Among healthcare workers: - 14 occupational HIV seroconversions (including 4 cases of antiretroviral prophylaxis failure) and 34 suspected infections between 1983 and 2005; - 55 occupational HCV seroconversions between 1991 and 2005; - no reported HBV seroconversions since 2005. Risk of viral transmission: - high in the event of a needle stick following an intravenous or intra-arterial procedure; - should not be overlooked in the event of a puncture with suture or subcutaneous needles (particularly with regard to HCV); - lower, but documented following blood-to-skin or blood-to-mucous membrane contact. Importance of applying standard precautions and providing appropriate care in the event of an accident involving exposure to blood.