Fifth disease is so-named because of its fifth-place status on the list of once-common, rash-producing childhood diseases. That list includes rubella, measles, scarlet fever and Duke’s disease (an infection no longer recognized by today’s doctors). Unlike its past peers, however, fifth disease is still going strong, infecting half the population. Today, it’s just as much a rite of passage for children as chicken pox is. And like chicken pox, fifth disease, also known as parvovirus infection or erythema infectiosum, is best had in your youth.
Although about 20 percent of all cases occur without symptoms, the disease is often more severe and longer lasting in adults than in kids. Pregnant women who catch fifth disease are also at risk for fetal complications.
Fifth disease is an infection caused by human parvovirus B19. It spreads like the flu, by direct contact with an infected person’s respiratory secretions, such as droplets from a sneeze or cough. It can also be spread by sharing drinking cups or utensils.
A mild illness in children, it resembles a cold during the first five to 10 days of symptom onset. Soon after, a lacy, pink facial rash appears on the cheeks, giving the illness its nickname, slap-cheeked disease. The rash can also affect the arms, trunk, thighs and buttocks, and it may come and go for up to three weeks.
Instead of getting the rash, adults typically have sore, swollen joints that can last for a few days to several months. As a result, doctors sometimes misdiagnose the disease as arthritis. A simple blood test, however, can reveal if it’s fifth disease. Luckily, once you’ve had the virus, you become immune to it.
Fifth disease is only contagious before symptoms appear, making it nearly impossible to dodge. Pregnant women at risk may try to evade fifth disease by limiting their exposure to children ages 5 to 15—the age group most commonly infected. Extra precautions should be taken in winter and spring when most outbreaks occur.
If you’re a mother-to-be who isn’t sure if you’re at risk for fifth disease, your doctor may recommend the blood test to determine whether you’re immune to the disease or were recently infected.
If a pregnant woman becomes infected, her fetus can develop severe anemia. Fetal anemia can lead to heart failure, low birth weight, preterm birth or miscarriage. Fortunately, these complications occur in fewer than 5 percent of infected mothers-to-be.
To ensure a safe pregnancy while infected with human parvovirus B19, your doctor may perform ultrasounds to monitor the baby.
An ultrasound can show, for example, if the fetus has edema, or swelling of the body tissues, which signals heart failure.
No vaccine or treatment exists for fifth disease, but acetaminophen or ibuprofen can help ease joint pain.