The Centers for Disease Control and Prevention (CDC) has issued a health alert regarding a notable increase in cases of human parvovirus B19, also known as “fifth disease” or “slapped cheek” disease due to its distinctive rash. Reports indicate a surge in cases across various age groups, with 14 European countries observing unusually high case numbers. While the CDC does not directly track fifth disease in the U.S., it has noted an uptick in reported cases.
The alert highlights a significant rise in IgM antibody levels, indicating recent infections, which have surged from under 3% in 2022 to 10% in June. Notably, the incidence among children aged five to nine has jumped from 15% to 40% over the same period. Additionally, there has been an increase in parvovirus cases among pregnant individuals, including instances leading to severe fetal complications.
“While parvovirus B19 typically results in mild illness, it can pose greater risks to certain groups, such as pregnant women and those with weakened immune systems,” explained Dr. Andrew J. Carlson, medical director of the Division of Primary Care at Connecticut Children’s.
Understanding Human Parvovirus B19
Human parvovirus B19 is a common respiratory infection primarily affecting children, as they generally lack immunity. Dr. Susan Kline, a professor of medicine at the University of Minnesota, notes that about 50% of people are infected by age 20, which confers immunity for life. The virus spreads through respiratory droplets from coughs or sneezes.
The term “fifth disease” originates from a historical classification system used in the late 19th century to number common childhood rashes. Parvovirus B19 is the only disease from this system that retains its numerical reference.
Symptoms and Risks
Parvovirus B19 may present with no symptoms in some individuals, while others experience a range of symptoms including:
A distinctive red rash on the cheeks, often described as a “slapped cheek” appearance
- A lacy rash that extends from the trunk to the limbs
- Fever
- Headache
- Cough
- Sore throat
- Joint pain
While most cases are mild, complications can arise, particularly in individuals with weakened immune systems or specific blood disorders. Pregnant individuals are at risk of severe outcomes, such as miscarriage, if infected.
Current Surge and Its Causes
The reasons behind the current spike in parvovirus B19 cases are not entirely clear. Some experts suggest that the increase could be linked to decreased exposure during the COVID-19 pandemic due to social distancing and masking, which may have reduced immunity. Additionally, parvovirus B19 is known for cyclical outbreaks, which could explain the current surge as part of a natural pattern.
The return of children to school could also contribute to the spread, as respiratory illnesses often increase when children congregate.
Treatment and Prevention
There is no specific treatment for mild cases of parvovirus B19. Supportive care, including over-the-counter medications for fever and pain, is generally recommended. Severe cases may require more intensive treatments, such as red blood cell transfusions or IV immunoglobulin.
Preventative measures include practicing good hand hygiene and avoiding close contact with sick individuals. Pregnant individuals exposed to the virus should consult their healthcare provider for monitoring.
Dr. Kline advises parents to remain vigilant but not overly alarmed about the increase in cases. Awareness and early detection are key. “Be observant for symptoms and consult a healthcare provider if your child shows signs of the illness,” she said.
