Immunization status or previous exposure to diseases is often assessed using serology. This testing can evaluate protection from diseases such as pertussis, hepatitis A, hepatitis B, measles, mumps, rubella, chickenpox, shingles, and polio. Serologic investigation is especially useful for individuals with missing or incomplete vaccination records. Immunization status may be needed for various reasons, such as to inform decisions about vaccination, employment, school admission, or acceptance into an assisted living residence. Although laboratory test results can provide evidence of vaccination or exposure, there is no laboratory test available to definitively establish immunity.
Quick Answers for Clinicians
The CDC provides up-to-date information for individuals and healthcare providers. This information is comprehensive and includes specific vaccination schedules for children 18 years or younger and adults 19 years or older, catch-up strategies for individuals who have missed vaccines, vaccine administration guidelines, safety information, recommendations for the evaluation and vaccination of patients who have no (or questionable) vaccination records or who have been vaccinated outside of the United States, and other educational materials.
Serology testing can be used to detect the presence of neutralizing antibodies to poliovirus. However, in most cases, revaccination is recommended instead of serology testing when a patient has an unknown vaccination status. The appropriate ARUP test to detect poliovirus antibodies is Poliovirus (Types 1, 3) Antibodies (2014107). Detailed information about the CDC’s recommendations for poliovirus vaccination can be found on the CDC’s website.
All pregnant patients should be evaluated for evidence of immunity to rubella and varicella-zoster viruses. Pregnant patients without evidence of immunity to these viruses should be vaccinated immediately after delivery.
For all other diseases, the CDC recommendations for the use of serology testing for pregnant individuals with unknown vaccination status are the same as for all adults with unknown vaccination status. Serology testing can be used to determine immunization status, but revaccination is recommended.
Serology testing is used to detect antibodies that indicate previous vaccination or exposure to diseases. The results of these tests can be used to determine a medically appropriate vaccination schedule.
Refer to the following ARUP Consult topics for disease-specific information, such as detailed laboratory testing information and links to additional CDC resources: Bordetella pertussis, Viral Hepatitis, Measles Virus, Mumps Virus, Rubella Virus, and Varicella Zoster Virus.
Indications for Testing
Serology testing is a useful tool to determine immunization status or previous exposure to infectious agents, but testing should not be a barrier to the vaccination of individuals, especially those who are at high risk for exposure to vaccine-preventable diseases. Disease-specific serology testing recommendations can be found below.
Individuals who have complete medical records do not need serology testing to determine immunization status. However, these individuals should follow all CDC-recommended vaccination schedules for any missing vaccinations.
Hepatitis A Virus
Generally, if patients do not know whether they have been vaccinated against hepatitis A virus (HAV), the CDC recommends revaccination without serology testing. However, serology testing can be performed to determine immunization status and whether or not vaccination is required. Prevaccination testing is most likely to be cost-effective for patients who were born or lived for an extended period in a geographic area with high or intermediate HAV prevalence.
Postvaccination serologic testing is not necessary after routine vaccination. However, testing for anti-HAV antibodies may be useful in some patients, including people with HIV infections and other immunocompromised individuals.
Hepatitis B Virus
Generally, if patients do not know whether they have been vaccinated against HBV, the CDC recommends revaccination and serologic testing for hepatitis B surface antigen (HBsAg). For healthcare providers (HCPs), serology testing to avoid unnecessary revaccination may be cost-effective.
Postvaccination serology testing is recommended for HCPs who are at high risk for occupational exposure to HBV and should be performed 1-2 months after vaccination. HCPs with a documented exposure to HBV should receive postexposure serology testing if they are unvaccinated or incompletely vaccinated or if they do not have documented proof of immunity.
Measles, Mumps, and Rubella
Generally, if patients do not know whether they have been vaccinated against measles, mumps, and rubella, the CDC recommends revaccination without serology testing. Serology testing can be performed to determine immunization status and help determine whether vaccination is required. Patients with well-documented, age-appropriate vaccination against measles, mumps, and rubella should not be revaccinated, even if serology test results show a negative or equivocal titer. Prevaccination testing for HCPs without adequate presumptive evidence for immunity is generally not necessary. Serology testing is not recommended for HCPs with two documented doses of the measles, mumps, and rubella (MMR) vaccine.
Postvaccination and postexposure serology testing are not recommended for measles, mumps, and rubella.
Pertussis
If the pertussis vaccination status of a patient or HCP is unknown, age-appropriate vaccination (or revaccination) should be performed. Serology testing is not an accurate measure of immunity because serologic correlates of protection have not been well established. Prevaccination, postvaccination, and postexposure serology testing are not recommended.
Varicella
Generally, if patients do not know whether they have been vaccinated against varicella (chickenpox), the CDC recommends revaccination. However, serology testing before vaccination is likely to be cost-effective in a healthcare setting. If a person has received two documented doses of the varicella vaccine, serology testing is not recommended.
Postvaccination and postexposure serology testing are not recommended.
Polio
Serologic testing to determine prior immunization to poliovirus is not recommended by the CDC. If the vaccination status of a patient or HCP is unknown, age-appropriate vaccination should be performed without serology testing.
