Fifth Disease Cause

The fifth disease cause is parvovirus B19. Parvovirus B19 is a virus that commonly infects humans. Although animals may be vaccinated to prevent other parvoviruses, the cause of fifth disease (parvovirus B19) cannot infect animals.

 

Fifth Disease Cause: A Summary

Fifth disease is caused by infection with human parvovirus B19.
 

Understanding Parvovirus B19

Parvovirus B19 is a virus that commonly infects humans. About 50 percent of all adults have been infected sometime during childhood or adolescence. Parvovirus B19 infects only humans. There are other parvoviruses that infect animals. Parvovirus B19 is a small, single-stranded DNA virus.
 
Parvovirus can cause a variety of illnesses in humans including:
 
  • Fifth disease (erythema infectiosum or slapped cheek syndrome)
  • Arthropathy (disease of a joint)
  • Transient aplastic crisis (a condition where the body cannot make red blood cells)
  • Chronic anemia (low red blood cells)
  • Fetal infection.
     
Many of these conditions occur because parvovirus B19 causes problems with bone marrow cells.
 

Other Parvoviruses

Parvovirus B19 infects only humans. Pet dogs or cats may be immunized against "parvovirus," but these are animal parvoviruses that do not infect humans. Therefore, a child cannot "catch" parvovirus from a pet dog or cat, and a pet cat or dog cannot catch human parvovirus B19 from an ill child.
 
Written by/reviewed by: Arthur Schoenstadt, MD
Last reviewed by: Arthur Schoenstadt, MD