Natural Immunity Blood Test

What is Immunity Due to Natural Infection?

Natural immunity occurs when your immune system successfully fights off an infection and develops long-lasting protection against future infections from the same pathogen. It is caused by the production of specific antibodies that remain in your bloodstream after recovering from diseases like Hepatitis B, measles, or chickenpox. The Hepatitis B Core Antibody Total test is the most important test for confirming natural immunity to Hepatitis B virus.

RECOMMENDED TEST Hepatitis B Core Antibody, Total
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What causes natural immunity?

Natural immunity is caused by your immune system's response to an actual infection with a virus or bacteria. When a pathogen like Hepatitis B virus, varicella-zoster virus (chickenpox), or measles virus enters your body, your immune system produces specialized proteins called antibodies that target and destroy the invader. These antibodies remain in your bloodstream for years or even your entire lifetime, providing ongoing protection against future infections from the same pathogen.

What is the best test for natural immunity?

The Hepatitis B Core Antibody Total test is the most important test for confirming natural immunity to Hepatitis B because it detects Anti-HBc antibodies that only appear after actual infection, not vaccination. When this test shows positive results along with Hepatitis B surface antibodies (Anti-HBs), it confirms your body successfully fought off the virus and developed lasting protection. Different antibody tests are used for other infections - for example, varicella antibody tests for chickenpox immunity or measles antibody tests for measles immunity - but the Hepatitis B Core Antibody test is essential for determining if you have natural Hepatitis B immunity versus vaccine-induced immunity.

When should I get tested for natural immunity?

You should get tested if you suspect you had a past infection and want to confirm your immunity status before traveling to high-risk areas, starting a new healthcare job that requires immunity documentation, considering pregnancy and need to know your protection levels, or determining whether you need vaccination. Testing is also important if you were exposed to someone with an infectious disease and want to know if you're already protected, or if you're planning to donate blood or organs and need complete immunity records.

What are the symptoms of natural immunity?
Natural immunity itself does not cause symptoms because it is a protective state that exists after you have recovered from an infection. However, the original infection that triggered your immunity may have caused symptoms like fever, fatigue, body aches, rash, or organ-specific symptoms depending on the disease. Once you recover and develop natural immunity, you typically feel healthy and normal. The only way to confirm natural immunity is through blood testing, as you cannot feel or see antibodies in your system.
Who is at risk for lacking natural immunity?
People who have never been infected with a particular pathogen lack natural immunity to that disease. This includes individuals who were vaccinated but never had the actual infection, babies and young children who have not yet been exposed to common childhood diseases, people with limited exposure to infections due to good hygiene or isolated environments, and individuals with weakened immune systems who may not develop strong immunity even after infection. Healthcare workers, international travelers, and pregnant women should verify their immunity status because lack of protection can pose serious health risks in certain situations.
What happens if I do not have natural immunity?
If you lack natural immunity to a disease, you remain vulnerable to infection when exposed to that pathogen. For serious diseases like Hepatitis B, lack of immunity means you could develop acute or chronic infection, which can lead to liver damage, cirrhosis, liver cancer, or liver failure. Without natural immunity to other diseases like measles or chickenpox, you face risks of severe complications including pneumonia, brain inflammation, birth defects (if infected during pregnancy), or hospitalization. Fortunately, vaccination can provide effective protection when natural immunity is absent.
Can natural immunity be diagnosed with a blood test?
Yes, natural immunity is diagnosed through antibody blood tests that detect specific proteins your immune system produced during a past infection. These tests measure immunoglobulins (antibodies) such as IgG that indicate long-term immunity. The Hepatitis B Core Antibody Total test specifically identifies natural immunity to Hepatitis B by detecting antibodies that only appear after actual infection, not vaccination. Blood tests are the gold standard for confirming immunity status because antibodies are not visible or detectable through physical examination or symptoms alone.
How is lack of immunity treated?
Lack of immunity is typically addressed through vaccination, which stimulates your immune system to produce protective antibodies without causing actual disease. For Hepatitis B, a three-dose vaccine series provides immunity in over 90% of healthy adults. Other vaccines are available for measles, chickenpox, rubella, and many other diseases. If you are exposed to a disease before being vaccinated, post-exposure prophylaxis (such as immunoglobulin injections) can sometimes provide temporary protection. Regular booster shots may be needed for certain vaccines to maintain immunity levels throughout your lifetime.
How can I prevent loss of natural immunity?
Natural immunity to most viral infections like Hepatitis B, measles, and chickenpox typically lasts for life and does not require maintenance. However, maintaining a healthy immune system through proper nutrition, adequate sleep, regular exercise, stress management, and avoiding immunosuppressive medications (when possible) helps preserve your immune function. Some infections may require booster vaccinations if antibody levels decline over time. Regular health checkups and antibody testing can verify your immunity status and determine if any boosters are needed to maintain protection.
What natural remedies help maintain immunity?
While natural remedies cannot replace immunity testing or vaccination, certain lifestyle practices support overall immune function. Eating a nutrient-rich diet with plenty of fruits, vegetables, lean proteins, and whole grains provides vitamins C, D, E, zinc, and selenium that support immune health. Getting 7-9 hours of quality sleep each night allows your immune system to regenerate. Regular moderate exercise, staying hydrated, managing stress through meditation or yoga, and avoiding smoking and excessive alcohol help maintain robust immune function. Probiotic-rich foods like yogurt and fermented vegetables support gut health, which plays a crucial role in immunity.
How’s this work?
Getting your blood test with us is easy, private & backed by the power of science.

