Feline Leukemia Symptoms

Feline leukemia is a devastating and contagious illness among domestic cats. The virus decimates the immune system, exposing infected pets to a host of other pathogens. It is a leading cause of cancer in cats and is also linked to several blood disorders. While there is no cure for feline leukemia, testing and vaccinations are available to help owners prevent the disease in their pets.

Stray cats family
Feline leukemia is most common in feral colonies and other large groups of cats.
credit: Martina_L/iStock/Getty Images

About Feline Leukemia Virus

Feline leukemia virus is a retrovirus, which means that it reproduces by inserting its DNA into the genes within the the host's body. It harnesses the power of its victim's cells to multiply rapidly. The infection weakens your cat's immune system significantly, which creates an opportunity for other diseases to develop. Bacteria that were once benign can become a fatal threat to cats who lack immune defenses.

Common Symptoms

Due to the nature of FeLV, it is notoriously difficult to identify based on visible symptoms alone. Frequent colds and other infections are a red flag for veterinarians, who may request testing on frequently sick animals. Consistent weight loss, inflamed lymph nodes, digestive distress and eye problems are all common signs of feline leukemia, according to Cornell University College of Veterinary Medicine. While symptoms can emerge soon after infection, some cats carry the virus for weeks or months before showing symptoms. Many visible symptoms in infected cats are produced by secondary infections that develop after FeLV is established.

Managing Infection

Not all felines who contract the virus become permanently ill. In some cases, the virus causes a latent infection that only flares temporarily during periods of stress or illness. Cats with a persistent, active infection develop visible symptoms as the disease progresses. These animals suffer from a compromised immune system and often pass away within three years of diagnosis, according to the Virginia-Maryland Regional College of Veterinary Medicine. Feline leukemia can't be cured, so management strategies center around supportive care and dealing with secondary infections as they arise. Consult with a trained veterinary professional to identify and treat your pet's condition.

Testing and Vaccination

You should test cats and kittens for FeLV before bringing them home or housing them with other felines. Tests on young cats can produce false negatives, so kittens should be kept isolated until the test can be repeated a month or two after the first. While vaccinations don't confer complete protection from the virus, some owners use this tool to reduce the risk of infection in their pet. The first course of the vaccine requires two shots in a three-week period, followed by annual boosters.