Strep B Ag
Rapid Test
A rapid test for the qualitative detection of Strep B antigen in
specimens taken from vaginal or rectal swabs of pregnant women, or
general swabs from newborn.
Intended Use
The Strep B Rapid Test Cassette (Swab) is a rapid visual immunoassay for the qualitative, presumptive detection of Group B Streptococcus (GBS) antigens in specimens taken from vaginal or rectal swabs of pregnant women, or general swabs from newborn. This kit is intended for use as an aid in the diagnosis of Strep B infection.
How Does it Work
The Strep B Rapid Test Cassette (Swab) detects Group B Streptococcus antigens through visual interpretation of color development on the internal strip. Anti-Strep B antibodies are immobilized on the test region of the membrane. During testing, the specimen reacts with polyclonal anti-Strep B antibodies conjugated to colored particles and pre- coated onto the sample pad of the test. The mixture then migrates through the membrane by capillary action, and interacts with reagents on the membrane. If there is sufficient Strep B antigen in the specimen, a colored band will form at the test region of the membrane. The presence of this colored band indicates a positive result, while its absence indicates a negative result. The appearance of a colored band at the control region serves as a procedural control, indicating that proper volume of specimen has been added and membrane wicking has occurred.
Interpreting the results
Note: It is suggested not to use the extraction reagents, beyond 30 days after opening the vial.
There will be no line in test region. Sometimes, you can see the position of the test line, but no color.
Positive: In addition to a pink colored control line ,for hemoglobin
positive, a lower test line near to sample well will appear, for transferrin positive, a upper test line near to control line will appear.
Invalid: A total absence of color in both regions is an indication of procedure error and/or that the test reagent has deteriorated. The test should be repeated using a new strip.
Relative Sensitivity: 95.2% (95%CI:*89.6%-98.2%)
Relative Specificity: 97.8% (95%CI:*95.8%-99.0%)
Overall accuracy: 97.2% (95%CI:*95.3%-98.4%)