http://www.cdc.gov/hiv/pubs/faq/faq27.htm
Centers for Disease Control and Prevention, U.S. Department of Health and Human Services
A risk of HIV transmission does exist if instruments contaminated with blood are either not sterilized or disinfected or are used inappropriately between clients. CDC recommends that single-use instruments intended to penetrate the skin be used once, then disposed of. Reusable instruments or devices that penetrate the skin and/or contact a client's blood should be thoroughly cleaned and sterilized between clients.