Special Precautions/Comments:

N.B. Please give relevant clinical details including the dates of onset and of tick contact.

Method: Enzyme immunoassay (EIA) for the determination of Borrelia burgdorferi IgG and IgM antibody levels. Positive EIA blood samples will be confirmed using immunoblot for the identification of Borrelia burgdorferi IgG and IgM antibodies using directed Borrelia antigens. Calibration: – EQA scheme: – IQC: –

Interpretation: Results will be reported as POSITIVE or Negative.

A negative EIA result does not rule out recent infection. If recent infection is suspected, consider sending follow up serology in 4-6 weeks’ time.

A positive EIA but negative immunoblot is most likely a non-specific result. However, this does not rule out early infection.

Patients with erythema migrans should always be treated on clinical suspicion.

For further information contact UKHSA Porton Down, Rare and imported pathogens laboratory (RIPL).

Additional Information:

Background information: Lyme disease is caused by a bacterial infection spread by infected ticks. Tick bites often go unnoticed as they are not always painful. High risk areas in the UK include grassy and wooded areas in southern and northern England and the Scottish Highlands.

The formation of a rash (erythema migrans) is often an early symptom of Lyme disease, this may be followed by a flu-like illness. Typically a rash will appear 1-4 weeks after a tick bite, although this may extend to 3 months post-bite. Please note that erythema migrans is a clinical diagnosis and does not require confirmation by laboratory testing.

Please provide clinical details to allow the interpretation of serological results. These are needed for interpretation because borrelia-specific antibodies may persist for several years in patients who have had Lyme disease in the past, long after the bacteria have been cleared from the body. Therefore, detection of borrelia specific antibodies in someone with no evidence of current clinical symptoms or recent tick exposure argues against active Lyme disease infection. After successful treatment of Lyme disease antibody concentrations may slowly fall over time.