A highly contagious respiratory illness that causes a “slapped cheek” rash is on the rise, health officials warn.
The CDC sounded the alarm this week about a rise in cases of parvovirus B19, a respiratory virus that spreads from person to person through breathing, coughing or sneezing.
They warned that in just two years, cases have increased by almost two-thirds in children aged five to nine. And authorities have also noted a rise in infections in pregnant women.
While most cases cause only mild symptoms — a bright red rash on the cheeks — and resolve on their own, pregnant or immunocompromised patients may be at risk for serious complications such as anemia, miscarriages and stillbirth.
It’s not clear what’s behind the surge, but the CDC warning comes after European authorities reported unusually high numbers of parvovirus B19 in 14 countries during the first quarter of the year.
Parvovirus B19 causes a characteristic “slap-face” rash in children. Once the rash appears, patients are no longer contagious.
Parvovirus B19 is a respiratory virus that most commonly spreads in late winter, spring, and early summer.
“Historically, people who work in schools and have close contact with children (e.g., child care workers and teachers) have been at high occupational risk for infection,” CDC officials wrote in a statement Tuesday. health alert.
About seven in ten Americans have detectable antibodies by age 40, indicating they were previously infected.
According to CDC data, the proportion of people who had antibodies from a recent infection increased from three percent in 2022-2024 to 10 percent in June 2024.
And the biggest increase was seen in children aged five to nine, which rose from 15 percent in 2022-2024 to 40 percent in June.
Many patients never develop symptoms, but those who do often notice a mild fever, muscle aches, cough, sore throat and general fatigue. As the disease progresses, children develop the characteristic “slapped cheek” rash, which can spread to other parts of the body.
“Children and adults with parvovirus B19 are no longer contagious once the characteristic facial rash appears,” CDC officials wrote.
Most patients need rest and fluids, but a small group of those who are pregnant or immunocompromised may have more serious consequences.
The CDC warned that if a pregnant woman becomes infected, the virus can be transmitted to the fetus and cause fetal anemia, miscarriage or stillbirth in about 5 to 10 percent of cases. These complications are most common between weeks 9 and 20 of pregnancy.
People with weakened immune systems, such as cancer patients, may be at risk for aplastic anemia, a condition that occurs when the bone marrow can no longer produce enough oxygen-carrying red blood cells. If left untreated, aplastic anemia can lead to uncontrolled bleeding and death.
The CDC did not suggest what might be behind the rise in parvovirus B19 cases, but recommended general precautions such as washing hands, staying away from sick people and wearing a mask in public.
