| laboratory-acquired vaccinia virus infection--virginia, 2008. | vaccinia virus (vacv) is the live viral component of smallpox vaccine. inadvertent exposure to vacv can result in infection, and severe complications can occur in persons with underlying risk factors (e.g., pregnancy, immunodeficiencies, or dermatologic conditions). the advisory committee on immunization practices (acip) recommends smallpox vaccination for laboratory workers who handle nonhighly attenuated vacv strains or other orthopoxviruses (e.g., monkeypox, cowpox, or variola). on july 8, 20 ... | 2009 | 19644439 |