High Varicella IgG Levels: Clinical Significance and Interpretation

Clinical Significance of High VZV IgG Levels

Individuals with verified positive VZV IgG levels, except bone marrow transplant recipients, may be considered immune to varicella, as recommended by the Centers for Disease Control and Prevention (CDC) 1, 2

Patients with high VZV IgG levels do not require Varicella Zoster Immune Globulin (VZIG) prophylaxis after exposure to varicella, according to the CDC guidelines 1, 2
Individuals with high VZV IgG are considered protected and do not need post-exposure prophylaxis even if they become immunocompromised later in life, unless they are bone marrow transplant recipients, as stated by the CDC 1, 3
Bone marrow transplant recipients are an exception and should be considered non-immune regardless of previous history of varicella or vaccination status, until they develop varicella or herpes zoster after transplantation, as recommended by the CDC 1, 2

Patients receiving monthly high-dose immune globulin intravenous (IGIV) (>400 mg/kg) are likely protected against varicella if the last dose was administered less than 3 weeks before exposure, according to the CDC guidelines 1, 4