Immunity & Titer Tests

This hub is for students, healthcare workers, caregivers, travelers, employers, and clinicians who need proof of immunity or post-vaccination verification. Core labs include MMR (measles/mumps/rubella) IgG, Varicella-Zoster IgG, Hepatitis B surface antibody (anti-HBs, quantitative) with HBsAg/anti-HBc for context when needed, Hepatitis A IgG, Tetanus/Diphtheria IgG (pertussis IgG has no standardized protection cutoff), and select neutralizing antibodytests (e.g., polio, rabies) where available. Results help document immunity for school/employment onboarding, travel, and clinical clarification—but final acceptance is set by the requesting institution.

What It Tests

“Immunity & titer testing” refers to blood (or occasionally neutralization) assays that indicate whether your immune system shows evidence of prior vaccination or infection for a specific disease.

Childhood & adult vaccines commonly checked:
Measles IgG, Mumps IgG, Rubella IgG (MMR); Varicella-Zoster IgG; Hepatitis B surface antibody (anti-HBs, quantitative) (with HBsAg/anti-HBc if status is unclear); Hepatitis A IgG; Tetanus/Diphtheria IgG(pertussis IgG lacks a validated correlate).
Special situations (as tests supports):
Pneumococcal/Hib/Meningococcal serotype-specific IgG; Rabies neutralizing antibodies (RFFIT) for high-risk occupations/programs.
Contextual testing:
SARS-CoV-2 antibody tests may reflect exposure/vaccination but should not be used to determine individual “immunity” or to guide boosters.
Caveats: Some assays (e.g., VZV after vaccination, pertussis) lack a universally accepted protective threshold; organizations may require vaccination records instead of, or in addition to, titers.

Key Tests

Test	Also Called (Synonyms)	What It Measures	Typical Prep	Specimen	Turnaround	Related Panels	Use Type (School/Employment/Travel/Clinical)	Timing Window / Seroconversion
Measles IgG	Rubeola IgG	Immunity after vaccine/infection	None	Serum	~1–3 d	Student/HCW Panel	School/Employment/Clinical	Check ≥4–6 weeks after MMR dose
Mumps IgG	—	Immunity after vaccine/infection	None	Serum	~1–3 d	Student/HCW Panel	School/Employment/Clinical	≥4–6 weekspost-MMR
Rubella IgG	—	Immunity (prenatal/school/HCW)	None	Serum	~1–3 d	Student/HCW/Prenatal	School/Employment/Clinical	≥4–6 weekspost-MMR; prenatal screening common
Varicella-Zoster IgG	VZV IgG	Immunity to chickenpox	None	Serum	~1–3 d	Student/HCW Panel	School/Employment/Clinical	≥4–6 weeks after vaccine; some EIAs less sensitive post-vaccine
Hepatitis B surface Ab (quant)	anti-HBs (quantitative)	Protective antibody after Hep B series	None	Serum	~1–3 d	HCW/Employment Panel	Employment/Clinical	Test 1–2 monthsafter series/booster; interpret with HBsAg/anti-HBc if unclear
HBsAg / anti-HBc	—	Current infection / past exposure	None	Serum	~1–3 d	Hep B Workup	Clinical	Use when anti-HBs negative or history unclear
Hepatitis A IgG	—	Immunity from prior infection/vaccine	None	Serum	~1–3 d	Travel Panel	Travel/Clinical	≥4 weeks after vaccination
Tetanus IgG / Diphtheria IgG	—	Antitoxin levels	None	Serum	~1–3 d	Adult Booster Panel	Employment/Clinical	Evaluate per policy; boosters per schedule
Pertussis IgG	—	Exposure marker; no validated protection threshold	None	Serum	~1–3 d	Adult Booster Panel	Clinical/Documentation	Institutions often require Tdap record, not titers
Polio neutralizing Ab	PRNT/Neutralization	Functional neutralizing antibodies	None	Serum	Varies	Travel/Occupational	Travel/Clinical	Specialized; confirm acceptance with authority
Pneumococcal/Hib/Meningococcal IgG	Serotype-specific	Response to vaccination (select risks)	None	Serum	~3–7 d	Special-Risk Panel	Employment/Clinical	Timing varies by series; serotype method notes apply
Rabies neutralizing Ab	RFFIT	Pre-exposure program titer	None	Serum	~7–14 d	Special-Risk Panel	Occupational/Clinical	Per public-health schedule/program
SARS-CoV-2 Ab (context only)	Spike/Neutralizing Ab	Exposure/vaccine response	None	Serum	~1–3 d	—	Clinical	Not for determining protection or guiding boosters

When to Test

School/college/immigration/employment onboarding where proof of immunity is required.
Healthcare workers (HCW): MMR, Varicella, Hep B anti-HBs (quant) ± TB screening per policy.
Travel to regions with specific requirements (e.g., polio, Hep A/B)—confirm the destination’s rules.
Post-vaccination checks: wait ≥4–6 weeks after MMR/Varicella and 1–2 months after Hep Bcompletion/booster.
Clinical clarification: unclear vaccine history; prenatal rubella/varicella status; immunocompromised host response.
Do not use IgM for immunity—IgM is for suspected acute infection.

