Erythema Infectiosum

Erythema infectiosum, also known as fifth disease, is a common and highly contagious viral infection caused by parvovirus B19.

Causes and Risk Factors

The primary cause of erythema infectiosum is parvovirus B19. This virus is spread through respiratory droplets, such as those produced by coughing or sneezing, and can also be transmitted vertically from mother to fetus during pregnancy.

Symptoms

• A characteristic "slapped-cheek" rash on the face, which may appear 1-4 days after the onset of fever
• A lacy or reticular rash on the trunk and limbs, which may develop several days after the facial rash
• Mild fever, typically less than 102°F (39°C)
• Headache and fatigue
• Sore throat and runny nose
• Nausea and vomiting, especially in children

Diagnosis

Diagnosis of erythema infectiosum is typically based on clinical presentation, including the characteristic rash and symptoms. Laboratory tests, such as enzyme-linked immunosorbent assay (ELISA) or polymerase chain reaction (PCR), can confirm the presence of parvovirus B19.

Treatment

There is no specific treatment for erythema infectiosum, as it is a self-limiting illness. Supportive care, such as rest, hydration, and over-the-counter pain relievers (e.g., acetaminophen or ibuprofen), can help alleviate symptoms.

Complications

In rare cases, erythema infectiosum can lead to complications, including:

• Anemia, particularly in individuals with underlying hemolytic diseases (e.g., sickle cell disease)
• Aplastic crisis, a temporary cessation of bone marrow function
• Arthritis or arthralgia, especially in adults
• Infection during pregnancy, which can increase the risk of fetal anemia and other complications

Prevention

Prevention of erythema infectiosum involves avoiding close contact with individuals who have the infection, practicing good hygiene (e.g., frequent handwashing), and avoiding sharing food or drinks.

Prognosis

The prognosis for erythema infectiosum is generally excellent, with most individuals recovering within 1-3 weeks without any long-term consequences. However, in rare cases, complications can occur, especially in high-risk populations (e.g., those with underlying medical conditions or pregnant women).