• Component Description
• Eligible Sample
• Description of Laboratory Methodology
• Laboratory Quality Assurance and Monitoring
• Data Processing and Editing
• Analytic Notes
• References
• Codebook
  • SEQN - Respondent sequence number
  • WTSSMMPP - Surplus spec MMRV weights prepandemic
  • SSMEASQ - Measles IgG Antibody MBA Quantitative
  • SSMEASQC - Measles IgG Antibody MBA Comment
  • SSMEASI - Measles IgG Antibody MBA Interpretation
  • SSMUMPQ - Mumps IgG Antibody MBA Quantitative
  • SSMUMPQC - Mumps IgG Antibody MBA Comment
  • SSMUMPI - Mumps IgG Antibody MBA Interpretation
  • SSRUBQ - Rubella IgG Antibody MBA Quantitative
  • SSRUBQC - Rubella IgG Antibody MBA Comment
  • SSRUBI - Rubella IgG Antibody MBA Interpretation
  • SSVARMQ - Varicella IgG Antibody MBA Quantitative
  • SSVARMQC - Varicella IgG Antibody MBA Comment
  • SSVARMI - Varicella IgG Antibody MBA Interpret
  • SSVARGI - Varicella gpELISA Interpretation
  • SSVARINT - Varicella Overall Interpretation

National Health and Nutrition Examination Survey

2017-March 2020 Data Documentation, Codebook, and Frequencies

Measles, Mumps, Rubella, & Varicella – Serum (Surplus) (P_SSMMRV)

Data File: P_SSMMRV.xpt

First Published: December 2025

Last Revised: NA

Component Description

The NHANES program suspended field operations in March 2020 due to the coronavirus disease 2019 (COVID-19) pandemic. As a result, data collection for the NHANES 2019-2020 cycle was not completed and the collected data are not nationally representative. Therefore, data collected from 2019 to March 2020 were combined with data from the NHANES 2017-2018 cycle to form a nationally representative sample of NHANES 2017-March 2020 pre-pandemic data. These data are available to the public. Please refer to the Analytic Notes section for more details on the use of the data.

Measles, mumps, rubella, and varicella are highly contagious, viral, vaccine-preventable diseases. Varicella is caused by varicella-zoster virus (VZV). Serological testing for antibodies among NHANES participants has been a primary means for assessing susceptibility to measles, mumps, rubella, and varicella and determining the impact of the respective vaccination programs in the U.S. The last survey cycle for which seroprevalence was evaluated was 2009-2010 (MMRV_F ; Lebo, et. al., 2015). Assessing seroprevalence serves to document progress toward achieving related Healthy People 2030 goals. In addition, documenting trends in immunity is necessary to estimate duration of protection in the U.S. population.

Eligible Sample

Examined participants aged 6-59 years were eligible.

Description of Laboratory Methodology

Stored serum specimens were processed, stored, and shipped to the National Center for Immunization and Respiratory Diseases Laboratories.

Measles, mumps, rubella, and varicella IgG Luminex multiplex bead assay (MMRV-MBA)

The method used a lab developed measles, mumps, rubella, and varicella IgG Luminex multiplex bead assay (MMRV-MBA) for the detection and quantitative determination of IgG antibody (Smits, et. al., 2012). Measles whole virus antigen (WVA), mumps WVA, rubella WVA, and VZV glycoprotein were coupled to carboxylated magnetic beads loaded with different fluorescent dyes, allowing for pathogen-specific beads to be quantified separately and simultaneously. When these viral antigen beads are brought into contact with a serum specimen, antigen specific antibody (if present) will bind to the antigen on the solid phase forming antigen-antibody complexes. Excess antibody is removed by washing. This is followed by the addition of goat anti-human IgG (heavy chain specific) conjugated with R-phycoerythrin that then binds to the IgG-antigen complexes. The excess conjugate is removed by washing. The mean fluorescence intensity (MFI) value, which is proportional to the amount of antibody in the serum, is determined fluorometrically at a wavelength of 580nm. Antibody concentration is interpolated by comparing MFI of the unknown sample to a known reference serum standard (RUBI 1-94 or 97/648, National Institute for Biological Standards and Control). Antibody concentrations for samples are reported as either international unit (IU) concentrations or arbitrary unit (AU) concentrations, depending on the calibration of the reference serum standards. For this study, antibody concentrations were reported as mIU/mL for measles, AU/mL for mumps, IU/mL for rubella, and mIU/mL for varicella (VZV). Seroprotection cutoffs for MMRV-MBA have been established for measles and rubella at 200 mIU/ml and 10 IU/ml, respectively. No correlate of protection has been established for mumps and varicella, but cutoffs for seropositivity were established during assay validation.

The lab method for this component in the NHANES 2017–March 2020 cycle was different compared to the 2009–2010 cycle.

