An Overview of Fifth Disease and Parvovirus B19

Fifth disease is a common illness. It is seen most often in children, but adults can get it, too. It is a condition that can cause a rash along with cold or flu-like symptoms.

It is usually mild and not dangerous to those in good health. However, it could be a concern for children and adults with certain health conditions and for pregnant women.

Here’s what you need to know about fifth disease symptoms, treatments, complications, and prevention.  

What It Is

Fifth disease is an illness similar to the common cold, and like the common cold, it is the result of a virus. The virus that causes fifth disease is parvovirus B19.

This viral illness is called fifth disease because doctors identified it as the fifth classic childhood illness that causes a rash. The other four are measles, scarlet fever, rubella (German measles), and fourth disease (or Dukes' disease). There is a sixth rash disease, as well. It is known as roseola.

The medical name for fifth disease is erythema infectiosum. But, it is also known around the world as slapped cheek syndrome.

Pets and Parvovirus

The parvovirus that causes fifth disease in humans (parvovirus B19) is not spread through contact with pets. The parvovirus that infects dogs is the canine parvovirus (CPV) and the one that affects cats is the feline parvovirus (FPV).

When dogs and cats get their version of the parvovirus, it is serious and potentially life-threatening for them. Thankfully, there are vaccines available to prevent this dangerous virus in pets.

Symptoms

While some people don't show any signs of illness, most people who get parvovirus B19 have mild symptoms. The symptoms are often the same as a cold or the flu and can include the following: 

• Fever
• Headache
• Runny nose
• Stuffy nose
• Sore throat
• Fatigue
• Nausea
• Vomiting
• Diarrhea
• Muscle aches
• Swollen glands

There are also two other symptoms of fifth disease that set it apart from other viruses: rash and joint pain.

Rash

There is a characteristic rash that can help doctors tell the difference between fifth disease and other viral illnesses. The fifth disease rash usually starts on the face, causing bright red cheeks that look like they have been slapped. It may then move on to cover the body, arms, and legs.

The rash may be itchy and it can have a lace-like or web-like pattern as it fades. It can last for weeks, especially with exposure to heat or the sun.

The rash is more likely to be seen in children from 4 to 10 years old. It can still show up in older children and adults, but it tends to be less noticeable. 

Joint Pain

Fifth disease can also cause pain in the joints of the hands, wrists, feet, ankles, and knees. There may also be swelling, and it can feel similar to arthritis.

Joint pain may only last a week or two, or it can continue for months. The symptoms of joint pain and swelling are more common in adults than in children.

How It Spreads

Fifth disease most commonly spreads amongst children through saliva and mucus, spread by respiratory expulsions such as coughing and sneezing.

Person to Person Contact

The disease can spread when:

• Shaking hands with someone with the virus after they touch their nose or mouth 
• Touching a surface that someone with the illness just touched after touching their nose or mouth

Respiratory Droplets

The disease can spread when:

• Breathing in the virus after someone near you coughs or sneezes
• Sharing a spoon, fork, or straw with someone who has the virus 

Blood

The disease can spread:

• During pregnancy from mother to baby
• From medical procedures such as the transfusion of blood and blood products or organ and bone marrow transplants

During Pregnancy

It can be scary to get sick while you’re pregnant, especially when you know some illnesses can be dangerous to you or your baby. Fifth disease is one that can make you worry. But, thankfully, the chances of having dangerous pregnancy complications from parvovirus B19 are very low.

Other than the discomfort of a viral illness, parvovirus B19 may not cause any problems for you, your baby, or your pregnancy.

According to the Centers for Disease Control and Prevention (CDC), about 50% of pregnant women are already immune to the human parvovirus. This immunity protects them from getting fifth disease and passing it to the baby. For those who are not immune and get parvovirus during pregnancy, the illness is typically mild. It is not likely to cause any problems, and most babies are born healthy.

However, in a small percentage of women who get fifth disease while they’re pregnant, the virus can lead to serious complications that affect the baby and the pregnancy. It is rare, but fifth disease during pregnancy can: 

• Cause severe anemia in the baby
• Affect the baby’s heart
• Affect the baby’s liver
• Lead to the loss of the pregnancy

Exposure to parvovirus B19 is more dangerous during the first 20 weeks than later in pregnancy. If you believe you have been exposed to fifth disease or you have symptoms of the virus, talk to your doctor. Your doctor may want to examine you and take a blood test.

If your doctor confirms that you have or had fifth disease during your pregnancy, they will monitor you and your baby more closely.

Course of Illness

Once you come in contact with the human parvovirus, it can take anywhere from four days to two weeks to experience symptoms. This window of time is called the incubation period.

The rash doesn't show up right away. It can take up to three weeks to appear, first in the face, and then on the body. It can last for weeks. But, once you see it, the virus is no longer contagious, and it is safe to go back to school or work.

