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What is a false-positive tick-borne disease test?

A false positive is a reactive result in someone without the infection; background antibodies, cross-reactions and testing people with very low prior likelihood can reduce the result's predictive value.

Reviewed by VuxLore® Knowledge Team For Everyone

Short answer

A false positive is a reactive result in someone without the infection; background antibodies, cross-reactions and testing people with very low prior likelihood can reduce the result's predictive value.

At a glance

A false positive is a reactive result in someone without the infection; background antibodies, cross-reactions and testing people with very low prior likelihood can reduce the result's predictive value. Test choice and interpretation depend on timing, symptoms, geography and validated laboratory pathways. A result should never be separated from its clinical context.

Key takeaways

• A false positive is a reactive result in someone without the infection; background antibodies, cross-reactions and testing people with very low prior likelihood can reduce the result's predictive value.

• Test choice and interpretation depend on timing, symptoms, geography and validated laboratory pathways. A result should never be separated from its clinical context.

• This material is educational and cannot diagnose, exclude or treat illness. Use NHS 111, a GP, emergency services or the corresponding local service according to symptom severity.

Direct answer

A false positive is a reactive result in someone without the infection; background antibodies, cross-reactions and testing people with very low prior likelihood can reduce the result's predictive value.

Why context matters

Test choice and interpretation depend on timing, symptoms, geography and validated laboratory pathways. A result should never be separated from its clinical context.

What to do next

This material is educational and cannot diagnose, exclude or treat illness. Use NHS 111, a GP, emergency services or the corresponding local service according to symptom severity.

Sources and further reading

National Institute for Health and Care Excellence: Lyme disease: diagnosis and management (NG95)

US Centers for Disease Control and Prevention: Testing and Diagnosis for Lyme disease

Royal College of General Practitioners: Lyme Disease Toolkit