Lyme Evidence Sheet

Reviewed 2026-07-24

What is modified two-tier Lyme testing?

Modified two-tier testing uses two FDA-cleared antibody tests in sequence rather than an immunoblot. The full sequence and final laboratory interpretation still matter.

What the evidence says

  • FDA cleared new indications for certain Lyme tests to support modified two-tier testing algorithms.
  • CDC describes interpreting Lyme antibody testing as a two-step process.

What this can tell you

  • Why two EIA-type results may appear on a report.
  • What to ask about the final interpretation.

What this cannot tell you

  • Whether one test name alone establishes a diagnosis.
  • Whether a website can validate a laboratory workflow.

A useful question for your clinician

Was a modified two-tier algorithm used, and what is the final interpretation of both tests together?
Sources (2)
  1. U.S. Food and Drug Administration. ‘FDA Clears New Indications for Existing Lyme Disease Tests That May Help Streamline Diagnoses.’ July 29, 2019. https://www.fda.gov/news-events/press-announcements/fda-clears-new-indications-existing-lyme-disease-tests-may-help-streamline-diagnoses. Open source ↗
  2. Centers for Disease Control and Prevention. ‘Testing and Diagnosis for Lyme Disease.’ https://www.cdc.gov/lyme/diagnosis-testing/index.html. Accessed July 24, 2026. Open source ↗