Fifth disease lasts for about 10 days, but it can continue for a few weeks depending on your health and immune system. It can linger on longer than a few weeks, but that’s rare.

Most healthy children and adults do not have any long-term problems after getting better. Plus, once you get the virus and recover, your body builds up antibodies to fight it off. If you face its return in the future, you are immune and protected from getting it again.

Diagnosis

Most children and adults who get fifth disease don't know that’s what they have. It is often passed off as a typical cold or viral infection. Many people with the illness will not even go to the doctor, especially if they don’t have the rash. 

If you do seek medical help, your doctor can diagnose fifth disease through a physical examination and blood work. When there’s a visible rash, it’s easier to diagnose. If there isn’t a rash, the doctor can order a blood test to look for antibodies in the blood. But, chances are, your doctor will not do a blood test unless it is necessary.

A blood test is necessary if you’re pregnant or if you, your child, or a family member have a health condition that could get worse from the parvovirus.

A blood test can show if:

• You have immunity to the virus from a past infection
• You are not immune to the virus 
• You do not have the virus
• You have recently had an infection

Treatment

Since fifth disease is a viral illness like the common cold, it will run its course then go away on its own. Your doctor will not prescribe an antibiotic. Antibiotics kill bacteria, not viruses. 

The doctor’s recommended treatment may include: 

• Tylenol for fever or joint discomfort
• An antihistamine such as Benadryl (diphenhydramine) for the rash
• Rest 
• Restriction of activity until feeling better

Coping

It’s not fun to be sick with a virus. But, it's a natural process, and there’s not too much you can do about it. Here are some tips to help you or your child get through it.

• Drink plenty of fluids. Keep the body hydrated by drinking water, tea, juice, or broth.
• Get extra sleep. Let the body get enough rest so it can use its energy to fight off the illness. 
• Have a little patience. The illness will go away with time. 
• Talk to the doctor about medicine. It is not safe to give children aspirin or products containing aspirin, but there are other medicines your child can take. Ask the doctor about giving your child Tylenol (acetaminophen) or a safe cough and cold medication. Adults can usually take acetaminophen or ibuprofen for joint pain and other symptoms. Of course, it's always best to check with your doctor or a pharmacist to be sure it's OK.
• Pass the time. When not resting, you can keep yourself or your child from going stir crazy by playing board or card games, doing puzzles, reading, watching a little TV, or going online. Just be sure you’re also turning the electronics off and getting some real rest, too.

Prevention

Unfortunately, there is no way to prevent catching this virus completely.

In the meantime, you and your family can take steps to help protect yourselves by: 

• Washing hands often with soap and water
• Using hand sanitizer when soap and water are not available
• Staying away from anyone who is coughing and sneezing
• Not touching the eyes, mouth, or nose without washing hands first
• Keeping the immune system healthy through eating right, drinking plenty of fluids, getting enough rest, and reducing stress

If you or your child get a virus, you can prevent spreading it to others by:

• Staying home during the illness
• Avoiding other people, especially pregnant women
• Covering the mouth when coughing
• Covering the nose when sneezing
• Washing hands often especially before touching common surfaces and objects

Complications

Complications of fifth disease during childhood are rare. Most children recover quickly and without any problems.

Adults may have a mild illness or experience joint pain and swelling for a few weeks or months. Even then, the virus usually goes away on its own without the need for treatment. Of course, while complications are not common, they can develop.

The chances of having complications from parvovirus B19 are higher if you:

• Have a compromised immune system due to HIV, cancer, or an organ transplant
• Have a low red blood cell count from a condition such as iron deficiency, thalassemia, or sickle-cell disease
• Are pregnant

The human parvovirus can cause the body to stop making red blood cells, which can lead to severe anemia or worsening anemia in those with iron deficiency anemia, thalassemia, or sickle cell. It can also be dangerous for a growing baby during pregnancy. 

In rare, severe cases, treatment includes hospitalization for blood transfusions or immune globulin therapy.

When to Call the Doctor

Fifth disease in healthy children and adults is just like a cold. You generally don't need to call the doctor for a mild illness. However, you should contact the doctor if:

• You have a newborn or a young infant with a temperature over 100.4 F (38 C) or symptoms of illness
• You have an older child with a fever over 102 F (39 C)
• The symptoms are getting worse 
• You, your child, or a household member has a weak immune system or other health condition
• You are pregnant

A Word From Verywell

It can be scary if your child isn’t feeling well and you notice a bright red rash on their face. But, it’s probably not a serious condition. Viruses can cause rashes and flu-like symptoms, and fifth disease is just one of these common childhood illnesses. Like a typical cold, parvovirus B19 is usually mild and goes away on its own.

Fifth disease is not something to worry over if you, your child, and other household family members are in good health. You can treat it the same way you would treat a cold or the flu. But, you should call the doctor if you have any questions or concerns especially if someone in your family is pregnant or has special health needs.