Fifth Disease: Symptoms, Causes, Treatment, Prevention

Fifth disease is a mild viral illness that often affects school-age children^1,2. It is also called erythema infectiosum and results from human parvovirus B19 infection^1,4.

The illness often starts with mild fever or cold-like signs^3,4. A bright red “slapped cheek rash” may then appear, followed by a lacy body rash.

Most healthy children and adults recover without medical treatment^3,7. However, the infection can cause serious problems in certain high-risk groups.

Pregnant people, those with chronic blood disorders, and people with weak immunity need special care^3,4. Understanding the illness can help you know when to contact a healthcare professional.

This overview explains the symptoms and causes of fifth disease and discusses its treatment and prevention.

Fifth disease is one of the classic viral rash illnesses of childhood¹. Its everyday name comes from an older list of common childhood rash illnesses.

Parvovirus B19 infects humans and does not infect dogs or cats^2,4. Pet parvoviruses are different viruses and do not cause fifth disease in people^4,6.

Some infected people never develop symptoms^3,4. When symptoms appear, the infection characteristically progresses through three distinct cutaneous phases^1,2.

The first phase may cause fever, tiredness, headache, or other flu-like signs^1,2. The virus spreads most easily during this early phase^2,4.

The rash and joint symptoms develop later^1,2. A healthy person is generally no longer contagious once these signs appear^1,2.

Most cases improve with rest, fluids, and symptom relief^3,4. No medicine shortens uncomplicated fifth disease or directly targets the virus^1,7.

Human parvovirus B19 causes fifth disease^1,2. The virus can briefly slow the body’s production of red blood cells.

This effect causes few problems in most healthy people. It can become dangerous when red blood cells already break down faster than normal.

The virus mainly spreads through fluids from the mouth and nose. These fluids can travel when an infected person coughs or sneezes⁴.

Close contact can expose people to saliva, sputum, or nasal mucus⁴. Contaminated tissues, cups, and eating utensils may also help spread these fluids⁶.

Less common routes of transmission include the following:

People are most contagious before the classic rash develops^4,5. During this period, signs may resemble a mild cold or influenza^1,7.

People may not know they can spread the virus during this early phase⁶. The rash often appears after the amount of virus in the blood has fallen^1,2.

A person with normal immunity is generally not contagious after the rash appears^1,2. The same applies when joint pain begins⁴.

People with weak immunity may carry and spread the virus for longer periods. Their immune systems may not produce the usual response that controls infection^1,2.

Fifth disease most often affects children between ages 5 and 15^1,2. It often spreads where children gather, including schools.

Cases occur more often during late winter, spring, and early summer^2,4. Adults can also become infected, though childhood cases are more common^1,5.

Symptoms can appear 4 to 14 days after exposure. Some people have no symptoms, while others develop a mild early illness.

Possible early signs include:

Early symptoms often pass before the rash becomes visible^5,6. A child may feel better by the time the facial rash appears¹.

The classic facial rash is bright red and covers both cheeks^1,2. The skin around the mouth may remain pale.

This pattern creates the well-known slapped-cheek appearance^1,3. The rash is more common in children than adults.

A second rash may appear several days after the facial rash¹. It can spread across the following areas:

The body rash can become lacy as it begins to fade^1,3. It is typically nonitchy^1,3.

The rash often clears within 7 to 10 days. However, it can fade and return for several weeks^3,6.

Several triggers can make the rash return temporarily:

A returning rash does not mean the person has become contagious again^1,2. In healthy people, contagiousness usually ends before the rash starts.

Fifth disease in adults may not cause the classic facial rash^1,3. Joint pain and swelling are more common in adults than children^1,3.

Joint problems often affect both sides of the body^1,3. Common locations include:

Joint symptoms often improve after several weeks^1,6. However, they may continue for months in some adults^3,6.

These symptoms usually do not cause lasting joint damage⁶. Adults may develop joint pain without a noticeable rash.

A clinician can often diagnose fifth disease from the typical rash^1,4. The slapped-cheek pattern and lacy body rash are often enough for diagnosis^4,5.

Routine blood testing is not usually needed for a mild case^1,4. Testing becomes more useful when serious complications are possible^1,3.

Blood tests can look for two types of antibodies or use PCR to detect viral DNA:

Clinicians may consider testing during pregnancy or in people with weak immunity^1,4. Testing may also help people at risk for serious blood problems^1,3.

A pregnant person can pass parvovirus B19 to the developing fetus. This transmission is uncommon, but it can cause serious complications.

The virus may stop the fetus from making enough red blood cells^1,2. Severe fetal anemia can strain the heart and other organs.

