Parvovirus B19—The ‘Slapped Cheek’ Virus Spreads Across the U.S.

Medically reviewed by Dr Itender Pal Singh

As the world recovers from the COVID-19 pandemic, a new health threat is making headlines across the United States: human parvovirus B19, commonly known as the “slapped cheek” virus. This highly contagious virus primarily affects children and is known for its characteristic cheek rash. However, recent reports suggest that adults, particularly those with certain health conditions, may also be at significant risk.

What is Parvovirus B19?

Parvovirus B19, often referred to as “fifth disease,” is a common childhood illness that ranks fifth on the list of childhood diseases known to cause a rash. The virus is easily spread through respiratory droplets, making it highly transmissible, especially among children. Despite its widespread nature, many people are unfamiliar with this virus, often confusing it with canine parvovirus, which affects dogs but is entirely different.

The Current Situation

Recent data from the Centers for Disease Control and Prevention (CDC) indicate a worrying trend: the incidence of parvovirus B19 is on the rise in the U.S. After several European countries reported unusually high cases earlier this year, the CDC issued a warning that the virus is spreading rapidly across the nation. Blood tests from commercial laboratories have shown a significant increase in the presence of IgM antibodies, which are produced in response to the virus. The proportion of people with these antibodies has surged from just over 3 percent during 2022–2024 to 10 percent in June 2024.

Why the Sudden Surge?

One theory behind this sudden increase in cases is the so-called “immunity gap” caused by the COVID-19 pandemic. With social distancing measures and reduced human contact over the past few years, many individuals, particularly children, may not have been exposed to the virus, resulting in a larger population lacking immunity. This has created a perfect storm for the virus to spread now that people are once again interacting more freely.

Who is Most at Risk?

Children: The Primary Targets

Children aged 4 to 10 are the most susceptible to parvovirus B19. The virus spreads quickly in school settings, where one infected child can easily transmit it to classmates. According to the latest CDC data, there has been a notable spike in cases among children aged 5 to 9, with the proportion of these children testing positive for IgM antibodies more than doubling from 15 percent during 2022–2024 to 40 percent in June 2024.

Adults: A Hidden Danger

While parvovirus B19 is typically mild in children, it can pose serious risks to certain adults. Pregnant women, for instance, are at risk of transmitting the virus to their fetus, which can lead to severe complications such as fetal anemia or even pregnancy loss. Additionally, individuals with sickle cell anemia, those undergoing blood transfusions, or those who are immunocompromised (such as cancer patients or organ transplant recipients) are at heightened risk of severe complications, including aplastic crisis, a condition where the bone marrow suddenly stops producing red blood cells.

Symptoms

Mild Yet Distinctive Signs

For most people, parvovirus B19 causes either no symptoms or mild, flu-like symptoms that resolve on their own. The illness typically progresses in two phases. The first phase occurs approximately seven days after exposure, during which fever, muscle aches, headache, cough, and sore throat may develop. This is the period when the virus is most contagious.

The ‘Slapped Cheek’ Rash

In children, the second phase of the illness is marked by the appearance of a distinctive red rash on the cheeks, often referred to as the “slapped cheek” rash. This rash may also spread to other parts of the body, including the chest, back, buttocks, arms, and legs. Adults, on the other hand, are more likely to experience joint pain during this phase rather than the rash.

The Impact on High-Risk Groups

Pregnancy and Parvovirus B19

Pregnant women are particularly vulnerable to parvovirus B19. The virus can cross the placenta and infect the fetus, potentially leading to severe anemia and other complications. In some cases, fetal transfusions may be necessary to address the anemia. The CDC has noted an increase in reports of parvovirus B19 infections among pregnant women, making it crucial for expectant mothers to be aware of the risks and take preventive measures.

Immunocompromised Individuals

For those with weakened immune systems, such as patients undergoing chemotherapy, organ transplant recipients, or individuals with HIV, parvovirus B19 can cause severe and life-threatening complications. These individuals may experience a sudden drop in red blood cell production, leading to aplastic crisis, which often requires hospitalization.

Treatment and Management

Symptomatic Relief

There is currently no specific antiviral treatment for parvovirus B19, and most cases resolve on their own. Treatment primarily focuses on alleviating symptoms. Acetaminophen can be used to reduce fever and relieve headaches, while nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen can help manage joint pain and swelling.

Supportive Care

In addition to medication, supportive care measures such as staying hydrated and getting plenty of rest are essential for recovery. In severe cases, especially for those with underlying health conditions, medical intervention may be necessary to manage complications.

Prevention: How to Protect Yourself and Others

No Vaccine, But Precautions Can Help

Unfortunately, there is no vaccine available to prevent parvovirus B19 infection. However, following standard precautions for respiratory viruses can help reduce the risk of transmission.

Hygiene Practices

The CDC recommends covering your mouth and nose with a tissue when you cough or sneeze, and if a tissue isn’t available, using your elbow instead of your hands. Frequent handwashing is crucial, especially in environments such as schools and healthcare facilities where the virus can spread easily.

Cleanliness Matters

Regularly cleaning frequently touched surfaces like doorknobs, handrails, and countertops can also help limit the spread of the virus. For those who develop symptoms, it’s essential to stay home and avoid contact with others until the rash appears, indicating that the person is no longer contagious.

As parvovirus B19 continues to spread across the U.S., it’s important to stay informed and take preventive measures to protect yourself and your loved ones. While the virus is usually mild, it can pose serious risks to certain individuals, particularly pregnant women, children, and those with compromised immune systems. By following good hygiene practices and being aware of the symptoms, we can help curb the spread of this highly contagious virus.

SOURCES–

Harrison manual of internal medicine

About Parvovirus B19. Centers for Disease Control and Prevention. 

Fifth Disease. Nationwide Children’s Hospital

Healthy Habits: Coughing and Sneezing. Centre for Disease Control and Prevention

About Handwashing. Centre for Disease Control and Prevention