A nurse (index case) at a rehabilitation hospital was diagnosed with acute parvovirus B19 infection. A 2-year-old male patient was identified as the source patient. The epidemiological investigation focused on 15 individuals with symptomatic disease or risk factors for complications of parvovirus B19 infection. Serologic testing confirmed parvovirus B19 infection in the index case and source patient and identified a second health care worker who possibly contracted acute parvovirus B19 infection through nosocomial transmission. Parvovirus B19 infection can cause serious complications in pregnant women, persons with chronic hemolytic anemia, and persons with immunodeficiencies. Measures to control the transmission of parvovirus B19 infection should be part of the infection control plan at rehabilitation hospitals.