Parvovirus B19 Resurgence in U.S.: The ‘Slapped Cheek’ Virus

Federal health authorities are cautioning healthcare providers to remain vigilant for a respiratory virus called parvovirus B19, as infection rates rise in the United States.

Parvovirus B19, a long-standing virus, typically manifests mild or asymptomatic symptoms in children and healthy adults. However, it can pose severe complications for pregnant individuals, immunocompromised patients, or those with specific hematologic conditions.

In a recent health advisory issued by the Centers for Disease Control and Prevention, a surge in the number of individuals testing positive for antibodies of parvovirus B19, indicating recent infections, has been noted, particularly among children aged 5 to 9.

This year, health authorities across 14 European nations have also reported an unusually high incidence of cases, as highlighted by the CDC.

Infections typically peak during late winter, spring, and early summer, with minor outbreaks occurring every three to four years. The current spread coincides with the start of the new school year.

Here are essential facts about the virus.

How does it spread, and how do I know if I’m infected?

Parvovirus B19 transmission occurs through respiratory droplets, blood, or vertical transmission from mother to fetus during pregnancy. (Note: Canine parvovirus is distinct from parvovirus B19 and does not transfer between pets and humans.)

While many infected individuals remain asymptomatic, symptoms vary by age for those who do exhibit signs.

In children, initial symptoms resemble flu-like manifestations, including fever, headache, and cough, with contagiousness peaking during this phase, lasting several days. Subsequently, children might develop a facial rash, hence the moniker “slapped-cheek disease.”

Conversely, adults commonly experience joint pain as a predominant symptom, lasting from days to weeks.

How concerned should I be?

For most, recovery occurs without specific treatment, except when the virus impacts the bloodstream, leading to complications like severe anemia.

A parvovirus B19 infection typically does not pose a direct threat to pregnancy or the fetus. Nevertheless, in rare instances, fetal anemia or miscarriage may occur as a result of an infection.

Individuals with compromised immune systems or certain hematologic conditions face a higher risk of severe anemia due to infection, necessitating proactive management.

Most adults develop immunity to the virus over time. As per the CDC, approximately 50% of adults possess detectable antibodies by age 20, increasing to over 70% by age 40.

How can I ensure safety?

Adhering to standard hygiene practices, such as regular hand-washing and disinfecting frequently touched surfaces, is essential in preventing viral spread, akin to other respiratory infections.

Individuals at heightened risk should promptly notify healthcare professionals if exposed to a child presenting with high fever followed by a rash, emphasizes Dr. Kawsar Talaat, an infectious disease specialist from Johns Hopkins Bloomberg School of Public Health.

“Remaining calm is crucial. Most infections are mild and resolve spontaneously,” Talaat notes. “This serves as a preemptive advisory for healthcare providers to anticipate heightened infection rates and attend to vulnerable populations accordingly.”

NPR’s Pien Huang provided reporting for this article.