I. Parvovirus B19 causes a number of clinical syndromes

  1.  Fifth disease (erythema infectiosum)--Fever and constitutional sx followed about 2wks later by a red facial "slapped-cheek" rash, which may wax and wane before resolving
  2. Inflammatory arthritis (mostly in adults; symmmetric involvement of hands and, occasionally, wrists, knees, and ankles; may be associated with elevated rheumatoid factor; resolves over several weeks), often with reticular rash on trunk
  3. Aplastic anemia in sickle-cell patients and/or immunocompromised pts (e.g. HIV)
  4. Fetal infection-Can be associated with hydrops fetalis and/or congenital anemia

II. Transmitted mostly through respiratory secretions

III. Infected person is contagious 5-10d after exposure, i.e. usually before getting sick

IV. Epidemiology in pregnancy

  • 35% of preg. women are seropositive; acute infection occurs in 1-4% of pregnancies
  • Maternal-fetal transmission occurs in about 20% of cases but rarely causes fetal or neonatal disease; can be associated with fetal hydrops & death, prob. in about 10% of congenital infections (though perhaps less: J. Inf. Dis 171:1360, 1995)
  • Don't need to keep pregnant women out of situations where they could be exposed, e.g. day-care