Everything You Need to Know About Fifth Disease

Fifth disease occurs following exposure to parvovirus B19. The disease is sometimes called slapped-cheek disease because it presents with a bright red facial rash. 

Fifth disease is more common in children. It can sometimes affect adults and is especially severe in pregnant people or people who are immunocompromised (having a weak immune system) or who have anemia (a low number of healthy red blood cells). Fifth disease can sometimes go away on its own, but treatment can manage symptoms and relieve itch. 

The article will cover everything you need to know about fifth disease, including its appearance, symptoms, causes, diagnosis, treatment, and more. 

What Does Fifth Disease Look Like?

Fifth disease generally starts with symptoms similar to flu or the common cold. The rash will appear once these symptoms pass (within a few days).

The bright red rash will appear on the face—mainly the cheeks, which is why it is sometimes called slapped-cheek disease. The rash can sometimes extend over the nose and around the mouth. It generally lasts a few days to two weeks and can be itchy. It fades from the center outward, resulting in a blotchy appearance.

A second rash, blotchy or lacy in appearance, can develop on the trunk and extend to the arms and legs. This rash should resolve in about a week. But after the rash has cleared, it can reappear if the skin is irritated.

Most adults with fifth disease experience a mild rash, but a rash doesn't always occur. And some adults will be asymptomatic (have no symptoms). Adults and adolescents may have swollen and painful knuckles, wrists, or knee joints. This usually resolves in one to two weeks but can last for months.

Fifth Disease Symptoms

Once a child or adult acquires a parvovirus B19 infection, they will experience mild flu-like symptoms. During this period, the virus is the most contagious.

Symptoms of fifth disease in this early, contagious stage might include:

• Fatigue
• Aches and pains 
• Low-grade fever
• Headaches 
• Runny nose 
• Sore throat
• Nausea or vomiting
• Diarrhea
  

Symptoms will show up four to 14 days after exposure to parvovirus B19. Around 4 out of 5 children with the infection will have mild symptoms for about a week before the rash appears. About 1 in 5 children will have no symptoms before the rash appears.

The rash will first appear on the face as a raised, bright red patch. It shows up four to 21 days after exposure. The rash will be itchy, and the flu-like symptoms will have dissipated. Some children with fifth disease will also experience joint pain and swelling.

For most children with healthy immune systems, fifth disease is a mild illness that rarely leads to long-term problems. It can be dangerous for immunocompromised children because it can trigger severe anemia.

According to the American Academy of Pediatricians, the virus can cause red blood cell counts to drop so low that a blood transfusion might be necessary. Fifth disease is especially dangerous for people with sickle cell anemia, a genetically inherited disorder of the hemoglobin in red blood cells.

What Causes Fifth Disease?

The parvovirus B19 infection causes fifth disease. It is an airborne virus that can spread easily through respiratory secretions (salvia, sputum, and nasal mucus), which makes it common among elementary school students. It can also be spread through blood or blood products.

A pregnant person can pass the virus to their fetus. Any pregnant person exposed to the virus should immediately inform their healthcare provider.

According to the Centers for Disease Control and Prevention (CDC), most cases of parvovirus B19 in the United States occur in the late winter, spring, and early summer. Mini outbreaks of the virus will occur every three to four years. But the disease can spread anytime and affect anyone of any age.

How Is Fifth Disease Diagnosed?

A healthcare provider can diagnose fifth disease based on the symptoms. The slapped-cheek rash is a strong indication of the disease.

A blood test can also be done to look for antibodies (immune proteins) to the virus. This blood test is not routine and only done in exceptional circumstances, such as for pregnant people or immunocompromised people exposed to the virus.

How Is Fifth Disease Treated?

For healthy people who develop fifth disease, no treatment is needed. The condition is self-limiting and will improve with rest and fluid intake.

For joint, head, or throat pain, you can give your child over-the-counter (OTC) Tylenol (acetaminophen) as needed to relieve their symptoms. You can also use an antihistamine medicine like Benadryl (diphenhydramine) to manage itch.

In rare cases, intravenous immunoglobulin (IVIG) treatment can be given. This treatment is usually reserved for severe and life-threatening cases (i.e., for immunocompromised people or people with sickle cell disease). It contains antibodies that work against parvovirus B19.

Can Adults Get Fifth Disease?

Most adults have antibodies that prevent them from developing fifth disease. This is often because they were exposed during childhood.

Joint pain and other symptoms in adults usually resolve without any long-term problems. Joint pain and swelling can be managed with anti-inflammatory drugs, while itch can be treated with an antihistamine. 

