Fifth Disease: Symptoms, Types, Causes and Treatment

Fifth disease, also known as "erythema infectiosum," is a common childhood viral illness that is often recognized by its distinctive red rash on the face. Despite its innocuous name, the disease can have varying presentations and, in some cases, lead to significant complications, especially in immunocompromised individuals. In this comprehensive guide, we will explore the symptoms, types, causes, and current treatment options for fifth disease, synthesizing evidence from recent research.

Symptoms of Fifth Disease

Fifth disease often begins like many other mild viral illnesses, but its hallmark is a bright red rash that appears on the cheeks, giving a "slapped cheek" appearance. However, symptoms can be diverse and vary based on age and immune status.

Symptom	Description	Commonality	Source(s)
Rash	"Slapped cheek" facial rash	High	3
Malaise	General feeling of discomfort	Moderate	3
Fever	Mild temperature elevation	Moderate	3
Joint pain	Aching joints, esp. in adults	Variable	3
Fatigue	Persistent tiredness	Moderate	1, 3
Anemia	Low red blood cell count	Low	2, 3

Table 1: Key Symptoms

The Classic Presentation

The most recognized symptom of fifth disease is the facial rash in children. This rash usually appears after several days of mild illness, which may include:

• Low-grade fever
• Sore throat
• Runny nose
• Headache

As these initial symptoms begin to resolve, the characteristic bright red rash appears on the cheeks. This may be followed by a lacy, pink rash on the arms, legs, and trunk. The rash can be itchy and may fluctuate in intensity, especially with changes in temperature or sunlight exposure 3.

Variations in Symptoms

Not all patients present with the classic rash. Adults, for example, are less likely to develop the facial rash but more likely to experience joint pain, particularly in the wrists, knees, and ankles. In some cases, the symptoms may be so mild that the infection goes unnoticed—these are called subclinical infections 3.

Complications and Special Cases

While fifth disease is usually mild, it can cause complications in certain groups:

• Immunocompromised individuals: Those with weakened immune systems, such as patients with leukemia, may develop severe or persistent anemia due to the virus's impact on red blood cell production 2.
• Pregnant women: Infection during pregnancy can, in rare cases, affect the fetus, warranting careful monitoring 3.

Types of Fifth Disease

Fifth disease may seem straightforward, but its clinical presentations can be categorized into distinct types based on patient age, immune status, and underlying health conditions.

Type	Population Affected	Unique Features	Source(s)
Classic	Children	"Slapped cheek" rash	3
Arthropathy	Adults	Joint pain, less rash	3
Chronic Anemia	Immunocompromised	Persistent anemia	2, 3
Subclinical	All ages	Few/no symptoms	3

Table 2: Types of Fifth Disease

Classic Fifth Disease

This type is most often seen in school-age children. The signature "slapped cheek" rash is typically preceded by mild symptoms such as fever and malaise. The rash can spread to the body and may last for several days to weeks 3.

Arthropathy Variant

Adults infected with parvovirus B19 are more likely to develop joint pain and swelling, particularly in the hands, wrists, knees, and ankles. This can be mistaken for other arthritic conditions. The rash, if present, is usually less prominent 3.

Chronic or Severe Disease

In individuals with weakened immune systems, such as those with leukemia or other immunodeficiencies, parvovirus B19 can cause chronic infection. This leads to persistent anemia, as the virus disrupts red blood cell production in the bone marrow. Such patients may not show the typical rash, making diagnosis more challenging 2, 3.

Subclinical Infection

A significant number of parvovirus B19 infections are subclinical—meaning the person has few or no obvious symptoms. These cases are often identified through serological testing during outbreaks or in epidemiological studies 3.

Causes of Fifth Disease

Understanding what causes fifth disease is essential for both prevention and management. The disease is primarily triggered by a specific virus, with unique characteristics that influence its spread and effects.

