At a Glance
Why Get Tested?
When to Get Tested?
If you show symptoms of Lyme disease, especially if they appear some weeks after a painless bite from a small tick or you have recently been in woodland or long grass
A blood sample taken from a vein in the arm
Test Preparation Needed?
The Test Sample
What is being tested?
Your blood is being tested for antibodies to the Lyme disease bacterium. Their presence means you have been infected with the Lyme disease spiral bacterium (spirochaete) known as Borrelia burgdorferi by a bite from an infected tick.
People bitten by an infected tick which is not removed within a day or so may develop Lyme disease. An expanding rash called erythema migrans appears at the site of the bite within 3 to 30 days in a large proportion of those infected. The rash spreads and often develops a “bulls-eye” appearance. Many also develop flu-like symptoms with aching joints and muscles. The disease can later affect the nervous system, joints and other body systems.
It takes the body two to three weeks to produce detectable levels of B. burgdorferi antibodies. Immunoglobulin M (IgM) antibodies are produced first, increase to maximum concentrations at about six weeks and then begin to decline. Immunoglobulin G (IgG) antibodies are detectable several weeks after exposure, increase to maximum levels at about four to six months, and may remain at high levels for many years.
How is the sample collected for testing?
A blood sample is taken by needle from a vein in the arm. Sometimes, if indicated by your symptoms, a cerebrospinal fluid (CSF) sample or a sample of joint fluid (synovial fluid) is taken. Very occasionally a skin biopsy is taken from a rash.
NOTE: If undergoing medical tests makes you or someone you care for anxious, embarrassed, or even difficult to manage, you might consider reading one or more of the following articles: Coping with Test Pain, Discomfort, and Anxiety, Tips on Blood Testing, Tips to Help Children through Their Medical Tests, and Tips to Help the Elderly through Their Medical Tests.
Another article, Follow That Sample, provides a glimpse at the collection and processing of a blood sample and throat culture.
Is any test preparation needed to ensure the quality of the sample?
No test preparation is needed.
Ask a Laboratory Scientist
NOTE: This article is based on research that utilizes the sources cited here as well as the collective experience of the Lab Tests Online Editorial Review Board. This article is periodically reviewed by the Editorial Board and may be updated as a result of the review. Any new sources cited will be added to the list and distinguished from the original sources used.