus was transmitted to both persons, and that transmission included at least 2 variant vaccine strains. A 16-year-old varicella-seronegative resident at a chronic care facility received varicella vaccine; 15-day-old resident and a 39-year-old health care worker developed mild varicella. We demonstrate that vaccine-strain virus was transmitted to both persons, and that transmission included at least 2 variant vaccine.