Blood test
Lyme disease testing
Lyme disease testing: what it measures, why a doctor orders it, how to prepare, and what a high or low result can mean - with private and NHS access routes in the UK.
Key facts
At a glance
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What it measures: antibodies to Borrelia, the tick-borne bacterium that causes Lyme disease, using a two-step laboratory pathway.
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Why it is ordered: when a tick exposure is followed by flu-like illness, joint pain or neurological symptoms - though the classic bullseye rash is treated on sight without any test.
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No fasting or special preparation is needed for this test on its own.
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Reference ranges: antibodies take several weeks to appear, so testing in the first weeks after a bite can be falsely negative and is often repeated. Every laboratory publishes its own interval, so the range printed on your report is the one that applies to you.
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A raised result or positive screening result is confirmed with a second, more specific immunoblot before the diagnosis is made. A low result or negative result late in an illness makes Lyme disease unlikely, while an early negative may simply be too soon.
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Results typically take a few days to two weeks, because the sample is analysed in batches at a specialist laboratory.
The full picture
What this test tells you, and how to get it
The Lyme disease blood test measures antibodies to Borrelia, the tick-borne bacterium that causes Lyme disease, using a two-step laboratory pathway. Doctors most often request it when a tick exposure is followed by flu-like illness, joint pain or neurological symptoms - though the classic bullseye rash is treated on sight without any test. No fasting or special preparation is needed for this test on its own. Antibodies take several weeks to appear, so testing in the first weeks after a bite can be falsely negative and is often repeated, and reference intervals genuinely differ between laboratories, so no single number should be treated as a universal cut-off - your result is always read against the range printed on your own report. Broadly, a raised result or positive screening result is confirmed with a second, more specific immunoblot before the diagnosis is made, while a low result or negative result late in an illness makes Lyme disease unlikely, while an early negative may simply be too soon, and either finding is interpreted alongside your symptoms, medication and other results rather than in isolation. Results typically take a few days to two weeks, because the sample is analysed in batches at a specialist laboratory.
In the UK there are two routes to this test. Your NHS GP can arrange it free of charge when it is clinically indicated, though getting the appointment, the blood draw and the follow-up discussion can add days to weeks depending on local demand. Privately, the Lyme disease blood test can usually be booked within days - through a private GP, a walk-in phlebotomy clinic or a self-request home-testing service - with NHS confirmation running through reference laboratories. A private result still deserves a clinician's interpretation: an isolated number without context is where most confusion about blood tests begins.
A quiet reminder
This guide is for information, not medical advice.
Your own clinician knows your history and can tell you which parts apply to you. Reference ranges vary between laboratories - always read your result against the interval printed on your own report. Next review of this page: 2027-09-27.
Frequently asked
Common questions about Lyme disease testing.
Quick, plain-English answers to what people ask us most.
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What does Lyme disease testing check for?
It looks for your body's antibody response to the bacteria that cause Lyme disease, typically transmitted through tick bites. Testing usually involves an initial screening test followed by a confirmatory test if the first is positive or unclear.
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Why would a doctor order Lyme disease testing?
It's typically requested if you've had a tick bite, especially with a spreading rash, or ongoing symptoms like fatigue, joint pain, or flu-like illness following possible tick exposure, particularly in areas where ticks are common.
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Do I need to prepare for the test?
No special preparation is needed, but timing matters: antibody tests can be negative in the first few weeks after a bite before your immune system responds, so your doctor may advise on the best time to test or repeat testing later.
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What happens during the test?
It's a simple blood draw from the arm, sent for antibody analysis, sometimes with a follow-up confirmatory test on the same or a fresh sample if needed.
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Does it hurt or carry risks?
There's only the brief discomfort of the needle, as with any blood test, and no significant risks involved.
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How long do results take?
Initial screening results are often available within a few days, though confirmatory testing can take a little longer.
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What do abnormal results mean, and what happens next?
A positive screening test is usually followed by a confirmatory test before treatment decisions are made, since false positives can occur. A confirmed positive result, especially with typical symptoms, usually leads to a course of antibiotics, most effective when started early. A negative result soon after a bite doesn't fully rule out infection, so your doctor may advise retesting or treating based on symptoms alone if a tick bite and rash were clearly seen.
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Is this test available on the NHS, and how much does private testing cost?
Lyme disease testing is available through the NHS, usually via a GP, though turnaround for confirmatory tests can take time. Private testing is typically available within days, with results reviewed by a doctor. Cost varies by provider.
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Is Lyme disease testing accurate and reliable?
The standard two-step testing approach is well validated, but antibody tests can be negative very early after infection and results always need interpreting alongside your symptoms and exposure history.
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How do I book this test privately, and how quickly can I be seen?
You can book privately online, often with results within a week, and have a doctor advise on treatment promptly if the result is positive, since early antibiotic treatment tends to work best.