Parvovirus B19 may cause severe disease in immunocompromised adults. The virus can lead to acute, severe, or chronic anemia for this group. Once the infection has resolved, the acute anemia will also resolve. Chronic anemia will need medical treatment, potentially long-term.

Fifth Disease During Pregnancy

At least half of pregnant people are immune to the parvovirus B19. They will not develop the virus even if exposed.

The disease is generally mild for most pregnant people. Symptoms may include joint pain and swelling, and a mild rash. The fetus is unlikely to be affected, but it is still possible for them to acquire the infection.

While rare, a pregnant person who has contracted parvovirus B19 can develop severe anemia, sometimes leading to a miscarriage (loss of pregnancy before the 20th week). The CDC says this is uncommon, affecting less than 5% of pregnant people with fifth disease, and generally occurs in the first half of pregnancy.

It is unlikely that the fetus or baby will develop anemia caused by the infection, but it is possible. There is no treatment for fifth disease in pregnancy, but your healthcare provider will want to monitor your pregnancy. Such monitoring includes blood work, ultrasounds, and additional prenatal visits.

When Is Fifth Disease Contagious?

The time between exposure to parvovirus B19 and the start of the illness is the most contagious period, which is four to 12 days. Once the rash has appeared, the condition is no longer contagious. 

Outlook After Fifth Disease

The fifth disease rash should resolve within a few days to a couple of weeks after it starts. If your child develops a second rash, that rash should go away within a few days. There are instances in which the rash can come and go several times.

When your child experiences flu-like symptoms, they are contagious and should stay home from school or daycare. However, once the rash appears, they are no longer contagious and can return if they feel better.

Immunocompromised people should immediately see their healthcare provider if they are exposed to the virus. A healthcare provider may prescribe additional treatments to prevent disease complications. 

A pregnant person exposed to fifth disease should immediately inform their healthcare provider. While there is no approved treatment for the disease in pregnancy, the healthcare provider will monitor you for potential complications, including anemia. 

Can Fifth Disease Be Prevented?

There is no vaccine available to prevent fifth disease. Because the disease is spread through respiratory secretions, good hygiene can help prevent the infection.

You can reduce the risk of infection by:

• Washing your hands well and often
• Eating a healthy diet
• Not sharing personal items
• Avoiding contact with infected persons
  

Similar Rashes to Fifth Disease

Fifth disease was given this name due to its ranking in the standard list of rash-causing childhood diseases. Other conditions in this ranking are measles (first), scarlet fever (second), rubella (third), Dukes' disease (fourth), and roseola (sixth).

Roseola (sixth disease) can sometimes be mistaken for fifth disease. It causes a high fever that can last a few days. Once the fever passes, a rash will appear across the trunk, extremities, and face. Roseola also causes symptoms that help set it apart from fifth disease, including eyelid swelling.

Scarlet fever, like fifth disease, causes a red rash. It results from the same bacteria that causes strep throat. Around 10% of children will react more severely to the bacteria and develop scarlet fever. Initial symptoms of scarlet fever include a sudden fever, sore throat, vomiting, and a white strawberry tongue (red and bumpy). 

The scarlet fever rash will start on the face after a day or two of the initial symptoms. Scarlet fever is treated with antibiotics, which can prevent rheumatic fever and other complications. 

When to See a Healthcare Provider

Contact your child's healthcare provider if you think they have fifth disease or have been exposed to parvovirus B19. This is especially important if the child has an itchy rash or severe joint pain. 

You should also contact a healthcare provider if you are pregnant or have a weakened immune system and are exposed to fifth disease. They can request a blood test and monitor your symptoms if your test comes back positive. 

If your child is immunocompromised from a cancer like leukemia or has certain types of anemia, such as sickle cell disease, they should go to the hospital if they are exposed to parvovirus B19 and start to experience disease symptoms.

You should also reach out to your child's healthcare provider if they are diagnosed with fifth disease (regardless of immune status) and not getting better or experiencing joint swelling or showing signs of anemia, such as severe fatigue and pale skin.

Summary 

Fifth disease occurs after exposure to parvovirus B19 and causes a bright red facial rash. It typically starts with flu-like symptoms, which last a few days before the rash appears. This is also the most contagious time. 

Fifth disease affects more children than adults. It can be especially severe in pregnant people or those with compromised immune systems because it can lead to life-threatening anemia. The condition can sometimes go away on its own, but treatment might be needed to manage symptoms and relieve itch.

Contact a healthcare provider if you or your child has been exposed to parvovirus B19 and experiencing severe symptoms or have underlying health conditions. Treatment and monitoring are important for people with weak immune systems and anyone who is pregnant.