1. INTENDED USE

The CHW Ag Rapid Test is a fluorescence-based immunoassay designed for the qualitative detection of Dirofilaria immitis antigen in canine whole blood, serum, or plasma. This test provides veterinarians with:

• Early screening for heartworm infection (even in prepatent period)
• Confirmation of suspected cases (e.g., dogs with clinical signs like coughing or exercise intolerance)
• Monitoring treatment efficacy post-adulticide therapy

Note: For veterinary point-of-care use. Positive results should be confirmed with additional diagnostic methods.

2. TEST PRINCIPLE

The test utilizes a sandwich fluorescence immunoassay format:

1. Capture Phase:
   • Anti-heartworm monoclonal antibodies are immobilized on the test strip
   • CHW Ag in sample binds to these antibodies
2. Detection Phase:
   • Fluorescent nanoparticle-conjugated antibodies form complexes with captured antigen
   • Unbound conjugates are washed away
3. Signal Generation:
   • A handheld reader quantifies fluorescence intensity at 650nm
   • Results are displayed as:
     Positive: >15 U/mL (detects ≥0.1 ng/mL antigen)
     Negative: <10 U/mL

Key Features:
✔ 98.7% sensitivity (vs. 86% for traditional ELISA)
✔ 100°C stable conjugate particles for tropical climates
✔ 15μL minimum sample volume (fingerstick whole blood compatible)

Storage: 2-30°C (avoid freeze-thaw cycles for reagents)
Run Time: 9 minutes (including 3-minute incubation)