• Component Description
• Eligible Sample
• Description of Laboratory Methodology
• Data Processing and Editing
• Laboratory Quality Assurance and Monitoring
• Analytic Notes
• References
• Codebook
  • SEQN - Respondent sequence number
  • SSEBV - Epstein Barr Virus result
  • SSEBVIND - Epstein Barr Virus index

National Health and Nutrition Examination Survey

2003-2004 Data Documentation, Codebook, and Frequencies

Epstein-Barr Virus (VCA IgG) - Serum (Surplus) (SSEBV_C)

Data File: SSEBV_C.xpt

First Published: June 2012

Last Revised: April 2022

Component Description

Among children ages 6-19 years who participated in NHANES between 2003 and 2004 and had stored serum samples available, Epstein-Barr virus (EBV) antibody testing was conducted. EBV VCA IgG antibody was measured using a commercial enzyme immunoassay kit.

Eligible Sample

Surplus sera from children aged 6 to 19 years who participated in NHANES years 2003 to 2004.

Description of Laboratory Methodology

25 μL of sample is required for each assay. Specimens, calibrators and controls are pre-diluted 1:21 prior to placing them in the test wells. Cut-off calibrator, controls and subject samples are diluted according to the specific test kit protocol, mixed briefly by vortex to assure good distribution of the sample in the diluent, and then transferred to the appropriately labeled wells and incubated. After washing the wells, conjugate is added with another incubation and wash step following. Substrate is added and allowed to incubate before the addition of stop/color reagent. The plates are read at an absorbance of 450 nm using a reference wavelength of 630 nm. EIA indices are calculated by hand using the formulas in the kit package insert. Data are recorded (1) as Positive (EIA index ≥ 1.10), Negative (EIA index <0.90), or Equivocal (EIA index ≥ 0.90 to 1.09), and (2) as the exact numeric EIA index. The sensitivity of the assay is 96.6% and the specificity is 97.7%.

Data Processing and Editing

Data were submitted after all the antibody testing was complete. The data were not edited.

Laboratory Quality Assurance and Monitoring

Commercial reagents were used for the EBV VCA IgG EIA antibody testing. All QA/QC procedures recommended by the manufacturer were followed.

Analytic Notes

The EIA indices have 4 categorical interpretations.
1. Negative. These samples have an EIA index <0.90.
2. Positive. These samples have an EIA index ≥1.10.
3. Equivocal. These samples have an EIA index ≥ 0.90 to 1.099.*
4. QNS. Quantity insufficient for testing. These samples were assigned an arbitrary index of missing.

*The only way to be certain if subjects with equivocal EIA antibody indices have been infected with EBV is to obtain another specimen from them. Since this is not practical and since this group is only a small fraction of the subjects tested (~0.05%), the cleanest approach to analyzing the data is to exclude them.

References

• Balfour HH Jr, Holman CJ, Hokanson KM, et al. A prospective clinical study of Epstein-Barr virus and host interactions during acute infectious mononucleosis. J Infect Dis 2005;192:1505-1512.
• Balfour HH, Jr, Hokanson KM, Schacherer RM, et al. A virologic pilot study of valacyclovir for infectious mononucleosis. J Clin Virol 2007;39:16-21.
• Diamedix VCA IgG Product Insert; Rev. 5, March 2008.
• Odumade OA, Hogquist KA, Balfour HH Jr. Progress and problems in understanding and managing primary Epstein-Barr virus infections. Clin Microbiol Rev 2011;24:193-209.

Codebook and Frequencies