Feline Leukemia – Symptoms
Feline Leukemia does not show up in a cat’s blood tests until at least four weeks following exposure. Eighty percent of exposed cats become infected within 20 weeks of exposure. When illness does develop, it manifests itself with non-specific signs and lasts anywhere from two to 16 weeks. Signs include fever, apathy, weight and appetite loss, vomiting, constipation or diarrhea, enlarged lymph nodes, anemia and pale mucous membranes. These symptoms may be mild enough to escape detection.
One of the following two tests may be used to diagnose the FeLV virus:
- Immunofluorescent antibody (IFA) test – This test detects the virus antigen in infected white blood cells. If the antigen is present, the bone marrow is infected and the cat is most likely chronically infected and shedding the virus in his saliva. Almost 100 percent of these cats remain chronically infected for life.
- Enzyme-linked immunosorbent assay (ELISA) test – This test detects the antigen in whole blood, serum, saliva or tears (blood is the most favored of the four substances) and is more likely to detect weak, early or transient infections. Any positive ELISA test should be confirmed with an IFA test to determine whether the cat is infectious.
The ELISA test should be repeated in eight to 12 weeks’ time to confirm whether the virus is still present in the cat’s system. It is also advisable to repeat the IFA test at the same time, since the infection may not have been detectable at the time of the first test. Latent infections can be diagnosed only through a bone marrow test.
