Feline leukemia virus
species of virus

Feline leukemia virus (FeLV) is a retrovirus that infects cats. FeLV can be transmitted by infected cats via the transfer of saliva or nasal secretions. If the animal's immune system fails to neutralize the virus, it may become severely weakened by it, potentially leading to lethal disease. Because FeLV is cat-to-cat contagious, FeLV+ cats should only live with other FeLV+ cats.
FeLV is categorized into four subgroups, A, B, C and T. An infected cat has a combination of FeLV-A and one or more of the other subgroups. Symptoms, prognosis and treatment are all affected by subgroup.
FeLV+ cats often have a shortened lifespan, but can still live relatively normal, healthy lives.
Signs and symptoms
The signs and symptoms of infection with feline leukemia virus are quite varied and include loss of appetite, poor coat condition, anisocoria (uneven pupils), infections of the skin, bladder, and respiratory tract, oral disease, seizures, lymphadenopathy (swollen lymph nodes), skin lesions, fatigue, fever, weight loss, stomatitis, gingivitis, litter box avoidance, pancytopenia, recurring bacterial and viral illnesses, anemia, diarrhea and jaundice.
Asymptomatic carriers are still immune suppressed, with potential delayed and decreased antibody responses.
Progression
The disease has a wide range of effects.
This brief starts where responsible research should: with the source description of “Feline leukemia virus” as species of virus. Everything that follows is an evidence route, not borrowed authority.
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This entry incorporates text from “Feline leukemia virus” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.