Cause	Agent/Mechanism	Notes	Source(s)
Parvovirus B19	Human parvovirus	Main and likely exclusive cause	2, 3
Transmission	Respiratory droplets	Most common route	3
Incubation	4-14 days (est.)	Viremia precedes rash	3
Risk factors	Immunosuppression	Severe complications possible	2

Table 3: Causes and Mechanisms

Parvovirus B19: The Culprit

Fifth disease is caused by infection with human parvovirus B19. This virus is highly specific to humans and is considered the sole cause of the disease. Outbreaks have consistently been linked to serological evidence of recent parvovirus B19 infection, even if direct detection is challenging due to the timing of the viremia 3.

How It Spreads

The virus is most commonly transmitted through respiratory secretions, such as saliva, mucus, or sputum, when an infected person coughs or sneezes. Less commonly, it can be spread through blood products or from mother to fetus 3.

The Course of Infection

• Incubation Period: The time from exposure to the onset of symptoms is typically 4–14 days. The virus is most contagious during the early phase, before the rash appears—by the time the rash develops, individuals are usually less contagious 3.
• Viremia: The virus circulates in the bloodstream during the incubation phase, then wanes as the immune system responds. This makes it difficult to detect the virus by direct testing after the rash appears 3.

Factors Increasing Severity

Certain groups are at higher risk for complications:

• Individuals with compromised immune systems can develop persistent infection and profound anemia 2.
• Pregnant women may risk fetal complications, emphasizing the need for awareness and possible monitoring during outbreaks 3.

Treatment of Fifth Disease

Most cases of fifth disease are mild and resolve without medical intervention, but certain situations require targeted treatment. The approach depends on the severity of symptoms and the patient’s underlying health status.

Treatment	Application	Effectiveness/Notes	Source(s)
Supportive care	Most cases	Symptom relief, self-limited illness	3
Immunoglobulin	Immunocompromised	Can reduce anemia, improve symptoms	2
Monitoring	At-risk groups	For complications (e.g., pregnancy)	2, 3
Antivirals	Not available	No approved antiviral for B19	3

Table 4: Treatment Approaches

Supportive Care

For otherwise healthy children and adults, treatment is generally supportive, as the infection is self-limited. Recommendations include:

• Rest and fluids
• Over-the-counter pain relievers (acetaminophen or ibuprofen) for fever or joint discomfort
• Antihistamines for itching, if the rash is bothersome

No specific antiviral medication is currently approved for parvovirus B19 infection 3.

Management in Immunocompromised Patients

In individuals with a weakened immune system, such as those with leukemia, fifth disease can lead to severe or persistent anemia. In such cases, treatment with intravenous immunoglobulin (IVIG)—which provides antibodies against parvovirus B19—has been shown to reduce viral levels and improve blood counts, at least temporarily 2. Ongoing monitoring and repeat treatments may be necessary due to the risk of relapse.

Special Considerations

• Pregnancy: Pregnant women who contract fifth disease should be monitored for potential fetal effects, including ultrasound monitoring for signs of fetal anemia or hydrops. In rare instances, specialized interventions may be required 3.
• Chronic Infection: In rare cases, especially among immunocompromised people, persistent infection may require repeated or ongoing immunoglobulin therapy 2.

Preventive Approaches

Currently, there is no vaccine for parvovirus B19. Preventive measures rely on good hygiene practices, such as frequent handwashing and covering coughs and sneezes, especially during outbreaks 3.

Conclusion

Fifth disease is a generally mild but sometimes complicated viral illness, especially in vulnerable populations. Recognizing its varied presentations and understanding its causes and treatments is essential for timely and effective care.

Key points:

• Fifth disease is primarily caused by human parvovirus B19 and is most common in children 2, 3.
• Typical symptoms include a "slapped cheek" rash, but adults may experience joint pain, and immunocompromised individuals may develop severe anemia 2, 3.
• The disease can present in multiple forms, from classic childhood rash to chronic anemia in at-risk patients 2, 3.
• Most cases require only supportive care, but targeted therapy with immunoglobulin is available for those with complications 2, 3.
• Awareness and monitoring are crucial for at-risk groups, including immunocompromised individuals and pregnant women 2, 3.

A clear understanding of fifth disease helps ensure that patients receive appropriate care, whether their illness is mild and fleeting or requires specialized intervention.