Which of the following viruses causes an acute febrile rash and produces disease in immunocompetent children but has been associated with transient aplastic crises in persons with sickle cell disease?: (A) Rubeola, (B) Varicella-zoster, (C) Parvovirus, (D) Rubella
Answer is C. Parvovirus B 19 is the causative agent of erythema infectiosum (fifth disease). It is associated with transient aplastic crisis in persons with hereditary hemolytic anemia. In adults, it is also associated with polyahralgia.