The Centers for Disease Control and Prevention (CDC) recently issued a Health Alert Network (HAN) advisory for the human parvovirus B19 across the United States. Although this virus is not new, the sudden surge in cases has raised concerns among healthcare providers, public health authorities, and the general public.
Parvovirus B19 is the only virus in its family that affects humans and is most common in children. It causes a disease commonly known as “slapped cheek disease” or “fifth disease,” which presents as a rash. The virus spreads primarily through respiratory droplets expelled when an infected person coughs or sneezes. Around 8 in 10 infected people don’t show any visible symptoms, making it easy for the virus to circulate unnoticed and potentially lead to widespread outbreaks.
According to the CDC, when parvovirus B19 hits strongly, it hits in two phases. The first phase of illness is characterized by symptoms of fever, myalgia, and malaise and develops approximately 7 days after infection. This phase lasts approximately 5 days. People with parvovirus B19 infection are most contagious during the first phase when viral loads in respiratory secretions and saliva are highest.
During the second phase of illness (approximately 7–10 days after the first phase), children often present with a characteristic facial rash (erythema infectiosum, or “slapped cheek” appearance), which may be followed by reticulated body rash or joint pain (arthralgia) 1–4 days later. In immunocompetent adults, the most common symptoms of parvovirus B19 disease typically occur during the second phase and include a reticular rash on the trunk and joint pain (arthralgia).
One of the problems in addressing the current surge in parvovirus B19 cases is the lack of routine surveillance. This makes it difficult to track the true prevalence of the virus and respond effectively to outbreaks. However, the CDC has issued an advisory, saying it’s received numerous reports of parvovirus B19 from parents whose children have the condition, particularly in children aged 5-9. The positivity rate in tests has jumped from around 15% in 2022 to 40% in 2024.
Adults in contact with infected children (typically parents and school workers) also have a high risk of infection. Many adults will experience joint pain that lasts a few weeks and goes away without major problems. Currently, there is no vaccine or specific antiviral treatment available for parvovirus B19. Management of the infection primarily focuses on supportive care, which may include hydration, pain relief, and treatment of any complications that arise.
For those at high risk of severe outcomes, early diagnosis, and monitoring are crucial. Per the CDC, you should seek medical help if you are pregnant and have been exposed to a person with suspected or confirmed parvovirus B19 or have signs and symptoms of the virus, or if you have a weakened immune system or a chronic hemolytic blood disorder and have signs and symptoms of parvovirus B19.
Even if you are not in one of these two categories, however, the CDC advises staying on alert and being aware of the symptoms and the risk.
Understanding Parvovirus B19
Parvovirus B19, also known as fifth disease or slapped cheek disease, is caused by the human parvovirus B19. This virus is most common in children, but it can affect individuals of all ages. The name “fifth disease” comes from the fact that it was the fifth of a group of rash-causing diseases of childhood to be identified. The virus spreads primarily through respiratory droplets, making it highly contagious.
The symptoms of parvovirus B19 infection can vary widely, with some individuals showing no visible signs of illness while others may experience a range of symptoms. In children, the typical presentation includes a red rash on the cheeks, giving the appearance of being slapped, followed by a lace-like rash on the trunk and limbs. Adults may experience joint pain, especially in the hands, wrists, knees, and ankles.
Risk Factors and Transmission
Children are most commonly affected by parvovirus B19, particularly those between the ages of 5 and 15. However, adults can also contract the virus, especially if they are in close contact with infected children. Pregnant women, individuals with weakened immune systems, and those with chronic hemolytic blood disorders are at a higher risk of developing complications from parvovirus B19 infection.
The virus is primarily transmitted through respiratory secretions, such as saliva or mucus, from an infected person. This means that the virus can easily spread in close quarters, such as schools, daycare centers, and households. It is important to practice good hygiene, such as frequent handwashing, to help prevent the spread of the virus.
Diagnosis and Treatment
Diagnosing parvovirus B19 infection can be challenging, as the symptoms can be similar to those of other viral illnesses. A healthcare provider may order blood tests to look for antibodies to the virus or perform other diagnostic tests to confirm the diagnosis. There is no specific antiviral treatment for parvovirus B19, so management focuses on relieving symptoms and preventing complications.
For most people, parvovirus B19 infection is a mild and self-limiting illness that resolves on its own without the need for medical intervention. However, in certain populations, such as pregnant women and individuals with underlying health conditions, the virus can lead to more serious complications. It is important to seek medical attention if you suspect you have been exposed to parvovirus B19 or if you develop symptoms of the infection.
Prevention and Public Health Measures
Preventing the spread of parvovirus B19 relies on good hygiene practices and public health measures. Individuals should wash their hands frequently, cover their mouths and noses when coughing or sneezing, and avoid close contact with individuals who are sick. Schools and daycare centers should implement policies to reduce the spread of the virus among children and staff.
Public health authorities play a crucial role in monitoring and responding to outbreaks of parvovirus B19. By tracking cases and implementing control measures, such as isolation and quarantine, they can help prevent the spread of the virus in the community. It is important for healthcare providers and the public to stay informed about the latest recommendations from the CDC and other health organizations.
In conclusion, the recent surge in cases of parvovirus B19, also known as fifth disease or slapped cheek disease, has raised concerns among healthcare providers and public health authorities. This highly contagious virus primarily affects children but can also infect adults, especially those in close contact with infected individuals. While most cases of parvovirus B19 are mild and self-limiting, certain populations are at a higher risk of developing complications. It is important to seek medical attention if you suspect you have been exposed to the virus or if you develop symptoms of infection. By practicing good hygiene and following public health recommendations, we can help prevent the spread of parvovirus B19 and protect our communities.
