1. What specimens are acceptable for this test?
Nasopharyngeal (NP) washes, NP aspirates, NP swabs and tracheal aspirates.
2. Can a frozen sample be run on this test?
Acceptable specimens are be fresh, refrigerated (2-8ºC for 48 hours) or frozen (at -20ºC) for up to 7 days.
3. My specimen is very mucoid. What can be done to the specimen so that it can be tested?
The specimen may be diluted 1:4 with 0.9 % saline, mixed well (or briefly sonicated) and retested.
4. Does the device need to be read at exactly 5 minutes after addition of reagent 5?
No. Adding Stop solution (reagent 6) will extend the read time period to a maximum of 12 hours.
5. Can a negative test device be used to test the positive control?
No, the test device may be used to run one test only.
6. At what temperature should the kit be stored?
The kit should be stored refrigerated (2- 8ºC) or at room temperature (15-30ºC).
7. Can I vortex the control reagents to mix them?
Yes, gently.
8. Can I use transport medium other than what is stated in the package insert?
An alternate transport medium must be validated by the user.
9. Is sample volume critical?
Sample size varies dependant upon sample type (refer to package insert). Sample volumes other than the recommended size may adversely affect results.
10. How critical is the timing in the incubation steps?
The first incubation step, following the addition of detector Reagent 2 is critical. A full 2 minute incubation should take place prior to adding Reagent 3. During this time, the detector is binding with any RSV antigen that is present. The final incubation time after the addition of the reagents (5 minutes) is equally important. If a positive reaction is present, the triangle will continue to deepen in color over time. Remember that an enzymatic reaction is taking place and to stop it, one must add Reagent 6 (Stop Reagent).
11. After extracting a specimen, I noticed that it appears pink/red. Can I use the sample?
Do NOT use the sample. When blood is present, extraction Reagent A will cause the release of hemoglobin, thus turning the sample pink or red. Hemoglobin competes with RSV antigen for sites on the membrane. This could cause a visible pink triangle, which could be incorrectly interpreted as a positive result. According to the package insert, excessively bloody samples have been found to yield either uninterpretable or false-positive results.
12. After running a test device, I can see the control dot and an outline of a triangle. Would this be considered positive?
No. This is an invalid test. If the flow controller is pressed hard or turned while pressing, it will leave a groove in the membrane. When the test is developing, the color may collect in the grooves. A positive result will have purple color throughout the entire triangle and the control dot.
13. Can I use centrifuged samples for the test?
This is not recommended. It may adversely affect the sensitivity of the test.