How to Prepare

General: No fasting needed; bring vaccination records if available.
Post-vaccine timing: Test in the recommended window to allow seroconversion (avoid false negatives).
After IVIG/transfusion: Delay testing—passive antibodies can create false positives; follow clinician guidance.
Assay limits: For pertussis and some VZV assays (post-vaccine), there may be no reliable protective cutoff—institutions may accept vaccine records instead.
SARS-CoV-2: Antibody tests are not used to determine individual protection or to guide vaccination.
Specimens: Most tests use serum; neutralization assays (polio, rabies) may have special handling.

Interpreting Results

Qualitative vs quantitative: Know whether your report shows a number (e.g., anti-HBs mIU/mL) or positive/negative.
Hepatitis B algorithm: anti-HBs ≥ accepted threshold indicates protection; anti-HBs negative may require HBsAg/anti-HBc to clarify status and next steps per policy.
Vaccine vs natural infection: e.g., anti-HBs only → vaccination; anti-HBs anti-HBc → past infection; HBsAg→ current infection (not immunity).
Assay variability: Methods differ (EIA/CLIA/ECLIA). Varicella vaccine recipients may test negative on certain EIAs despite protection—records may suffice.
Immunocompromised/pregnancy: Titers can be lower or non-reactive even after vaccination—interpret with clinician support.
Institutional acceptance overrides: Schools/employers/travel authorities decide what counts (titer vs record vs repeat dose).

Related Conditions

Employment & Healthcare Onboarding
Travel Health & Exposure
Prenatal & Women’s Health
Infectious Disease Testing
General Health Tests

Bundles & Panels

Tetanus Titer Test – Measures IgG antibodies to tetanus toxin, indicating immunity level to tetanus from prior vaccination or exposure.
MMR Titer Test – Quantifies IgG antibodies to measles, mumps, and rubella; useful for confirming immunity to these common viral exposures.
Student Health Immunity Titers – Bundle of 4 IgG titer tests across 10 biomarkers (e.g. measles, mumps, rubella, varicella) ideal for assessing immunity status before school or work.
Immunity Panel – General immunity assessment measuring major immunoglobulins (IgG, IgM, IgA) and possibly common pathogen antibodies to assess immune competence.
Immunity Panel Plus – Expanded version of the basic Immunity Panel, includes additional titer testing (e.g. hepatitis B, other viral/bacterial exposures) for more comprehensive immunity profiling.

FAQs

Which titers do schools or hospitals usually require?
Commonly MMR IgG, Varicella IgG, and Hep B surface antibody (quantitative); some also request TB screening(infection screen).

How soon after vaccination should I check my titer?
Typically ≥4–6 weeks after MMR/Varicella and 1–2 months after Hep B series/booster.

My Hep B surface antibody is negative—what does that mean?
You may need additional evaluation (HBsAg/anti-HBc) and follow the institution’s protocol for boosters or repeat series.

Can a positive antibody test replace vaccination records?
Sometimes, but not always—acceptance varies by school/employer/travel authority.

Do I need a pertussis titer for Tdap?
Usually no; there’s no standardized protective cutoff for pertussis IgG. Institutions often require documented Tdap.

Why is my varicella titer negative after two doses?
Some assays are less sensitive in vaccine recipients; many institutions accept documented 2-dose vaccination.

Do I need a COVID-19 antibody test to prove immunity?
No. These are not recommended to assess protection or guide vaccination decisions.

I had IVIG or a transfusion—can I test now?
Delay titers; passive antibodies can cause false positives. Ask your clinician when to test.

Can I use IgM to prove immunity?
No. IgM is used to assess acute infection, not immunity.

Who decides if my titer is acceptable?
Your school, employer, or travel authority—the lab report alone doesn’t guarantee acceptance.

References

CDC/ACIP — U.S. immunization schedules and serologic testing guidance (MMR, Varicella, Hep A/B, Tdap, polio).
Immunize.org — Professional education on vaccine records vs titers and documentation requirements.
WHO — Technical guidance on correlates of protection and serology.
IDSA — Guidance on serologic testing and post-exposure/occupational considerations.
Public-health resources — Rabies RFFIT programs, polio neutralization testing notes.
SARS-CoV-2 serology statements — not to guide vaccination or determine immunity.

Last reviewed: September 2025 by Ulta Lab Tests Medical Review Team

Need to be sure of your immunization status?

Ulta Lab Testing offers accurate and reliable immunity and titer tests to help you make an informed decision about your health. We offer titer testing and immunity detection for a wide variety of conditions, including:

Get the peace of mind that comes with knowing your immunization status.

