Feline Leukemia (FeLV)
Feline leukemia virus (FeLV) is a retrovirus spread readily through saliva and close contact that can cause cancer and immune suppression. FeLV antigen testing supports identification of infection, including asymptomatic carriers. Point-of-care quantitative testing provides an objective antigen result for retrovirus screening.
Fact Table
| Species | Feline |
|---|---|
| Biomarkers | Feline Leukemia Virus (FeLV) |
| Tests |
Clinical Context
Feline leukemia virus (FeLV) is a retrovirus spread readily through saliva and close contact that can cause cancer and immune suppression. FeLV antigen testing supports identification of infection, including asymptomatic carriers. Point-of-care quantitative testing provides an objective antigen result for retrovirus screening.
Interpretation should combine the quantitative result with the patient's signalment, history, clinical signs, vaccination or treatment history where relevant, and any other laboratory findings. A single value is rarely diagnostic on its own; serial measurements often provide more useful information.
Related Biomarkers
Related Test Kits
Related Articles
- FeLV and FIV in Cats: What a Positive Really Means FeLV and FIV are two retroviruses with two different tests. Here's why a kitten FIV positive is often false and what the results actually mean.
- Cat Infectious Disease Testing: What One Panel Can Catch A guide to feline infectious disease testing: FPV, FHV-1, FCV, FCoV, FeLV and FIV — when to test and how to interpret results.
Clinical literature cited in related articles
2026-09-12
MEDIUM
FAQ
What is the difference between FeLV and FIV?
Feline leukaemia virus (FeLV) and feline immunodeficiency virus (FIV) are both retroviruses but differ in transmission and disease. FeLV spreads readily through saliva and close contact and can cause cancer; FIV spreads mainly through bite wounds and causes immune suppression.
How are FeLV and FIV detected?
FeLV is typically detected by antigen testing (the p27 core antigen) in blood, while FIV is detected by antibody testing. Quantitative fluorescence assays provide objective results for both, supporting diagnosis and monitoring.
When should cats be tested for FeLV and FIV?
Testing is recommended for new cats entering a household, sick cats with unexplained illness, cats with bite wounds or outdoor access, and before vaccination. Retrovirus screening is a standard part of preventive feline care.