What is Parvovirus B19?
Parvovirus B19 is a virus that commonly infects humans; about 50% of all adults have been infected sometime during their childhood or adolescence. Parvovirus B19 infects only humans. There is animal parvovirus, but they do not infect humans. Therefore, a person cannot catch ParvovirusB19 from a dog or a cat.
Humans are the only known hosts of parvovirus B19 infection. Outbreaks commonly occur among school-age children, especially in the winter and spring. Secondary spread is common, occurring in about 50% of susceptible household contacts. Transmission is felt to be through respiratory secretions.
What illnesses does Parvovirus B19 infection cause?
The most common illness caused by parvovirus B19 infection is “fifth disease,” a mild rash illness that occurs most often in children. The ill child typically has a “slapped Cheek” rash on the face and a lacy red rash on the trunk and limbs. Occasionally, the rash may itch. The child is usually not very ill, and the rash resolves in 7 – 10 days. Once a child recovers from parvovirus infection, he or she will develop lasting immunity, which means that the child is protected against future infection. An adult who has not previously been infected with parvovirus B19 can be infected and become ill. They may develop a rash, or joint pain, or swelling, or both. The joint symptoms usually resolve in a week or two, but they can last several months.
Are these illnesses serious?
Fifth disease is usually a mild illness. It resolves without medical treatment among children and adults who are otherwise healthy. Joint pain and swelling in adults usually resolve without long term disability. During outbreaks of fifth disease, about 20% of adults and children are infected without getting any symptoms at all. Continue reading


