Abstract: Employee #1 was a program technician's aide who worked with clients with different levels of mental retardation. She taught life/community skills mobility and assisted with personal care needs when necessary. Employee #1 developed hepatitis B; this diagnosis was confirmed at the local hospital. Mentally retarded clients are known to have a higher prevalence of hepatitis B than the general population. Clients often exhibit aggressive and assaulting behavior toward other clients and aides. CDC considers the risk to be on a par with hospital workers. Training for prevention of transmission of HBV and HIV was lacking, although gloves were available. Employee #1 cannot specify the incident that caused her to contract the disease.