Strep A Rapid Test

Product information

The Strep A Rapid Test a lateral flow, qualitative immunochromatographic rapid test for the detection of Streptococcus Group A antigen from throat swabs specimens.

Advantages of Strep A test

• Easy to perform
• No complex sample collection needed
• Accurate test result

General information

Among the beta-hemolytic streptococci causing infections in humans, the A, B, C and G groups figure most prominently (5).

Group A streptococci continue to be a focus of interest not only because of their causal role in acute streptococcal pharyngitis and other pyogenic infections but also because of their association with poststreptococcal sequelae, specifically acute rheumatic fever and acute glomerulonephritis (1, 2).

In order to properly treat the disease using antibiotic therapy, it is important to use an accurate diagnostic method to identify the pathologic agent.

For the screening of group A streptococcal infection several methods are currently used including susceptibility of the organism to a bacitracin disc placed on a sheep blood agar plate, latex agglutination and enzyme immunoassay (3, 4).

The Strep A test is a rapid qualitative assay for the detection of Streptococcus Group A antigen from throat swabs specimens.  The method employs a unique combination of monoclonal-dye conjugate and polyclonal solid phase antibodies to selectively identify Streptococcus A with a high degree of sensitivity.

As the test samples flows through the absorbent device, the labelled antibody-dye conjugate binds to the Strep-A antigen forming an antibody antigen complex. This complex binds to the anti-Strep-A antibody in the test zone (T) producing a pink-rose color band. In the absence of Strep-A, there is no line in the test zone (T). The reaction mixture continues flowing through the absorbent device. Unbound conjugate binds to the reagents in the control zone (C) producing a pink-rose color band, demonstrating that the reagents are functioning correctly.

Test procedure

1. Remove the test device from the pouch.
2. Place the specimen swab in a plastic tube (12 x 55 mm or comparable). Add 6 drops of extraction reagent 1 and 6 drops of extraction reagent 2. Twirl swab to mix the extraction reagents thoroughly. Incubate at room temperature for 3 minutes.
3. At the end of incubation time, squeeze the swab firmly against the side of the tube in order to remove as much as possible liquid from the swab. Discard the swab.
4. Add exactly 3 full drops of the extract solution (80 μL) into the sample well (▷) on reaction device using the plastic pipette.
5. Read results of the test at 5 minutes after addition of sample on the device.
6. Do not interpret after 10 minutes.

Interpretation of the results

Negative result: Only 1 colored band appears in the control zone (C). No band in the Test zone (T).

Positive result: In addition to the control band (C), a clearly distinguishable band also appears in the test zone (T), indicating a positive result.

Invalid result: If there is no distinct color band visible in the control zone (C) the test is inconclusive. It is recommended that in this case the test be repeated or a fresh specimen can be obtained and tested later.