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Accurate. Affordable. Simple.


The NEW WITNESS® FeLV-FIV (Feline Leukemia Virus Antigen – Feline Immunodeficiency Virus Antibody) Test Kit is an accurate, affordable and simple in-clinic test that detects the presence of feline leukemia virus (FeLV) antigen and feline immunodeficiency virus (FIV) antibodies.

  • ACCURATE: Excellent sensitivity* and specificity** as demonstrated in studies of clinical samples1,2

– FeLV: 92.9% sensitivity and 96.5% specificity 
– FIV: 93.8% sensitivity and 93.4% specificity

  • AFFORDABLE: Cost-effective alternative to other FeLV-FIV diagnostic tests
  • SIMPLE: Easy to use and store

– Requires no snapping; results in approximately ten minutes 
– One drop of sample needed for each result 
– No refrigeration necessary; twelve-month shelf life

  • Backed by Zoetis service and support


FeLV Results 1

1. Data on file, Study Report No. D880Z-US-14-013, Zoetis Inc.
2. Data on file, Study Report No. D880Z-US-14-014, Zoetis Inc.
* Sensitivity represents the ability to correctly identify positive samples.
** Specificity represents the ability to correctly identify negative samples.
 Tests: WITNESS® FeLV-FIV Test Kit, Zoetis Inc., Madison, NJ; IFA, performed at Antech Diagnostics, Irvine, CA; ViraCHEK®/FeLV ELISA, Zoetis Inc., Madison, NJ.
†† All were clinical plasma or serum samples from uninfected or naturally infected cats, sourced from:
      • Zoetis field study (n=75)
      • Antech Diagnostics (n=95)
      • Zoetis laboratory study (n=12)
††† All were clinical plasma or serum samples from uninfected or naturally infected cats, sourced from:
      • Cornell University (n=218)
      • Purdue University (n=14)
      • Antech Diagnostics (n=33)

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  • No Refrigeration
    WITNESS FeLV-FIV has a twelve-month shelf life at room temperature (versus only 90 days for a leading competitor’s test, which must be refrigerated). 

    No Snapping
    RIM™ (Rapid Immuno Migration) technology allows for a simpler process, compared to the ELISA method. So, unlike with other point-of-care tests, you don’t lose time waiting to snap. Plus, you only need one drop of sample (plasma, serum or anticoagulated whole blood) per result. 

    Rapid Results
    With accurate results in approximately ten minutes, you can give your clients the immediate test results they want.

    Easy to Interpret
    You get simple-to-understand results, with no complex interpretation needed. One result window for FeLV and FIV. For each test:

    • One line on the right = negative
    • Two lines = positive

    Backed by Zoetis Service and Support
    Same level of customer support you’re accustomed to receiving

    Watch the MOA video here

  • Sample Information

    One drop (0.05 mL) should be used. An appropriate sample can be any one of the following:

    • Plasma 
    • Serum 
    • Anticoagulated whole blood (blood that has been collected in an EDTA [purple top] or heparin [green top] tube)

    Instructions for Use

    1. Open the foil pouch and place the test kit on a flat horizontal surface for the duration of the test. 
    2. Using the supplied pipette, transfer one drop of sample (0.05 mL) onto window 1 of each sample well (FeLV and FIV) and allow for the sample to be completely absorbed. 
    3. Add two drops of buffer to each sample well (window 1). 
    4. Wait ten minutes for sample and buffer to migrate across the test kit into windows 2 and 3. 
    5. Read test results. When a control line appears in both rows of window 3, the test was performed correctly. Additional lines in either the FeLV or the FIV window indicate a positive result, respectively, while the absence of a second line in either window indicates a negative result for that specific disease.

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    How to Use the WITNESS FeLV-FIV Test Kit

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    Easy-to-Interpret Results

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    A couple of simple tips to ensure accurate results

    1. Check the expiration date on the side of the test carton. The test expires twelve months from the date of manufacture. 
    2. Perform the test within ten minutes after removal from the foil pouch. 
    3. Obtain the appropriate sample --plasma, serum or anticoagulated  whole blood. 
    4. Avoid touching or damaging the membrane of windows #1, #2 and #3. 
    5. Place the device on a flat, horizontal surface while performing the test. 
    6. Use a separate pipette for each sample. 
    7. Hold pipette and buffer bottle vertically when dispensing.

  • WITNESS FeLV-FIV detects the presence of feline leukemia virus (FeLV) antigen and feline immunodeficiency virus (FIV) antibodies. 

    • The WITNESS format is referred to as Rapid Immuno Migration (RIM™). This technology is also sometimes referred to as lateral flow or rapid immunochromatography.
    • WITNESS tests perform well without refrigeration using sensitized collidal gold particles. After the sample and buffer are added to the sample pad (window 1), the gold particles form a complex with either FeLV antigen or FIV antibodies present in the sample. The formed complexes continue to migrate laterally along their respective membranes. 
    • In a positive sample, the complexes are captured on a sensitized line where their accumulation causes formation of a clearly visible pink to purple line. Sensitized colloidal gold particles continue to flow across the membrane and are bound at the control line, where a visible pink- to purple-colored line certifies that the test has worked properly.

    A test result should always be interpreted in the context of all available clinical information and history for the cat.

All trademarks are the property of Zoetis Inc., its affiliates and/or its licensors. All other trademarks are the property of their respective owners. ©Zoetis Inc. All rights reserved. December 2014. WIT-00033


WITNESS® FeLV-FIV Mechanism of Action

Educational Information

VETgirl demonstrates the