What is FeLV?

FeLV is a contagious virus that weakens a cat’s immune system and can lead to:

Cancer (especially lymphoma)
Anemia, usually very severe
Repeating or chronic infections

FeLV is incurable, but supportive and close veterinary care can help infected cats live for months or even years with a good quality of life.

Stages of Infection

Not all FeLV-positive cats are condemned. Outcomes fall into three categories:

Abortive infection: The cat clears the virus and will test negative at some point in the future.
Regressive infection: The cat carries viral DNA but does not get sick. These cats are not infectious.
Progressive infection: The cat actively sheds the virus and is at risk of FeLV-related disease. These cats are infectious to others.

About two-thirds of exposed cats fall into the abortive or regressive category.

How FeLV is Transmitted

FeLV spreads through:

Saliva – grooming, shared bowls, bites (especially in unvaccinated cats)
Mother to kittens – in the womb or through milk
Blood transfusions – if the donor is infected

Cats that roam outside are at high risk, even if they only go out occasionally (the typical phrase we hear, just briefly in our garden…)

Symptoms to Watch For

Signs can vary depending on the cat and the stage of disease:

Lethargy
Fever
Anemia
Recurrent infections, very commonly dental conditions like gingivostomattis
Vomiting or diarrhea
Neurological changes
Lymphoma or enlarged lymph nodes
Swollen kidneys/spleen
Jaundice

Diagnosis

All cats with outdoor access but be checked for FELV
FeLV speed test
PCR test
Complete Blood Count (CBC) and biochemistry
Immunofluorescent Antibody Test (IFA)
Ultrasound / X-rays (to detect organ changes or tumors)

Treatment & Management

While there is no cure, treatment aims to:

Treat secondary infections
Symptomatic treatment
Support immune function

Virbagen Omega (omega interferon) may help reduce viral impact and boost immunity. While not a cure, it can slow progression.

Note: Panacea Vets regularly restocks this medication, despite it being unavailable in many places. It’s a pricey treatment that consists of 3 courses of injections.

Prevention

FeLV vaccine: Essential for all cats with any outdoor access, even if occasional
Keep FeLV-positive cats indoors to prevent transmission
Routine health checks and blood work, especially for outdoor or rescue cats

Final Notes

FeLV-positive cats, especially those who are indoor-only and receive regular care, can live happy, meaningful lives. Early detection and Prevention remain the most powerful tools.

For questions, testing, vaccination, or treatment support, contact us.