Understanding Feline Leukemia: Signs, Symptoms, and Management
Feline leukemia virus (FeLV) is a serious and contagious viral infection that affects cats worldwide. It weakens a cat’s immune system, increases their risk of infections, causes cancer such as lymphoma and leukemia, and can lead to blood disorders like anemia. Recognizing the signs of FeLV is crucial for pet owners in managing the disease and providing proper care for their feline companions.
What Is Feline Leukemia?
FeLV is a retrovirus that primarily affects domestic cats. It spreads through saliva, blood, urine, feces, nasal secretions, and the milk of infected cats, with the most common transmission routes including:
- Mutual grooming and bite wounds
- Sharing food, water bowls, or litter boxes
- Mother-to-kitten transmission, either before birth or through nursing
The virus does not survive long outside the body, typically less than a few hours, which reduces the risk in indoor environments.
Behavioral and Physical Signs
Cats with feline leukemia exhibit a range of symptoms. Not all cats display signs immediately—they may appear healthy for weeks, months, or even years before clinical signs manifest. However, as the disease progresses, some common symptoms include:
- Loss of appetite and significant weight loss
- Lethargy and decreased activity
- Pale gums and mucous membranes, indicating anemia
- Enlarged lymph nodes
- Persistent fevers
- Unkempt or poor-quality coat
- Mouth ulcers or gum inflammation (gingivitis)
- Diarrhea and vomiting
- Chronic infections of bladder, skin, or respiratory tract
- Neurological issues such as seizures
- Eye disorders and reproductive issues in females
Stages of Infection
FeLV progresses in several stages:
- Primary Viremia: The virus enters the bloodstream. If the cat’s immune system is strong, it may eliminate the virus at this stage.
- Secondary Viremia: The virus infects bone marrow and tissues, leading to persistent infection and the ability to transmit the virus to others.
- Abortive Infection: In rare cases, cats completely clear the virus.
- Regressive Infection: Virus incorporates into the cat’s genetic material and remains dormant. These cats are not infectious and can live healthy lives for years.
Diagnosis
FeLV is commonly diagnosed using the ELISA test, which detects viral proteins in the blood. If the result is positive, further testing through IFA or PCR is recommended to confirm the presence of a persistent infection.
Because some cats can eliminate the virus or exhibit false positives, retesting after a few weeks is often necessary.
Treatment and Management
There is no cure for feline leukemia. Treatment focuses on managing symptoms, improving quality of life, and preventing secondary infections. Key supportive care measures include:
- Regular veterinary check-ups and preventive care
- Antibiotics or antifungals to manage recurring infections
- Nutritional support and minimizing stress
- Blood transfusions or medications for anemia
- Chemotherapy for cancer, although it has a guarded prognosis
Living With a FeLV-Positive Cat
With attentive care, FeLV-positive cats can live comfortable lives. To reduce the risk to other cats and themselves, they should:
- Be kept indoors to avoid further exposure
- Not share food, water bowls, or litter boxes with uninfected cats
- Receive early veterinary intervention for illness
Most persistently infected cats live up to three years after diagnosis, though some live much longer, especially with early diagnosis and good care.
Prevention
Preventing feline leukemia centers around minimizing exposure and maintaining preventive health practices:
- Vaccinate at-risk cats, especially kittens and those in multi-cat households
- Test cats for FeLV before vaccination or introducing new cats to the household
- Keep cats indoors or supervise their outdoor activity
It’s important to note that the vaccine is not 100% effective, but it greatly reduces the risk of infection. FeLV-positive cats should not be vaccinated, as the vaccine can overwhelm already compromised immune systems.
Is FeLV Contagious to Humans?
FeLV is species-specific and cannot infect humans, dogs, or animals other than felines. However, it can pose a risk to wild feline populations and should be managed to prevent spread.
Conclusion
Early recognition, regular veterinary care, and responsible management are critical in helping cats with FeLV lead healthy, fulfilling lives. Owners play an essential role in monitoring for symptoms, preventing transmission, and ensuring that their pets receive all necessary support and love.





