How to Recognize and Diagnose Feline Leukemia in Cats
Feline leukemia virus (FeLV) is one of the most significant and common infectious diseases affecting cats. Understanding its symptoms, risk factors, transmission, and diagnosis can help safeguard your pet's health.
What Is Feline Leukemia?
FeLV is a retrovirus that targets a cat’s immune system and blood cells, potentially resulting in severe illnesses such as cancer, anemia, and immunosuppression. While only infecting cats, it is highly contagious among them through close contact.
Risk Factors for FeLV
- Living with FeLV-positive or untested cats
- Outdoor access or free-roaming behavior
- Multi-cat households, shelters, or catteries
- Receiving blood transfusions from infected donors
- Exposure through mutual grooming, shared dishes, or bite wounds
Kittens and young adult cats are especially vulnerable due to underdeveloped immune defenses.
Methods of Transmission
FeLV spreads primarily through saliva during close contact. It can also be transmitted via:
- Shared food or water bowls
- Litter boxes
- Nursing from an infected mother
- Urine and feces (to a much lesser extent)
The virus does not survive long outside the body, so direct and prolonged exposure is usually required for transmission.
Types of FeLV Infections
There are three possible outcomes after exposure to FeLV:
- Abortive infection: The cat’s immune system eliminates the virus entirely. These cats are not contagious and show no symptoms.
- Regressive infection: The virus is contained within body compartments and is not present in the bloodstream. It can reactivate later under immune suppression.
- Progressive infection: The virus remains in the bloodstream. Cats become contagious and are more likely to develop diseases or die prematurely from the effects of FeLV.
Signs and Symptoms of FeLV
FeLV symptoms are variable and may take weeks to years to manifest. Watch for:
- Loss of appetite and weight loss
- Poor coat condition
- Pale or yellow gums
- Enlarged lymph nodes
- Persistent fever
- Lethargy
- Stomatitis and gingivitis
- Recurrent infections (e.g., urinary, respiratory)
- Diarrhea
- Eye problems
- Reproductive issues like abortion or infertility
- Anemia or cancer (especially lymphoma)
- Neurological symptoms or seizures
How FeLV Is Diagnosed
Veterinarians use multiple diagnostic tests:
- ELISA: Detects FeLV antigens in blood during early or active infection. Commonly used for screening.
- IFA: Confirms persistent infections by detecting the virus in white blood cells and platelets.
- PCR: Identifies FeLV DNA in a cat's genome, useful for ambiguous or regressive cases.
Since a single result may not provide conclusive information, retesting after several weeks is often recommended to determine infection stage.
What Happens After Diagnosis?
Although no cure currently exists for FeLV, supportive care and monitoring can significantly prolong quality of life. Treatment includes:
- Managing secondary infections with antibiotics
- Addressing anemia or cancer through blood transfusions or chemotherapy
- Providing immune-boosting drugs
- Ensuring excellent nutritional support and routine health checks
Preventing Feline Leukemia
- Keep cats indoors to prevent exposure
- Test all new or stray cats before introducing them to your household
- Avoid sharing food, water, or litter between FeLV-positive and healthy cats
- Neuter and spay cats to reduce aggressive interactions
- Vaccinate kittens and high-risk cats, but only after confirming they are FeLV-negative
Even vaccinated cats can contract FeLV if exposed, so routine testing and prevention remain essential.
Caring for a Cat With FeLV
Once diagnosed, a FeLV-positive cat should be:
- Kept indoors to limit exposure and reduce infection risk
- Monitored for weight changes, appetite, and behavior
- Regularly examined by a veterinarian
- Promptly treated for any signs of secondary illness
With attentive care, many FeLV-infected cats live comfortably for several years, though prognosis is more guarded for those with progressive infections.
Conclusion
Early diagnosis, vigilant care, and preventative strategies are key to managing feline leukemia. If your cat shows any concerning symptoms or is at risk, consult a veterinarian immediately for testing and guidance. Knowledge and proactive healthcare can make a significant difference in your cat’s quality of life.
