INTENDED USE:

A rapid, qualitative detection of influenza type A and type B antigens directly from nasal swab, nasal wash, and/or nasal aspirate specimens. The test is intended for use as an aid in the rapid diagnosis of acute influenza virus infection. The test is not intended to detect influenza C antigens.

SUMMARY AND EXPLANATION:

Influenza is a highly contagious, viral infection of the respiratory tract. The causative agents of the disease are immunologically diverse, single-strand RNA viruses known as influenza viruses. A,B,and C.  Type A viruses are the most prevalent and are associated with the most serious epidemics. Type B viruses produce a disease that is generally milder than that caused by type A. Type C viruses have never been associated with a large epidemic of human disease. Both type A and B viruses can circulate simultaneously, but usually one type is dominant during a given season.

PRINCIPLE:

The Quick Vue Influenza Test involves the extraction of influenza A and B. viral antigens. The patient specimen is placed in the Extraction reagent tube; during which time the virus particles in the specimen are disrupted, exposing internal viral nucleoproteins.

The Test Strip is placed in the extraction tube and the nucleoproteins in the specimen will react with the reagents in the Test Strip.

If the extracted specimen contains influenza antigens, a pink-to-red Test Line along with a blue procedural Control Line will appear. On the Test strip indicating a positive result. The Test Line for influenza A or B will develop at separate specified locations on the same Test Strip.  If influenza type A or B antigen are not present, or are present in a very low level, only a blue Control Line will appear.

MATERIAL NEEDED:

• Reagents:
  • Test Strip
  • Extraction Reagent Solution
  • Extraction tube
  • Sterile Swab
• Controls:
  • Positive Influenza type A Control Swab
  • Positive Influenza type B Control Swab
  • Negative Control Swab

SPECIMEN:

Nasal swab Sample

1. Use the swab supplied in the kit.
2. Insert the sterile swab into the nostril that presents the most secretion under visual inspection
3. Using gentle rotation, push the swab until resistance is met at the level of the turbinates, (less than one inch into the nostril)Rotate the swab a few times against the nasal wall.
4. Samples should be tested as soon as possible after collection.
5. If transport of the samples is required, the following Transport Media are recommended and have been tested and shown not to interfere with the performance of the test: Hank’s Balanced Salt Solution,  M5 Media, or saline. Alternatively, samples may be stored refrigerated (2–8°C), or at room temperature (15–30°C), in a clean, dry, closed container for up to eight hours prior to testing. Nasal wash specimens may also be stored frozen (-70°C or colder) for up to one month.

PROCEDURE:

1.	Dispense all of the Extraction Reagent Solution from the Reagent Tube. Gently swirl the Extraction Tube to dissolve its contents.
2.	Place the patient swab sample into the Extraction Tube. Roll the swab at least three times while pressing the head of the swab against the bottom and side of the Extraction Tube,
3	Leave the swab in the Extraction Tube for one (1) minute
4.	Roll the swab head against the inside of the Extraction tube as you remove it. Dispose of the used swab in the biohazard waste disposal.
5.	Place the Test Strip into the Extraction Tube with the arrows on the Test Strip pointing down. Do not handle or move the Test Strip until the test is complete and ready for reading.
6.	Read result at 10 minutes.    Some positive results may appear sooner.

INTERPRETATION:
Positive Result: At ten minutes, ANY shade of a pink-to-red Test Line forms, either above or below the blue control line, AND the appearance of a blue procedural Control Line indicates a positive result for the presence of influenza A and/or B viral antigen. Hold the test strip with the arrows pointed down. If the red line is above the Control Line, the test results are positive for type A. See image to the immediate right (A+). If the red line is below the Control Line, the test results are positive for type B. See image to the far right (B+). Negative Result: At ten minutes, the appearance of ONLY the blue procedural Control Line indicates the sample is negative for influenza A and B viral antigen. A negative result should be reported as a presumptive negative for the presence of influenza antigen. Invalid Result: If at ten minutes, the blue procedural Control Line does not appear, even if any shade of a pink-to-red Test Line appears, the result is considered invalid. If at ten minutes, the background color does not clear and it interferes with the reading of the test, the result is considered invalid. If the test is invalid, a new test should be performed with a new patient sample and a new Test Strip. If the blue procedural Control Line does not develop at 10 minutes, the test is considered invalid. If background color appears and interferes with the test result, the result is considered invalid.