Our titer and immunity detection tests provide reliable results to ensure your immunizations are up to date. So, if you're unsure about your immunization status, turn to Ulta Lab Testing for accurate and dependable titer tests and immunity detections. Order today!

Please see the list below for lab testing for conditions that may be impacted by changes in your immunity.

All Immunity and Titer Tests

COVID-19 / Coronavirus Antibody

Immunity

Immunoglobulins

Titer

Tuberculosis - QuantiFERON Test

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An Overview of Immunoglobulins

A Guide to Immunity Detection and Titer Testing - What You Need to Know

Tuberculosis and TB Lab Testing - What You Need to Know

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All Immunity and Titer Tests

COVID-19 / Coronavirus Antibody

Immunity

Immunoglobulins

TB and QuantiFERON Tests (Immunity & Titer)

Titer

Key Lab Tests for Immunity Detection

A large section of the population in the United States is at risk of catching preventable diseases since vaccinations are not as readily available as most people think. Many regions across the country don't have the healthcare facilities required to administer vaccines to the population of nearby areas. Vaccination is crucial, especially at a time like this when the Coronavirus pandemic is spreading across the globe. On the other hand, we need protection from other everyday ailments that could be prevented.

Even if you received all of your vaccinations when you were young, you might no longer have adequate immunity to the diseases you were vaccinated against. That is why everyone in the country needs titer testing for immunity detection. The serological testing will help your healthcare provider determine your actual immunization status to various diseases. With the right information, you and your physician can make adequate plans to improve your health moving forward. ... See more

What Is Immunity Detection?

Titer testing and immunity detection help you and your healthcare provider understand what illnesses you do and do not have immunity against. For example, even if you have been immunized against a particular disease, it doesn't mean that the body will retain immunity past a few years. A sample of your blood will be used to test for an immune response during an antibody test, also known as a titer or immunity test. During the test, your blood sample is exposed to the bacteria or virus you're testing immunity for to see how your blood sample responds. If your immunity is low, you should update your shots. You should stay up-to-date on all of your vaccines to be protected from preventable diseases in the long run.

The Risks of Low Immunity

Lack of vaccination is the most common risk for low immunity. Your body won't have a good immune response to a particular disease or virus when you haven't gotten the vaccine for that particular condition. Even if you have contracted that particular disease before, it doesn't mean you will have a strong immune response to the condition the next time you come into contact with it.

If you were vaccinated against a particular condition a long time ago, your level of immunity could lower over time. This is another risk of low immunity. For example, most of us get important vaccines at the beginning of our lives. We will lose immunity over time if we don't update our shots when required. Lastly, people with immunodeficiencies may experience issues in retaining proper immune responses over time. Most of the time, the body of such people may not have the necessary strength to fight some of these diseases. These people should get antibody testing to determine what vaccinations they need to update immediately.

The Diseases You Could Test for Immunity

Scientists have formed plenty of serological testing possibilities for various health conditions. There is an immune response test for a wide variety of diseases starting from measles to diphtheria. If you are worried about a particular condition, you can always ask your physician about vaccination programs against that particular condition. There are times when you may have to work with people who have chickenpox or be at a higher risk of developing tetanus at work. Make sure your physician knows about whatever situation you are currently experiencing so that they can come up with the right immunization plan for you.

The Signs of Low Immunity Detection

A person is more likely to contract a disease if they have an impaired immune system or an inadequate immune response to that particular condition. For example, you are always at risk of contracting a disease that you are not protected against. If you contract a condition that you are not protected against, you will show signs consistent with that particular disease.

There isn't a way to determine your immune response to a particular condition unless you get antibody testing done or contract the disease. That is why you need to get the tests done without delay instead of having to worry about how your body will react to the virus or bacteria later on.

How Is Your Immune Level Measured?

You should get a lab test done to measure your immune response to various diseases and conditions. It's the only way to determine the immunity level in your body before you contract the particular disease. With an immunity or titer test, your blood will be drawn at a patient service center. The blood specimen will be sent to the nearest national laboratory to test for antibodies to the particular diseases you want to measure immunity against. If your specimen doesn't have an immune response, you aren't immune to the particular condition.

Lab Tests to Monitor Immunity Levels

There are numerous lab tests for different conditions that you may need to check your immunity for. At Ulta Labs, we offer titer testing and immunity detection for a wide variety of conditions, including:

Get Your Immunity Testing with Ulta Lab Testing!

Do you want to determine your immunization status? If so, you need immunity detection and titer testing. Ulta Labs offers accurate and reliable tests to help you make an informed decision about your health.

Here are some reasons to choose Ulta Lab Tests:

You don't need a referral from a physician
Your results are secure and confidential
Results are available in 24-48 hours for most tests
You don't need health insurance
100% satisfaction guarantee
Affordable pricing

Take control of your health today with immunity lab tests from Ulta Lab Tests.

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