INTENDED USE
The Strep A Rapid Test Cassette is a rapid immunoassay designed for the qualitative detection of Group A Streptococcal antigen from throat swab specimens.
SUMMARY
Streptococcus pyogenes is a non-motile, gram-positive bacterium that contains the Lancefield Group A antigen, which can cause serious infections such as pharyngitis, impetigo, endocarditis, and meningitis. Left untreated, these infections can lead to complications such as rheumatic fever and peritonsillar abscess. Traditional methods of identifying Group A Streptococci involve time-consuming cultures, but the Strep A Rapid Test provides results in 15 minutes, utilizing specific antibodies to detect the presence of Strep A antigen in throat swab samples.
PRINCIPLE
The Strep A Rapid Test is a membrane-based immunoassay that detects Group A Streptococcal antigen. Anti-Strep A antibodies are immobilized on the test line region. Once a sample is placed, it reacts with the antibody-coated particles on the pad, migrating along the strip. A colored line in the test line region indicates a positive result. A control line appears to confirm sufficient specimen volume and proper test function.
WARNINGS AND PRECAUTIONS
- For professional in vitro diagnostic use only.
- Do not use after the expiration date.
- Handle all specimens as potentially infectious.
- Wear protective clothing and follow biosafety guidelines.
- Humidity and temperature may affect the results.
COMPOSITION
The test contains a membrane strip coated with anti-Strep A antibodies and a control line of goat anti-mouse IgG antibody. The dye pad contains colloidal gold conjugated with anti-Strep A antibodies.
MATERIALS PROVIDED
- Test cassette
- Extraction reagents A and B
- Sterile swab
- Extraction tube and dropper tip
- Package insert
MATERIALS REQUIRED BUT NOT PROVIDED
- Specimen collection container
STORAGE AND STABILITY
Store the kit in a sealed pouch at 4-30°C. Use the test within one hour of opening the pouch. Avoid prolonged exposure to high temperatures or humidity. The expiration date is printed on the labelling.
SPECIMEN COLLECTION
Collect throat swabs using standard clinical methods. Avoid using swabs with cotton, calcium alginate tips, wooden shafts, or transport media with agar. Process samples immediately or refrigerate them at 2-8°C for up to 5 days if testing is delayed.
TEST PROCEDURE
- Allow the test device and specimens to reach room temperature (15-30°C) before testing.
- Remove the test cassette from the pouch.
- Add 5 drops of Reagent A and 4 drops of Reagent B into the extraction tube. Mix.
- Insert the swab into the tube, swirl 15 times, and leave for 1 minute. Remove the swab while squeezing the tube.
- Add 3 drops of the extracted solution to the specimen well (S) of the test cassette.
- Wait 5 minutes and read the result. Do not interpret after 10 minutes.
INTERPRETATION OF RESULTS
- Positive: Two lines (test and control) indicate the presence of Strep A antigen.
- Negative: Only the control line appears, indicating no antigen detected.
- Invalid: If no control line appears, the test is invalid and should be repeated.
QUALITY CONTROL
The appearance of the control line confirms proper procedure and sufficient specimen volume. It is recommended to run positive and negative controls regularly to ensure test performance.
LIMITATIONS
- For in vitro diagnostic use only.
- The test detects the presence of Strep A antigen, not the quantity.
- Negative results do not rule out infection; further testing may be necessary.
PERFORMANCE CHARACTERISTICS
The Strep A Rapid Test demonstrated a sensitivity of 98.06% and a specificity of 99.40% compared to commercial rapid tests and ELISA. No cross-reactivity with other microorganisms or interference from common substances was observed.
For professional and in vitro diagnostic use only