In rare cases, fluid can collect throughout the fetus’s body^1,2. This condition is called hydrops fetalis.

Infection during pregnancy can also increase the risk of pregnancy loss. However, fetal complications do not occur after every pregnancy exposure^3,6.

A clinician may arrange blood tests and added pregnancy monitoring after infection^3,7. Monitoring can include more visits, bloodwork, or ultrasound scans⁷.

Parvovirus B19 targets cells that later become red blood cells. It can briefly stop red blood cell production.

This pause may trigger a transient aplastic crisis in certain blood disorders^1,2. This crisis is a sudden, severe fall in red blood cell production.

Higher-risk disorders include:

Hemolytic anemia means red blood cells break down faster than the body replaces them. A temporary stop in production can then cause a sharp drop in blood cells.

People with weak immunity may not clear the virus normally^1,2. Persistent infection can cause ongoing or chronic anemia^1,2.

Risk can be higher with cancer, organ transplantation, HIV, or immune-suppressing treatment. These patients may not develop the usual rash or joint symptoms¹.

Uncomplicated fifth disease usually goes away without specific antiviral treatment^1,4. Antibiotics do not treat the virus.

Home care focuses on comfort while the body clears the infection^1,3. Helpful steps include:

Acetaminophen can help reduce fever and pain^4,6. Ibuprofen may help some older children and adults with pain or joint swelling^5,7.

Do not give ibuprofen to a baby under 6 months without clinician advice. Medicine choices may depend on age, health history, and other treatments.

Never give aspirin to a child or teenager with fifth disease^4,5. Aspirin during a viral illness can raise the risk of Reye syndrome^4,5.

Reye syndrome is a rare condition that can harm the brain and liver^4,5. Ask a clinician or pharmacist if you are unsure which medicine is suitable.

Severe anemia may require hospital-based supportive care and blood products. Some patients may need a blood transfusion under specialist care^2,7.

A fetus with severe anemia may require treatment from a maternal-fetal medicine team. Intrauterine transfusion may be used for severe fetal anemia.

Persistent infection in a person with weak immunity may cause persistent anemia^1,2. Intravenous immunoglobulin may be recommended for some immune-deficient patients⁶.

Intravenous immunoglobulin contains donated antibodies and is given through a vein. It is not routine treatment for an otherwise healthy person with fifth disease⁶.

Contact a healthcare professional if signs of fifth disease develop during pregnancy^3,4. Make contact even if no rash has appeared, since contagiousness starts earlier¹.

Also contact a clinician if signs appear during pregnancy^3,4. Blood testing can show recent infection or past immunity^3,4.

Medical advice is important in these situations:

Marked paleness, rapid breathing, or a rapid pulse can occur with severe anemia⁶. People at high risk (such as those with sickle cell disease, thalassemia, hereditary spherocytosis, other chronic hemolytic anemias, or a weakened immune system) should seek emergency or same-day urgent medical care right away if these signs develop, because parvovirus B19 can cause a life-threatening aplastic crisis.

A rash alone is often mild in an otherwise healthy person^3,4. However, a clinician can check whether another condition may be causing the symptoms.

No approved vaccine currently prevents fifth disease^4,6. Prevention focuses on limiting contact with infected respiratory fluids^4,6.

These everyday habits can reduce exposure:

Prevention is difficult because people spread the virus before the rash appears^4,6. At that stage, the illness may seem like a minor cold⁴.

Stay home while feverish or feeling unwell⁴. Follow guidance from your healthcare provider, school, childcare center, or workplace.

Healthy children can often return to school once the rash appears⁷. At that stage, they are generally no longer contagious^1,2.

A lingering or returning rash does not restart the contagious period^1,2. Joint pain also tends to begin after contagiousness has ended^1,2.

Different guidance may apply to people with weak immunity. They can remain infectious when their bodies do not produce an effective antibody response.

Most healthy people recover completely from fifth disease^3,6. The main illness often improves within one to three weeks⁷.

The rash may last longer or return after certain triggers^3,6. Adult joint pain may also continue for weeks or months^3,6.

These joint symptoms usually end without lasting problems^3,6. Most people develop lasting immunity after one parvovirus B19 infection¹.

Fifth disease is usually a mild illness caused by human parvovirus B19^1,4. Rest, fluids, and suitable symptom relief are often enough for healthy people^3,7.

The infection can become serious during pregnancy or with certain blood disorders. People with weak immunity may also develop persistent infection and chronic anemia^1,2.

Recognizing the early contagious phase can help limit spread^4,6. Timely medical advice can also protect people with a higher risk of complications¹.