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Erythema Infectiosum (Parvovirus B19 Infection)

(Fifth Disease; Slapped-Cheek Disease)


Brenda L. Tesini

, MD, University of Rochester School of Medicine and Dentistry

Reviewed/Revised May 2023
Topic Resources

Erythema infectiosum is caused by acute infection with human parvovirus B19. In children, it causes mild constitutional symptoms and a blotchy or maculopapular rash beginning on the cheeks and spreading primarily to exposed extremities. In a fetus, it may be fatal. Diagnosis is clinical, and treatment is generally not needed.

Erythema infectiosum, often referred to as fifth disease, is caused by human parvovirus B19. The name "fifth disease" is used because it is considered the fifth viral infection that commonly causes rash in children (the first four are measles, rubella, chicken pox, and roseola). It is also sometimes called slapped-cheek disease.

It occurs mostly during the spring, commonly causing localized outbreaks every few years among children (particularly children aged 5 to 7 years).

Spread seems to be by respiratory droplets and by percutaneous exposure to blood or blood products, with high rates of secondary infection among household contacts; infection can be asymptomatic.

Infection may also occur in adults and may cause various clinical syndromes, including papular-purpuric gloves-and-socks syndrome, arthropathy, transient aplastic crisis, and pregnancy loss or hydrops fetalis Hemolytic Disease of the Fetus and Neonate Hemolytic disease of the fetus and neonate is hemolytic anemia in the fetus (or neonate, as erythroblastosis neonatorum) caused by transplacental transmission of maternal antibodies to fetal... read more . Based on seroprevalence surveys, 50 to 80% of adults have evidence of prior parvovirus B19 infection, which likely confers protective immunity for immunocompetent people.

Pathophysiology of Erythema Infectiosum


Parvovirus B19 infection in pregnancy

Pathophysiology reference

  • 1. Enders M, Weidner A, Zoellner I, et al: Fetal morbidity and mortality after acute human parvovirus B19 infection in pregnancy: Prospective evaluation of 1018 cases. Prenat Diagn 24(7):513–518, 2004. doi: 10.1002/pd.940

Symptoms and Signs of Erythema Infectiosum

The incubation period of parvovirus B19 infection is 4 to 14 days. Typical initial manifestations of erythema infectiosum are nonspecific flu-like symptoms (eg, low-grade fever, slight malaise).

Several days later, an indurated, confluent erythema appears over the cheeks (“slapped-cheek” appearance), and a symmetric rash appears prominently on the arms, legs (often extensor surfaces), and trunk, usually sparing the palms and soles. The rash is maculopapular, tending toward confluence; it forms reticular or lacy patterns of slightly raised, blotchy areas with central clearing, usually most prominent on exposed areas.

The rash and the entire illness typically last 5 to 10 days. However, the rash may recur for several weeks, exacerbated by sunlight, exercise, heat, fever, or emotional stress.

Manifestations of Erythema Infectiosum

Other manifestations of parvovirus B19 infection

A few patients (more commonly children) develop papular-purpuric gloves-and-socks syndrome (PPGSS), which causes papular, purpuric, or petechial lesions limited to the hands and feet and is often accompanied by fever and oral and/or genital lesions.

Some adults with parvovirus B19 infection develop mild joint pain and swelling (nonerosive arthritis) that may persist or recur for weeks to months.

Diagnosis of Erythema Infectiosum

  • Physical examination with characteristic rash

  • For children with risk factors for complications, viral testing and complete blood count

  • For pregnant patients, antibody measurement and ultrasonography

The rash's appearance and pattern of spread are the only diagnostic features; however, some enteroviruses may cause similar rashes. Distinguishing between these viral etiologies is seldom needed for the clinical care of otherwise healthy children. Rubella Diagnosis (See also Congenital Rubella.) Rubella is a viral infection that may cause adenopathy, rash, and sometimes constitutional symptoms, which are usually mild and brief. Infection during early pregnancy... read more Diagnosis can be ruled out by serologic testing; an exposure history is also helpful. Other childhood exanthems have distinct diagnostic features.

Serologic testing is not required in otherwise healthy children; however, children with a known hemoglobinopathy or immunocompromised state should have viral and/or antibody testing as well as a complete blood count (CBC) and reticulocyte count to detect hematopoietic suppression.

In children with transient aplastic crisis or adults with arthropathy, the presence of IgM-specific antibody to parvovirus B19 in the late acute or early convalescent phase strongly supports the diagnosis.

Parvovirus B19 viremia also can be detected by quantitative polymerase chain reaction (PCR) techniques, which are generally used for patients with transient or chronic aplasia, patients who are immunocompromised, and fetuses or neonates with hydrops fetalis or congenital infection.

In pregnant patients, antibodies are measured; IgG suggests immunity due to prior infection (which is usually reassuring) and IgM indicates current or recent infection (which raises concern for potential fetal morbidity). Initial assessment of fetal status is with ultrasonography.

Treatment of Erythema Infectiosum

  • Supportive care

Only symptomatic treatment of erythema infectiosum is needed.

Key Points

  • Children develop low-grade fever and slight malaise followed several days later by an indurated, confluent erythema on the cheeks (“slapped-cheek” appearance) and a symmetric rash that is most prominent on the arms, legs, and trunk.

  • There is mild, transient suppression of erythropoiesis that is asymptomatic except sometimes in children with hemoglobinopathies (eg, sickle cell disease) or other red blood cell disorders (eg, hereditary spherocytosis), or immunosuppression.

  • Risk of fetal death is 2 to 6% after maternal infection, with risk greatest during the first half of pregnancy.

  • Testing is done mainly in children with transient aplastic crisis or adults with arthropathy.

  • Treatment is symptomatic, but patients who are immunocompromised may benefit from IV immune globulin.

NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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