QUALITY CONTROL:

• INTERNAL CONTROL:
  • The appearance of the blue Control Line demonstrates:
    • Sufficient capillary flow has occurred
    • The functional integrity of the Test Strips was maintained.
  • The clearing of the red background color verifies:
    • The test was performed correctly
    • Background color that interferes with the interpretation of the result is considered invalid test.
• EXTERNAL CONTROL:
  • Positive and negative controls tests should be performed at the opening of a new kit. 
  • Control tests are performed following the test procedure. 

STORAGE:

• Store the kit at room temperature. 59°-86° F (15°-30° C), avoid direct sun light. Do not freeze. Kit contents are stable until the expiration date printed on the box.

WARNINGS AND PRECAUTIONS:

• Test kit is for in vitro diagnostic use.
• Do not use kit contents beyond the expiration date on the box.
• Use appropriate precautions in the collection, handling, storage, and disposal of patient samples and kit contents. Discard used material in a proper biohazard or sharps container.
• The test strip must remain sealed in the protective foil pouch until use.
• The Extraction reagent contains a salt solution. If the solution contacts the skin or eye, flush with copious amounts of water.
• Although this test has been shown to detect cultured avian influenza viruses, including avian Influenza A subtype H5N1 virus, the performance characteristics of this test with specimens from humans infected with H5N1 or other avian influenza viruses are unknown.

PROCEDURAL NOTES:

• Whole blood, and several over-the-counter (OTC) products and common chemicals were evaluated and did not interfere with the QuickVue Influenza A+B test.

EXPECTED VALUES:

• Seasonal outbreaks of influenza occur worldwide in both the northern and southern hemispheres causing widespread illness each winter. The average attack rate of influenza is 26–33 cases per 100 people per year. The risk of hospitalization is roughly 1/300 of those infected among the very young and elderly. Approximately 36,000 deaths in the U.S. are attributed to influenza or its complications each year. Ninety percent (90%) of deaths occur in those 65 years of age and older. During each of three major epidemics occurring in 1957 and 1968, more than 40,000 people died of influenza in the U.S. alone.

• In the 1918 pandemic, an estimated 50 million deaths resulted worldwide. In the multicenter clinical study conducted by Quidel during an influenza season in North America, an illness prevalence of 24% for type A and 15% for type B influenza was observed.

LIMITATIONS:

• The contents of this kit are to be used for the qualitative detection of influenza A and B antigen from nasal swab, nasopharyngeal swab, nasal wash, and nasal aspirate specimens.
• Failure to follow the Test Procedure and Interpretations of Test Results may adversely affect test performance and/or invalidate the Test Result
• Test Results must be evaluated in conjunction with other clinical data available to the physician.
• A negative test result may occur if the level of antigen in a sample is below the detection limit of the test, or from improper sample collection. Negative test results are not intended to rule-out other non-influenza viral infections.

SENSITIVITY AND SPECIFICTY:

• Test inserts indicate that QuickVue Influenza A+B Nasopharyngeal Swab Results versus Culture Type A Sens =83% Spec =  89% Type B Sens 67%) Spec  98%

ASSISTANCE:

• Contact St. Peter’s Hospital Laboratory  Point-of-Care-Testing ext# 2319

• If you have any questions regarding the use of this product, please call Quidel’s Technical Support Number (800) 874.1517 (toll-free in the U.S.A.) or (858) 552.1100, Monday through Friday, between 7:00 a.m. and 5:00 p.m., Pacific Time, U.S.A.

REFERENCES: QuickVue influenza A+B insets. # 1063803 (02/06)  www.quidel.com

PLACED INTO SERVICE: September 17, 2005   Revised 5-22-06

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