9347. Parvovirus B19, IgG antibodies

The IgG test for parvovirus B19 allows one to determine immunity after infection. It is important for assessing risks during pregnancy planning, during outbreaks of infections in groups, or when examining patients with anemia of unknown origin.

Parvovirus B19 is the infectious agent that causes fifth disease (erythema infectiosum) in children and can have serious consequences in adults. It has a particular affinity for erythroid cells in the bone marrow and can disrupt hematopoiesis.

In most immunocompetent individuals, the infection is mild or asymptomatic. However, in pregnant women, individuals with immunodeficiencies, or hemolytic diseases, parvovirus can cause:

• Aplastic crises (in individuals with sickle cell anemia or thalassemia).
• Chronic anemia in immunosuppressed patients.
• Intrauterine infection of the fetus with the development of non-immune hydrops fetalis, especially if infection occurs before the 20th week of pregnancy.

IgG test:

IgG antibodies appear 1-2 weeks after infection and persist for a long time, often for life. The presence of IgG indicates a past infection and immunity.

The test is used for:

• Assessing the immune status of women before or during early pregnancy.
• Searching for the source of infection during an outbreak in a child care or school setting.
• Retrospective risk assessment in case of contact with sick individuals.
• Examination of patients with anemia or suspected viral hematopoietic suppression.

Detection of IgG to parvovirus B19 confirms immunity. In the absence of IgG (seronegativity), the patient is considered susceptible to infection. If a recent infection is clinically suspected, additional testing for IgM or PCR for viral DNA is recommended.

• Women planning a pregnancy or during early pregnancy – to eliminate the risk of fetal infection.
• Pregnant women who have had contact with infected individuals or work in children's groups.
• Children and adults with symptoms of erythema infectiosum (rash, fever, joint pain).
• Patients with anemia, thrombocytopenia, or leukopenia of unknown origin.
• Weakened immunosuppressed patients – with prolonged or unexplained cytopenias.
• As part of the TORCH screening – to identify a less common but important infection that can cause embryofetopathy.

• Venous blood

In order to exclude factors that may affect the test results, we recommend to follow the preparation rules: