CDC Issues Alert. There’s no vaccine or specific treatment for parvovirus B19.

(Verwellhealth, John Loeppky) — Last week, the Centers for Disease Control (CDC) published a health alert due to a significant uptick in parvovirus B19 cases and the presence of associated antibodies.

Parvovirus B19 is also known as Fifth disease or “slapped cheek syndrome” because of the characteristic facial rash.

William Schaffner, MD, a professor of preventive medicine and an infectious disease expert at Vanderbilt University School of Medicine, said the condition has existed since 1975.

“It’s called fifth disease, because early on in pediatrics when they were noting the various rash-causing illnesses such as measles and German measles, this was the fifth one on the list,” Schaffner told Verywell.

Most people infected with parvovirus B19 may show no symptoms at all, or mild symptoms such as throat, headache, cough, and temporary joint pain. Once the viral load has declined, a red rash may appear across the face, usually in children. The rash usually goes away in seven to 10 days.

The CDC’s alert about parvovirus B19 comes after a similar rise in Europe. While there is no cure or vaccine for the virus, more than 70% of those aged 40 and above have antibodies, according to the CDC. Those at the most risk of complications include children, pregnant people, and immunocompromised individuals.

Linda Yancey, MD, director of infection prevention at the Memorial Hermann Health System, said that parvovirus B19 is a public health concern that ebbs and flows.

“It’s one of these cyclic outbreaks where every three or four years, we’ll see a surge in cases. And that’s what we’re seeing right now. We’re up 15% from 2022 to 2024 and up 40% in June of 2024,” Yancey told Verywell.

Those percentages are associated with a rise in antibody detection rates in children aged five to nine. Yancey said the infection can spread quickly in daycare centers, and it’s best to keep children home if they show signs of respiratory illness.

Suellen Hopfer, PhD, an associate professor at the University of California, Irvine, said pregnant people should take additional precautions because the parvovirus B19 can be passed from the mother to the unborn child.

If a pregnant parent has a child who’s sick with parvovirus B19-like symptoms, Hopfer said, it’s best to see a doctor and get the child tested.

Since parvovirus B19 is a bone marrow pathogen, it could lead to severe anemia in rare cases, especially in people with cancer, unregulated HIV infection, or conditions like sickle cell disease.2 For those who are pregnant, the risk of fetal loss is between 5-10%, with the highest risk between weeks nine and 20 of pregnancy.

Yancey said that in severe cases, healthcare providers would monitor for red blood cell counts and put patients in protective isolation.

Preventing parvovirus B19 is similar to protecting yourself from general respiratory conditions. People who are at high risk of severe parvovirus B19 can consider wearing a mask around others.