Title: Epstein-Barr virus (VCA IgG)
Contact Number: 1-866-441-NCHS
Years of Content: 2003 - 2004
First Published: June, 2012
Access Constraints: None
Use Constraints: None
Geographic Coverage: National
Subject:Epstein-Barr virus VCA IgG antibodies measured by enzyme immunoassay
Record Source: NHANES 2003 - 2004
Survey Methodology: NHANES 2003 - 2004 is a stratified multistage probability sample of the civilian non-institutionalized population of the U.S.
Medium: NHANES Web site; SAS transport files
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.
Surplus sera from children aged 6 to 19 years who participated in NHANES years 2003 to 2004.
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 were submitted after all the antibody testing was complete. The data were not edited.
Commercial reagents were used for the EBV VCA IgG EIA antibody testing. All QA/QC procedures recommended by the manufacturer were followed.
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.
|Code or Value||Value Description||Count||Cumulative||Skip to Item|
|4||Quantity not sufficient||0||2870|