EBV Serology Panel Components
A standard EBV serology panel should include three essential antibodies: VCA IgM, VCA IgG, and EBNA-1 IgG 1.
Core Panel Components
The IDSA/ASM guidelines clearly specify that when heterophile antibody tests (Monospot) are negative or when you need to differentiate EBV from other causes of mononucleosis-like illness, you should order 1:
- VCA IgM (Viral Capsid Antigen IgM)
- VCA IgG (Viral Capsid Antigen IgG)
- EBNA-1 IgG (Epstein-Barr Nuclear Antigen IgG)
Interpretation Algorithm
These three markers allow you to distinguish infection stages 1:
Acute Primary Infection:
- VCA IgM positive (with or without VCA IgG)
- EBNA-1 IgG absent
Past Infection (>6 weeks):
- VCA IgG positive
- EBNA-1 IgG positive
- VCA IgM absent
Important timing note: EBNA-1 antibodies develop 1-2 months after primary infection and persist for life, so their presence indicates the infection occurred more than 6 weeks prior 1.
Additional Considerations
When to Add More Tests
Early antigen (EA-D) IgG is not part of the standard panel but may be useful in specific situations 2:
- Atypical serological patterns
- Suspected chronic active EBV infection (where VCA-IgG ≥1:640 and EA-IgG ≥1:160 are typical) 3
VCA IgG avidity testing can clarify ambiguous patterns, particularly when all three standard markers are positive simultaneously, which can occur during recent infection or reactivation 4, 5.
Common Pitfalls to Avoid
False-positive VCA IgM: Approximately 10% false-negative heterophile tests occur, especially in children under 10 years 1. Additionally, VCA IgM can cross-react during primary CMV infection (60.7% false-positive rate), so concomitant CMV testing is strongly recommended 6.
EBNA-1 antibody absence: About 5-10% of patients who have been infected with EBV fail to develop EBNA-1 antibodies despite true infection 1.
Isolated patterns: When only one marker is positive or results seem contradictory, consider IgG avidity testing or molecular methods (EBV DNA PCR) to clarify infection status 4, 5.
Specimen Requirements
Order serum in a clot tube, room temperature transport, ideally within 2 hours 1.
The three-marker panel (VCA IgM, VCA IgG, EBNA-1 IgG) provides >95% interpretability of EBV serological results 2 and represents the evidence-based standard for routine EBV diagnosis in immunocompetent patients.