Varicella-zoster virus gpELISA

If varicella (VZV) testing results were equivocal or negative after MMRV-MBA, the sample was retested on the VZV gpELISA (gpELISA). The gpELISA is an in-house assay designed to identify individuals with an adaptive immune response to VZV from prior infection or vaccination using serum specimens (Sauerbrei and Wutzler, 2012; Weinmann, et. al., 2008). The assay relies on the binding of VZV glycoprotein (gp) and normal tissue control antigen (NT) to ELISA plates. Serum is added to coated plates where antigen specific antibody will bind forming complexes, these complexes are detected using goat anti-human IgG alkaline phosphatase conjugate antibody and a colorimetric substrate with a wavelength absorbance of 405nm. The optical density (OD) of the non-specific binding observed for NT is subtracted from the OD of the specific binding observed for gp. Positive, negative and equivocal OD cut-off ranges were determined during assay validation.

There were no changes to the lab method for this component in the NHANES 2017–March 2020 cycle compared to the 2009–2010 cycle.

Laboratory Quality Assurance and Monitoring

During MMRV-MBA testing, the concentration of 3 controls (including at least one positive and one negative for each analyte), was tracked on a Levey-Jennings plot following each run. If more than one control per analyte exceeded three standard deviations from the mean, the run was considered to have failed, and the samples were repeated at the end of the study. At completion of the MBA testing all samples that tested negative or equivocal for varicella (VZV) were repeated using the gpELISA. The gpELISA included a high positive, low positive, and negative control as well as a reagent blank for each run. Any samples that were discordant between MBA and gpELISA were classified based off the results from the gpELISA assay. Additionally, a randomized 10% of MBA samples which included samples from all test plates was independently diluted and repeated after completion of the original testing for quality assurance purposes.

Data Processing and Editing

Data were received after all analyses were complete. The data were reviewed. Incomplete data or improbable values were sent to the performing laboratory for confirmation.

Derived variables were created in this data file:

SSMEASI

Measles IgG Antibody Multiplex Bead Assay Interpretation (SSMEASI) was coded as 1 (positive) when SSMEASQ was greater than or equal to 200 mIU/mL and was coded as 2 (negative) when SSMEASQ was less than 200 mIU/mL.

SSMUMPI

Mumps IgG Antibody Multiplex Bead Assay Interpretation (SSMUMPI) was coded as 1 (positive) when SSMUMPQ was greater than or equal to 46 AU/mL and was coded as 2 (negative) when SSMUMPQ was less than 46 AU/mL.

SSRUBI

Rubella IgG Antibody Multiplex Bead Assay Interpretation (SSRUBI) was coded as 1 (positive) when SSRUBQ was greater than or equal to 10 IU/mL and was coded as 2 (negative) when SSRUBQ was less than 10 IU/mL.

SSVARMI

Varicella (VZV) IgG Antibody Multiplex Bead Assay Interpretation (SSVARMI) was coded as 1 (positive) when SSVARMQ was greater than 80 mIU/mL, coded as 2 (negative) when SSVARMQ was less than 48 mIU/mL, and coded as 3 (equivocal) when SSVARMQ was greater than or equal to 48 mIU/mL and less than or equal to 80 mIU/mL.

SSVARGI

Varicella (VZV) gpELISA Interpretation (SSVARGI) was coded as missing when SSVARMI was positive, as 1 (positive) when the gpELISA had an OD value greater than or equal to 0.300, coded as 2 (negative) when the gpELISA had an OD value was less than or equal to 0.200, and coded as 3 (equivocal) when the gpELISA had an OD value greater than or equal to 0.201 and less than or equal to 0.299. 

SSVARINT

Varicella (VZV) Overall Interpretation (SSVARINT) was coded based on the combined results of SSVARMI and SSVARGI. SSVARINT was coded as 1 (positive) when SSVARMI was 1 (positive). When SSVARMI was 2 (negative) or 3 (equivocal), SSVARINT was coded based on the results of SSVARGI as 1 (positive) when SSVARGI was 1 (positive), as 2 (negative) when SSVARGI was 2 (negative), and as 3 (equivocal) when SSVARGI was 3 (equivocal):

SSVARMI	SSVARGI	SSVARINT
Positive	N/A	Positive
Equivocal	Positive	Positive
Equivocal	Equivocal	Equivocal
Equivocal	Negative	Negative
Negative	Positive	Positive
Negative	Equivocal	Equivocal
Negative	Negative	Negative

Analytic Notes

The COVID-19 pandemic required suspension of NHANES 2019-2020 field operations in March 2020 after data were collected in 18 of the 30 survey locations in the 2019-2020 sample. Data collection was cancelled for the remaining 12 locations. Because the collected data from 18 locations were not nationally representative, these data were combined with the previous cycle (2017-2018) to create a 2017-March 2020 pre-pandemic data file. A special weighting process was applied to the 2017-March 2020 pre-pandemic data file. The resulting sample weights in the present file should be used to calculate estimates from the combined cycles. These sample weights are not appropriate for independent analyses of the 2019-2020 data and will not yield nationally representative results for either the 2017-2018 data alone or the 2019-March 2020 data alone. Please refer to the NHANES website for additional information for the NHANES 2017-March 2020 pre-pandemic data.

