The SARS-CoV-2 Spike Antibody Dilution test measures the concentration of IgG antibodies that target the spike protein of SARS-CoV-2, the virus that causes COVID-19. Unlike a simple positive/negative test, this method uses dilution to accurately detect even very high antibody levels, offering a clearer picture of your immune response.
What the Test Measures
This test quantifies the amount of spike-specific antibodies in your blood. These antibodies usually develop after:
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COVID-19 vaccination (Pfizer, Moderna, Novavax, and others)
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Previous COVID-19 infection
When antibody levels are very high—often after vaccination or a booster—standard antibody tests can reach their upper detection limit. Dilution testing “scales down” the sample so antibody levels can be measured precisely and reliably.
What Your Results Can Tell You
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Antibody presence: Confirms that your immune system has responded to either vaccination or infection.
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Relative antibody level: Higher dilution values generally reflect higher concentrations of antibodies.
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Immune recognition: Shows your body can recognize the spike protein, which may help mount a faster response upon re-exposure.
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Risk insight: People with higher antibody levels often have lower risk of severe COVID-19, though protection varies by individual and viral variant.
What These Results Do Not Show
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Exact protection: There is no universally defined antibody threshold that guarantees immunity.
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Timing of exposure: This test cannot determine when you were vaccinated or infected.
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Active infection: The dilution test does not diagnose current COVID-19 infection; other tests are needed for that purpose.
Why Dilution Testing Matters
Shortly after vaccination or booster shots, antibody levels can be so elevated that standard assays cannot measure them accurately. Diluting the sample ensures your result reflects the true concentration, rather than just reporting a “maximum.” This provides a more meaningful and actionable result for both patients and healthcare providers.
Summary
The SARS-CoV-2 Spike Antibody Dilution test offers a precise measurement of your antibody levels against the spike protein of COVID-19. Higher results typically suggest a stronger immune response from prior vaccination or infection. However, antibody levels alone do not guarantee full protection or lasting immunity. Continue to follow current public health recommendations, as antibodies are just one part of your body’s overall defense system.
SARS-CoV-2 Spike Ab Dilution
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