Health Topic

Fifth Disease

Fifth disease (erythema infectiosum) is a mild infection caused by parvovirus B19. It mostly affects children. Read about symptoms and what can help.

Reviewed Reviewed by a registered pharmacistGeneral information

Also called: Erythema infectiosum · Parvovirus B19 infection

Important: This page is general information, not medical advice. It does not recommend or prescribe any treatment. Always consult your doctor or pharmacist before starting, stopping or changing any medicine.

About Fifth Disease

Fifth disease, also called erythema infectiosum, is a viral infection caused by parvovirus B19. This virus only infects people; it's not the same type of parvovirus that dogs and cats can get.

Fifth disease mostly affects children. It often causes a bright red rash on their cheeks (sometimes called a "slapped cheek" rash).

In the United States, parvovirus B19 infections are more common in late winter, spring, and early summer. There are usually minor outbreaks of fifth disease about every 3 to 4 years.

Parvovirus B19, which causes fifth disease, can spread from person to person:

  • Through respiratory droplets, such as saliva (spit), sputum, or nasal mucus. The droplets can spread when: Someone who has the virus coughs and sneezes
  • You touch an item that has the virus on it

You are most contagious early in your infection, when you usually only have a fever or cold-like symptoms. You are not likely to be contagious after you get later symptoms such as a rash and joint pain.

About 2 out of 10 people who get a B19 parvovirus infection will have no symptoms.

But most people will get the symptoms of fifth disease, which are usually mild and can include:

  • Fever
  • Headache
  • Cough
  • Sore throat
  • Rashes
  • Joint pain

The "slapped cheek" rash is more common in children. They usually get the rash a few days after they first have other symptoms. The rash can then spread to the arms, legs, chest, back, and buttocks.

Adults who get fifth disease might also have joint pain and swelling (called polyarthropathy syndrome).

Sometimes the infection can cause serious health complications affecting the nerves, joints, or blood system. This is more likely to happen if you are pregnant, have a blood disorder such as anemia, or a weakened immune system.

Because of these risks to you and some possible risks to your baby, contact your health care provider if you are pregnant and:

  • You show signs of fifth disease (or a "slapped cheek" rash)
  • You may have been exposed to someone who has the infection

There is no routine lab test to diagnose fifth disease. Providers can often diagnose fifth disease just by seeing the "slapped cheek" rash and rashes on the body.

There is testing to show whether or not you have protection (immunity) against the B19 parvovirus or if you have had a recent infection. This test is usually not needed, but your provider may order the test if you are pregnant or at higher risk for complications of the disease.

There is no specific treatment for fifth disease. It is usually mild and goes away on its own.

To feel better, get plenty of rest. Taking acetaminophen can help with the fever and pain. Do not give aspirin to children, because it may cause Reye syndrome. This is a rare, serious illness that can affect the brain and liver.

There is no vaccine to prevent fifth disease. But you can help protect yourself and others by:

  • Washing your hands often with soap and water
  • Covering your mouth and nose when you cough or sneeze
  • Avoiding touching your eyes, nose, and mouth with unwashed hands
  • Avoiding close contact with people who are sick
  • Staying home when you are sick

Most people become immune to the virus after having it once.

Centers for Disease Control and Prevention

It sits within Children and Teenagers, Infections and Skin, Hair and Nails.

The lead U.S. institute for this subject is the National Institute of Allergy and Infectious Diseases.

When to speak to someone. Reading about a topic cannot tell you whether it applies to you. Speak to a doctor or pharmacist if symptoms are severe, sudden, getting worse, or simply not going away — and seek emergency care immediately for chest pain, breathing difficulty, sudden weakness or confusion, or a serious allergic reaction.

Research on Fifth Disease

44 studies areregistered for this condition on ClinicalTrials.gov, the U.S. National Library of Medicine's public registry. A selection is below — the links go straight to the registry entry, not to a summary of ours.

What a registered study does and does not mean. Registration means a study exists and has been declared publicly. It says nothing about whether the treatment being tested works, is safe, or is available to you. Many studies find no benefit — that is what research is for. Never seek out an experimental treatment on the strength of a registry entry alone.

Research currently under way

Research already completed

Study data from ClinicalTrials.gov, a service of the U.S. National Library of Medicine. Retrieved 2026-07-30. Registry entries are supplied by study sponsors and investigators; ClinicalTrials.gov does not verify their scientific validity. PocketsInfo is not affiliated with, and not endorsed by, the NLM or the NIH.

Where to read more

Rather than paraphrase, we point you to the primary sources. Every link below is to a government health agency, a national institute or a recognised medical body — grouped by what you are trying to find out.

Learn More

Clinical Trials

Medical subject headings

Clinicians and researchers index this subject under Erythema Infectiosum. These are the terms to use when searching medical literature.

This page is built from the MedlinePlus health topic record for Fifth Disease, a service of the U.S. National Library of Medicine (NLM), National Institutes of Health. Information is from MedlinePlus.gov. PocketsInfo is not affiliated with, and is not endorsed by, the NLM or the NIH. Retrieved 30 July 2026.