Refer to the 2017-2018 and 2019-2020 Laboratory Data Overviews for general information on NHANES laboratory data.

There are over 800 laboratory tests performed on NHANES participants. However, not all participants provided biospecimens or enough volume for all the tests to be performed. Additionally, availability of specimens for surplus projects is lower than for other laboratory tests performed on NHANES participants. The specimen availability can also vary by age or other population characteristics. Analysts should evaluate the extent of missing data in the dataset related to the outcome of interest as well as any predictor variables used in the analyses to determine whether additional re-weighting for item non-response is necessary.

Please refer to the NHANES Analytic Guidelines and the on-line NHANES Tutorial for details on the use of sample weights and analytic issues.

Subsample Weights

The analytes included in this dataset were measured in examined participants aged 6-59 years. Special sample weights are required to analyze these data properly. Specific sample weights for this subsample, WTSSMMPP, are included in this data file and should be used when analyzing these data. The sample weights created for this file used the examination sample weight, i.e., WTMECPRP, as the base weight. The base weight was adjusted for additional nonresponse to these lab tests and re-poststratified to the population total using sex, age, and race/Hispanic origin. Participants who were part of the eligible population but who did not provide a serum specimen, or did not have sufficient volume of biospecimens, or who did not give consent for their specimens to be used for future research are included in the file, but they have a sample weight assigned “0” in their records.

Demographic and Other Related Variables

The analysis of NHANES laboratory data must be conducted using the appropriate survey design and demographic variables. The NHANES 2017-March 2020 Pre-Pandemic Demographics File contains demographic data, health indicators, and other related information collected during household interviews as well as the sample design variables. The recommended procedure for variance estimation requires use of stratum and PSU variables (SDMVSTRA and SDMVPSU, respectively) in the demographic data file.

This laboratory data file can be linked to the other NHANES data files using the unique survey participant identifier (i.e., SEQN).

Detection Limits

Three variables are provided for each of these analytes. The variable name ending in “Q” provides the analytic results for that analyte. Samples falling above the range of the standard curve were reported as the maximum of the reportable range. Samples falling below the minimum range of the standard curve were reported as 0 (less than 0 is an artifact of subtracting background). The variable name ending in “I” provides an interpretation of the seropositivity status for that analyte. The variable name ending in “QC” indicates whether the result was above the range of the standard curve: the value “0” means the result was below the maximum of the reportable range of the standard curve, “1” indicates the result was above the maximum of the reportable range of the standard curve.

The reportable range for the MMRV-MBA assay was:

Variable Name	Analyte Description	Reportable Range
SSMEASQ	Measles IgG Antibody Multiplex Bead Assay Quantitative Result (mIU/mL)	0 – 100,000 mIU/mL
SSMUMPQ	Mumps IgG Antibody Multiplex Bead Assay Quantitative Result (AU/mL)	0 – 700,000 AU/mL
SSRUBQ	Rubella IgG Antibody Multiplex Bead Assay Quantitative Result (IU/mL)	0 – 5,000 IU/mL
SSVARMQ	Varicella (VZV) IgG Antibody Multiplex Bead Assay Quantitative Result (mIU/mL)	0 – 500,000 mIU/mL

The VZV gpELISA has no upper or lower limit of optical density.

References

• Lebo E., Kruszon-Moran D.M., Marin M., Bellini, W.J., Schmid S., Bialek S.R., et al. Seroprevalence of measles, mumps, rubella and varicella antibodies in the United States population, 2009–2010. Open Forum Design Infect Dis. (2015) Feb 20;2(1).
• Sauerbrei A., Wutzler P. Serological detection of varicella-zoster virus-specific immunoglobulin G by an enzyme-linked immunosorbent assay using glycoprotein antigen. J Clin Microbiol. (2006) 44(9):3094-7.
• Smits G.P., van Gageldonk P.G., Schouls L.M., van der Klis F.R., Berbers G.A. Development of a bead-based multiplex immunoassay for simultaneous quantitative detection of IgG serum antibodies against measles, mumps, rubella, and varicella-zoster virus. Clin Vaccine Immunol. (2012) 19(3):396-400.
• Weinmann S., Chun C., Mullooly J.P., Riedlinger K., Houston H., Loparev V.N., et al. Laboratory diagnosis and characteristics of breakthrough varicella in children. J Infect Dis. (2008) Mar 1;197 Suppl 2:S132-8.

Codebook and Frequencies