From the Guidelines
Measles immunity is determined through blood tests that measure measles-specific IgG antibodies, and if you lack adequate antibodies, vaccination with the MMR vaccine is recommended, with a standard regimen consisting of two doses given at least 28 days apart. The testing for measles immunity is crucial, especially for high-risk groups such as healthcare workers, international travelers, and students at post-secondary educational institutions, as well as for women planning pregnancy who are unsure of their immunity status 1.
- If you were born before 1957, you're generally considered immune due to widespread measles exposure during that era.
- For those born after 1957, documented evidence of two MMR vaccine doses, laboratory confirmation of immunity, or documentation of measles infection provides proof of immunity.
- Certain high-risk groups should have documentation of immunity or receive vaccination, and testing is particularly important for these groups.
- The antibody test is reliable because measles infection or proper vaccination typically confers lifelong immunity through the production of these specific antibodies that protect against future infection 1. The most recent and highest quality study, from 2014, recommends that healthcare personnel born before 1957 who lack laboratory evidence of measles, mumps, and/or rubella immunity or laboratory confirmation of disease should be considered for vaccination with 2 doses of MMR vaccine 1.
From the Research
Measles Immunity Testing
To determine measles immunity and the need for the Measles, Mumps, and Rubella (MMR) vaccine, several tests can be conducted. These include:
- Measles virus (MeV) neutralizing antibody tests to measure the level of antibodies against measles in the blood 2
- Immunoglobulin G (IgG) antibody avidity tests to assess the strength of the immune response 2
- Cell-mediated immunity (CMI) analyses to evaluate the presence of T-cell memory 2
- Multiplex flow immunoassays, such as the BioPlex 2200 MMRV IgG multiplex flow immunoassay, to detect IgG-class antibodies to measles, mumps, rubella, and varicella-zoster viruses 3
- Immunofluorescence assays (IFAs) to detect antibodies against measles, mumps, and varicella-zoster viruses 3
Interpretation of Test Results
The results of these tests can help determine an individual's immunity to measles and the need for vaccination. For example:
- A measles virus neutralizing antibody level of <8 mIU/mL indicates seronegativity, while a level of 8-120 mIU/mL indicates low antibody levels 2
- A positive result on a multiplex flow immunoassay or IFA indicates the presence of IgG-class antibodies against measles, mumps, rubella, or varicella-zoster viruses 3
- The sensitivity and specificity of these tests can vary, and negative results may not always indicate a lack of immunity 3
Clinical Applications
These tests can be used in various clinical settings, such as:
- Evaluating the immune status of healthcare workers to ensure compliance with national standards and state laws 3
- Determining the need for vaccination in individuals with uncertain or incomplete vaccination histories 3
- Assessing the effectiveness of vaccination campaigns and monitoring measles immunity in populations 2