Rabies
Serology testing may be performed to monitor rabies immune status in individuals who have a high occupational risk of rabies exposure (eg, veterinarians) or after a confirmed occupational exposure. In some cases, serology testing may be useful to monitor the immune response in a person undergoing postexposure prophylaxis treatment.
ARUP Laboratory Tests
(Refer to the ARUP Consult Bordetella pertussis topic for more information)
Qualitative Immunoblot
Semi-Quantitative Enzyme-Linked Immunosorbent Assay/Qualitative Immunoblot
(Refer to the ARUP Consult Viral Hepatitis topic for more information)
Qualitative Chemiluminescent Immunoassay
(Refer to the ARUP Consult Viral Hepatitis topic for more information)
Quantitative Chemiluminescent Immunoassay
(Refer to the ARUP Consult Measles Virus topic for more information)
Semi-Quantitative Chemiluminescent Immunoassay
(Refer to the ARUP Consult Mumps Virus topic for more information)
Semi-Quantitative Chemiluminescent Immunoassay
(Refer to the ARUP Consult Rubella Virus topic for more information)
Semi-quantitative Chemiluminescent Immunoassay
(Refer to the ARUP Consult Varicella-Zoster Virus topic for more information)
Semi-Quantitative Chemiluminescent Immunoassay
Semi-Quantitative Serum Neutralization
References
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CDC - Vaccines and immunizations
U.S. Department of Health and Human Services, Centers for Disease Control and Prevention. Vaccines and immunizations. [Last reviewed: Feb 2021; Accessed: Jun 2022]
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CDC - Healthcare providers (vaccine)
U.S. Department of Health and Human Services, Centers for Disease Control and Prevention. Healthcare providers/professionals. [Last reviewed: Nov 2020; Accessed: Jun 2022]
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CDC - Recommended Immunization Schedules for Children and Adolescents Aged 18 Years or Younger
U.S. Department of Health and Human Services, Centers for Disease Control and Prevention. Advisory Committee on Immunization Practices recommended immunization schedule for children and adolescents aged 18 years or younger – United States, 2019. [Last reviewed: Feb 2019; Accessed: Jun 2022]
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CDC - Adult Immunization Schedule
U.S. Department of Health and Human Services, Centers for Disease Control and Prevention. Recommended adult immunization schedule for ages 19 years or older, United States, 2020. [Last reviewed: Feb 2022; Accessed: Jun 2022]
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CDC - Catch-up immunization, 4 mo-18yrs
U.S. Department of Health and Human Services, Centers for Disease Control and Prevention. Catch-up immunization schedule for persons aged 4 months-18 years who start late or who are more than 1 month behind, United States, 2020. [Last reviewed: Feb 2022; Accessed: Jun 2022]
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CDC - Healthcare vaccine administration
U.S. Department of Health and Human Services, Centers for Disease Control and Prevention. Healthcare providers/professionals: vaccine administration. [Last reviewed: May 2018; Accessed: Jun 2022]
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CDC - Healthcare vaccine safety
U.S. Department of Health and Human Services, Centers for Disease Control and Prevention. Healthcare providers/professionals: vaccine safety. [Last reviewed: May 2016; Accessed: Jun 2022]
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CDC - Evaluation and vaccination of persons vaccinated outside of the U.S. who have no (or questionable) vaccination records
U.S. Department of Health and Human Services, Centers for Disease Control and Prevention. Vaccine recommendations and guidelines of the ACIP: Table 9-1. Approaches to evaluation and vaccination of persons vaccinated outside the United States who have no (or questionable) vaccination records. [Last reviewed: Jul 2022; Accessed: Aug 2022]
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CDC - Global immunization: polio
U.S. Department of Health and Human Services, Centers for Disease Control and Prevention. Global immunization: polio vaccination in the U.S. [Last reviewed: Aug 2022; Accessed: Aug 2022]
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28081056
Marin M, Patel M, Oberste S, et al. Guidance for assessment of poliovirus vaccination status and vaccination of children who have received poliovirus vaccine outside the United States [published correction appears in MMWR Morb Mortal Wkly Rep. 2017;66(6):180]. MMWR Morb Mortal Wkly Rep. 2017;66(1):23-25.
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ACIP - Guiding Principles for Development of ACIP Recommendations for Vaccination during Pregnancy and Breastfeeding
Advisory Committee on Immunization Practices (ACIP). Guiding principles for development of ACIP recommendations for vaccination during pregnancy and breastfeeding. Centers for Disease Control and Prevention. [Last updated: Apr 2008; Accessed: Jun 2022]
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22108587
Advisory Committee on Immunization Practices. Immunization of health-care personnel: recommendations of the Advisory Committee on Immunization Practices (ACIP). MWR Recomm Rep. 2011;60(RR-7):1-45.
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CDC - Rabies serology
U.S. Department of Health and Human Services, Centers for Disease Control and Prevention. Rabies serology. [Last reviewed: Apr 2016; Accessed: Sep 2022]
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ACOG Committee Opinion No. 741: maternal immunization. Obstet Gynecol. 2018;131(6):e214-e217. [Reaffirmed: 2021]
Medical Experts
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NOTE: Laboratory tests cannot establish immunity to the diseases included in this topic; the laboratory tests discussed here can only provide evidence of vaccination or previous exposure.