Signs and Symptoms of FeLV

During the first few weeks after the initial infection, cats may have the following symptoms:

  • Blood cytopenias (deficiency of any of the various cellular elements normally present in the blood)
  • General malaise
  • Lymphadenopathy (swollen lymph nodes)
  • Mild fever

Symptoms depend on the type of virus and the stage of disease. Common general symptoms include:

  • Anemia
  • Blood in the stool
  • Chronic, recurring infections (FeLV-infected cats are susceptible to bacterial, fungal, protozoan, and other viral infections.)
  • Decreased appetite
  • Decreased stamina
  • Depression
  • Diarrhea or constipation
  • Excessive drinking and urination
  • Infertility
  • Jaundice (a yellowing of the skin, whites of the eyes, mucous membranes, and body fluids)
  • Low-grade fever
  • Lymphadenopathy (swollen lymph nodes)
  • Neuropathies, which can cause anisocoria and hind limb paralysis
  • Weight loss

Symptoms in FeLV-infected pregnant cats include:

  • Fading kittens that often develop symptoms that can lead to death within the first few weeks of life:
    • Increased susceptibility to secondary bacterial and viral infections
    • Lack of appetite
    • Lethargy
    • Stunted growth
    • Thymic atrophy (wasting of the thymus gland)
    • Wasting (loss of body mass)
  • Fetal resorption (biochemical disintegration of fetuses)
  • Spontaneous abortion

About 30 percent of FeLV-infected cats develop lymphoid or myeloid tumors (e.g., lymphoma, lymphoid leukemia, erythremic myelosis); lymphoma is the most common. Symptoms of FeLV-infected cats that have cancer include the following:

  • Constipation
  • Cloudy eyes
  • Intestinal inflammation and diarrhea
  • Liver or kidney disease
  • Neurological abnormalities
  • Respiratory distress
  • Vomiting

Publication Review By: the Editorial Staff at

Published: 01 Mar 2001

Last Modified: 16 Dec 2014