Table of Contents

Component Description

Cytomegalovirus (CMV) antibody testing of stored sera specimens from NHANES III (1988–1994) was conducted to estimate the seroprevalence of CMV infection (CMV IgG) in participants age 6 and above. CMV IgG avidity and IgM were also measured in women age 12-49 years to estimate rates of primary infection.

Eligible Sample

Participants aged 6+ years from of NHANES III with stored sera (N = 21,648).

Description of Laboratory Methodology

CMV specific IgG was measured with an ELISA by Quest International, Inc., Miami FL. Sera with values near the ELISA cutoff (approx 7% of total) were confirmed with a second ELISA assay by bioMerieux, Inc., Durham, NC. When the results from these 2 tests disagreed (approx. 2% of total), an IFA from Bion International, Inc., was used and the result of the IFA was given as the final result.

CMV specific IgM was measured with an ELISA by bioMerieux, Inc., Durham, NC.

CMV IgG avidity was measured with an ELISA by bioMerieux, Inc., Durham, NC. Based on 2006 manufacture guidelines, 1= low avidity defined as RFV_INDEX < 0.8 and 2= High avidity defined as RFV_INDEX >= 0.8. IgG avidity is a measure of the overall strength of binding of the IgG antibody to the antigen. To determine high, low, or intermediate avidity, other cutpoints for RRV_INDEX may be used. See dataset 21A for RFV_INDEX values. The longer since primary infection the stronger the bond will be between IgG and the antigen. Low IgG avidity indicates a recent infection - so this infection is likely primary. High IgG avidity suggests that the primary infection occurred in the past. Those who are IgM positive and have high IgG avidity are likely experiencing a secondary infection (either a reactivation or reinfection).

Data Processing and Editing

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

Data Access: All data are publicly available.

Laboratory Quality Assurance and Monitoring

Commercial reagents were used for all CMV testing. All QC procedures recommended by the manufacturers were followed.

Analytic Notes

There are three variables:
CVP_IgG: (1=Positive, 2=Negative, 3= Equivocal)
CVP_IgM: (1= Positive, 2= Negative, 3= Equivocal)
CVP_IGGA: (1=low, 2=high)

References

Codebook and Frequencies

SEQN - Respondent sequence number

Variable Name:
SEQN
SAS Label:
Respondent sequence number
English Text:
Respondent sequence number.
Target:
Both males and females 6 YEARS - 150 YEARS

CVP_IGG - Serum CMV IgG

Variable Name:
CVP_IGG
SAS Label:
Serum CMV IgG
English Text:
Serum CMV IgG
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Positive 15477 15477
2 Negative 6162 21639
3 Equivocal 9 21648
. Missing 0 21648

CVP_IGM - Serum CMV IgM

Variable Name:
CVP_IGM
SAS Label:
Serum CMV IgM
English Text:
Serum CMV IgM
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Positive 127 127
2 Negative 5873 6000
3 Equivocal 74 6074
. Missing 15574 21648

CVP_IGGA - IgG Avidity

Variable Name:
CVP_IGGA
SAS Label:
IgG Avidity
English Text:
IgG Avidity
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 low 55 55
2 high 200 255
. Missing 21393 21648