Long story short:
  1. In the test options, use the filters or search box to narrow your choices and find the test you want.
  2. If you need a hand navigating through options, text our super friendly support team at 754-799-7833, and we'll provide tailored suggestions to help you find the ideal test.
  3. Once your order is placed, we’ll create your doctor’s lab order remotely, without any need for you to make a trip to a doctor in person or to talk to the doctor. Expect to receive your doctor’s lab order right in your inbox. It will also be in your patient portal if you need to find it later. We’ll also include instructions regarding fasting and other requirements for your test. Your patient portal will be auto-created hassle-free during checkout.
  4. If this is your first time ordering, you'll be prompted to create a password for instant login access to your patient portal. It's a quick way to conveniently access your orders and results whenever you want.
  5. When you’re ready, visit one of our 4,000 locations. Just bring your ID – no printing or faxing of your lab order is needed, as your order and details will already be in the lab system.
  6. Note that most lab locations don’t accept walk-ins, so it’s best to book an appointment in advance. Don’t worry – we’ll provide detailed instructions along the way.
  7. You’ll get your results via email & SMS and dive into understanding your body better. Yup, that easy!
  8. If you have any questions, please text us at 754-799-7833 or email support@privatemdlabs.com and we'll gladly help you.
How do I know which test to get?
In the test options, find the test you want. If you’re not sure which test to get, we can lend a hand in finding the right option.

Just text or call us at 754-799-7833, email us at support@privatemdlabs.com, and we'll gladly help you. We've got your back and reply quickly.
Is it possible to make changes to my lab order if I made a mistake with the name, date of birth, or any other details?
Absolutely! We totally understand that errors can happen. No worries, we're here to help you.

Just reach out to us via text at 754-799-7833 or shoot us an email at support@privatemdlabs.com. Remember to include your order number and let us know the correct information you’d like to update. Our awesome team will jump right in and make sure everything is sorted out and accurate for you.

There are no changes necessary if your address is wrong on the requisition though. We don’t mail anything out.

Our lab requires an address to be listed to generate an order.
Do you accept health insurance?
Only HSA & FSA is accepted.

Our services are strictly self-pay and cannot be submitted to your health insurance provider except for Health Savings Accounts or Flexible Savings Accounts.

This policy applies to all insurance companies, including federal health insurance programs like Medicare.

If you have any questions, please text us at 754-799-7833 or email support@privatemdlabs.com.
Can I cancel my order?
Yes.

We get it – sometimes your needs change.

As long as your samples haven’t been collected yet, we’re happy to help you cancel your order.

If you have any further questions, please text us at 754-799-7833 or email support@privatemdlabs.com.

You can read more about our cancellation policy here.
How can I find a lab location near me?
During the ordering process, you’ll be able to select a specific lab near you, with no strings attached! You can switch it up later easily and visit any of our authorized locations as long as it’s the same lab company you selected your test for (Quest Diagnostics or Labcorp).

Before you proceed with your order, feel free to browse through all our lab locations here. This will give you the peace of mind of knowing that there's a lab nearby your home, office or your favorite gym.

If you have any questions, please text us at 754-799-7833 or email support@privatemdlabs.com and we'll gladly help you.
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* Regular blood test results (e.g., CBC) typically start arriving the next business day after sample collection. More complex tests, such as hormone panels, may take up to 10–15 business days due to their complexity.

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Hepatitis B Core Antibody, Total
What's included
Fast & easy, results by email & SMS
No need to visit a doctor
Private & confidential
No insurance needed
Results explained
No extra fees paid at the lab

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