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What is fifth disease?
Fifth disease is a mild viral infection caused by human parvovirus B19. Fifth disease got its name because it was listed as the fifth of several illnesses that commonly caused rashes in children before the modern era of vaccines. Four others worth mentioning are measles (rubeola), chicken pox (varicella), German measles (3-day measles, rubella) and roseola. You may also hear fifth disease called "slapped cheek disease" or "face disease" because of the rash that may appear on the face. The medical name for fifth disease is erythema infectiosum (say: ear-uh-thee-muh en-fekt-shee-oh-sum).
About half of people get fifth disease sometime during childhood or their teens. Once you've had fifth disease, you will not be at risk of getting it again.
What are the symptoms of fifth disease?
The most common symptom of fifth disease is a bright red raised rash that appears first on the face, and then (a day later) on the arms, legs and trunk of the body. Children may have mild flu-like or cold-like symptoms before the rash surfaces, such as a low fever, sore throat and headache.
Adults who catch the virus usually don't develop the rash. Instead, they are more likely to experience joint pain or swelling, usually of the hands, wrists, knees and ankles. This can last several months, but usually resolves after 1 to 2 weeks. However, some adults may not experience any symptoms.
Symptoms usually show up about 4 to 14 days after exposure, although the rash may not appear for as long as 3 weeks. About 20% of people infected have no symptoms. Others may have some symptoms that don't match the typical fifth disease symptoms.
The rash of fifth disease usually goes away within 2 weeks. It fades from the center outward, making it look blotchy or "lacy." But it may return for several weeks, triggered by sunlight, heat, exercise, fever or stress.
Who is at risk for fifth disease?
Fifth disease generally affects children 5 to 7 years old. It is most common in the spring.
Adults who haven't had fifth disease before can catch it, but many adults have had it as children and are immune.
How is fifth disease spread?
Fifth disease is spread by coming into contact with saliva or mucus carrying the virus. For example, it can be spread by coughing, sneezing or sharing items. Frequent hand washing may help reduce the spread of the virus.
Unlike other rash illnesses (such as measles), once the symptoms appear, you are no longer contagious.
Fifth disease is caused by parvovirus, but it isn't the same type of "parvo" that infects dogs and cats, so you aren't at risk of catching it from pets.
How is fifth disease diagnosed?
Your doctor can usually tell if you have fifth disease by examining the pattern of the rash. A blood test also can be used to check for the antibody to parvovirus. An antibody is a type of protein that your body makes in response to infections. While the blood test is not usually needed, your doctor may want to do it if you have other conditions that might put you at greater risk for complications from fifth disease.
How is fifth disease treated?
Most cases of fifth disease are mild, so the only treatment needed is that which relieves the symptoms.
Fever and flu symptoms in children can be treated with acetaminophen (brand name: Tylenol).
Adults who have joint pain or swelling may need to rest and restrict activity. They also may want to take medicines like acetaminophen, aspirin or ibuprofen (brand names: Advil, Motrin) if recommended by their doctor. Avoid giving children and teens under 18 aspirin because it can cause a serious illness called Reye's syndrome.
What are the complications of fifth disease?
Fifth disease doesn't usually cause complications. But it can in certain cases, such as:
- Pregnancy. Pregnant women who have been exposed to fifth disease should contact their family doctor. In about 5% of pregnant women, the baby develops severe anemia and miscarriage or stillbirth can occur. Treatment options include a blood transfusion to the unborn baby and medicines to treat the virus. If you are pregnant, talk to your doctor about whether you need to take any special steps to avoid fifth disease. The fifth disease infection does not cause birth defects or mental retardation.
- Weak immune system. People who have immune system problems, who have had transplants or who have cancer may need special treatment to help fight the infection.
- Chronic anemia. People who have sickle-cell disease or other types of chronic anemia have a problem with their blood that disrupts its ability to carry oxygen throughout their bodies. If they catch fifth disease, they can sometimes develop severe anemia that requires blood transfusions. (Note: Interestingly, these people rarely develop the typical fifth disease rash.)
Other. Fifth disease also has been linked to other diseases, including an infectious form of arthritis.
Questions to Ask Your Doctor
- I'm pregnant. What do I need to do to keep my baby safe?
- What treatment is best for me?
- How long will I be contagious?
- How long should I keep my child home from school?
- What can I do to make my child more comfortable?
- Should I tell my child's school that he/she has fifth disease?
- My rash keeps coming back when I spend time outside. Is that normal?
Copyright © American Academy of Family Physicians
This information provides a general overview and may not apply to everyone. Talk to your family doctor to find out if this information applies to you and to get more information on this subject.