Walsh & Hoyt: Parvoviridae

Parvoviruses are small, nonenveloped DNA viruses with icosahedral symmetry. Parvoviruses infect a wide range of animal species, including humans; however, only one human parvovirus, designated B19, is thought to cause human disease. The virus appears to infect persons at an early age, probably by direct contact. The factors most closely associated with seroconversion are employment at certain elementary schools, contact with children 511 years old at home or 518 years old at work, and age less than 30 years. Persons in daily contact with school-age children have a fivefold increased annual occupational risk for B19 infection. Health care workers are also at increased risk. Transmission may occur via respiratory secretions, parenterally from contaminated blood products, via nosocomial and laboratory transmission, and by vertical transmission from mother to fetus.