Rapid self-test for the detection of anti borrelia IgM antibodies in blood in case of tick bites. (Lyme disease)
Intended Purpose
TIK’ALERT® test is a manual qualitative immunochromatographic screening test for the detection of anti-borrelia IgM antibodies in finger prick whole blood sample. It can be used at home by lay users for self-testing for the detection of possible IgM antibodies to Borrelia bacteria further to recent tick bite. This screening test cannot detect the stage of the illness in case of positive results.
General Points
Ticks are insects living in undergrowth and forests of temperate climatic zones. Those insects can be infected by a bacterium (Borrelia) that can be then transmitted to humans after being bitten on the arm, the leg and any other part of the body not protected with clothes. Borrelia bacterium affects the nervous system and can lead to serious neurological disorders. European strains of Borrelia include B. afzelli, B. garinii, B. burgdoferi sensu stricto B. spielmanii, and B. bavariensis which are known pathogenic. Species B. valaisiana and B. lusitaniae are potentially pathogenic. That infection can also cause cutaneous lesions and arthritis. From 3 to 10 days, or even several weeks, after being bitten, an inflammation and redness (erythema) can appear in the bite region. The inflammation can be accompanied by feverishness. In case of infection, the immune system reacts by releasing specific antibodies directed against Borrelia bacterium. A particular category of antibodies (IgM: immunoglobulins M) which appears first can be detected between 2 and 6 weeks after being infected. Lyme disease develops in 3 stages: In phase I (2 to 4 weeks), The IgM antibodies appear only in 40 to 60 % of the cases. During the phase II (4 to 6 weeks later), the antibodies are detectable in 70 to 90 % of the cases. At last, during phase III, the antibodies are generally present and can be detected.
Test Procedure
Prepare everything properly before starting the testing procedure. Place the content of the box on a clean, dry and flat surface (e.g. table). Then perform the test as follows:
- Wash your hands thoroughly. Use soap and warm water. Dry your hand with clean towel.
- Prepare the test device and capillary pipette: Take them out from the protective pouch (tear at the notch) and place them in the reach of your hands (you will need them later). Discard the desiccant bag.
- Prepare the lancet. Hold the lancet without touching the trigger button. Unlock the cap twisting it off ¼ turn until you feel it separates from the lancet and then continue twisting it (2-3 rotations). Don’t pull just twist and discard the cap when finished. ①②
- Clean the end of the middle or ring finger with cotton damped with alcohol. Massage the chosen finger towards the tip for 10 to 15 seconds to enhance the blood flow.
- Prick the finger: put the lancet firmly against the side of the previously cleaned finger, and press the release trigger button.③ The lancet will automatically retract into the body of the device. Gently massage the finger to create a nice round blood droplet.④
- Collect the blood with the capillary pipette: Gently touch the blood droplet with the open end of the capillary pipette. It must be filled until the line indicated on the capillary pipette. Do not press the bulb, it fills by itself. Make another blood droplet if the line is not reached. As far as possible, avoid air bubbles. ⑤
- Put the blood collected with the pipette into the sample well of the device, by pressing on the pipette bulb. ⑥
- Wait 30-40 sec for the blood being totally absorbed into the sample well.
- Add the diluent: Unscrew the blue cap of the diluent dropper vial (leave the white cap tightly screwed) and add the diluent as follows: Hold the diluent dropper vial vertically and slowly add exactly 4 drops in the sample well of the device with an interval of 2-3 seconds between each drop. ⑦
- Read the result after 10 minutes. Do not interpret after 15 minutes.
Results Interpretation
The intensity and the colour of the lines do not have any importance for the interpretation of the test results.
Analyze
Result
Summary
Positive result
Negative result
Invalid result
Questions and answers
How does TIK’ALERT® work?
In presence of Borrelia bacterium transmitted by a tick, specific IgM antibodies are produced first by the immune system. The antibodies circulate in the blood and bind on the encountered bacteria. The Borrelia antigens coated on the TIK’ALERT® strip specifically detect those antibodies by producing a coloured line under the T mark of the cassette.
A control line capturing the reagent excess appears as a coloured line under the C mark of the cassette. In case both lines appear, the presence of Borrelia bacterium can be suspected.
When should the test be performed?
TIK’ALERT® test should be performed between 2 and 6 weeks after being bitten by a tick or as soon as a round inflammation (erythema) appears on a part of the body likely which was exposed to a tick bite. It corresponds to the phase 1 of the disease for which the TIK’ALERT® is well suitable and for which the test sensitivity is 53.8%. The presence of IgM antibodies, detected thanks to a positive result, indicates an infection that should be rapidly treated.
Contamination happens only in 1 to 2% of the cases, but the presence of IgM antibodies, detected thanks to a positive result, indicates an infection that should be rapidly treated.
Can the result be incorrect?
The results are accurate as long as the nstructions are carefully respected. Nevertheless, the result can be incorrect if TIK’ALERT® test gets wet before test performing or if the quantity of blood dispensed in the sample well is not correct. The plastic pipette provided in the box makes sure the collected blood volume is correct.
How to interpret the test if the colour and the intensity of the lines are different?
The colour and intensity of the lines have no importance for result interpretation. The lines should only be homogeneous and complete. The test should be considered as positive regardless of the colour intensity of the test line is (T) even weak.
What is the line that appears under the mark C (Control) for?
When this line appears, it only means that the test has been performed well.
If I read the result after 15 minutes, will the result be reliable?
No. The test should be read 10 minutes after adding the diluent. The result is reliable up to 15 minutes.
What do I have to do if the result is positive?
If the result is positive, it means that IgM antibodies directed against Borrelia bacterium are detectable in blood and that you must absolutely consult a doctor showing him the test result. Then, the doctor will order a treatment to follow in order to avoid complications arising after this infection. In case of past infection having occured several years before, a positive result can be obtained as the antibodies may be persisting in some persons. A positive result can also be obtained in patient having been efficiently cured with antibiotics.
What do I have to do if the result is negative?
If the result is negative, it means that no IgM antibodies directed against Borrelia bacterium are detectable in blood. Caution: Falsely negative results can be observed during phase I (antibodies appearing in 40 to 60% of the cases) or during phase II (antibodies rising in 70 to 90% of the cases) of the disease development. In case of negative result, it is strongly recommended to perform a new test 2 to 6 weeks later in order to check the increase of antibodies level. If you have been preventively treated by antibiotics, the antibodies are not detectable or cannot be detected. If the tick’s bite is too recent (less than 2 weeks), your organism has not had enough time to produce detectable antibodies. It is recommended to repeat the test with a new TIK’ALERT® 2 to 6 weeks after the presumed bite. However, if a rash, accompanied or not by feverishness, persists, it is recommended to consult your doctor.
What is the accuracy of TIK’ALERT®?
The TIK’ALERT® test is accurate and has been used for more than 10 years by professionals in the field (hospitals, laboratories…). Evaluation reports show an overall agreement of 89.19% CI95% [81.14 – 94.46**] with reference methods. Despite the reliability of the test, falsely positive or false negative results are possible. This is especially true for patients being sero positive for cytomegalo-viruses (CMV), Epstein Barr virus (EBV), herpes simplex virus (HSV), syphilis, leptospirosis, mononucleosis or autoimmune disorders which may show false positive results when using the TIK’ALERT® test.
** CI 95%: 95% Confidence Interval
Information on Borrelia infections and related disease
- La borréliose de Lyme. Haut Conseil Santé Publique. 28 mars 2014.
- Web information: Borreliosis. Wikipedia.