Leukemia is a grouping of different cancers that begin in the bone marrow, and cause extremely high levels of white blood cells to enter circulation. There are 4 main types of leukemia, and while experts aren’t certain of the cause of them, it’s believed to be some combination of genetics and environmental exposures to things like ionizing radiation and other carcinogens like cigarette smoke and some chemicals. One thing is for certain though, leukemia is definitely not contagious.
Unless you’re a cat.
Cat’s can be infected with a virus called Feline Leukaemia Virus (FeLV), a virus which, if not fought by the kitty’s immune system before a certain infection stage, can cause secondary infections, anemia, weight loss and lymphomas (cancer of the lymph nodes). FeLV is very contagious, and it’s spread through bodily fluids like blood, saliva and milk, meaning that cats can be exposed during fights, nursing or even just sharing bowls. Kitties with FeLV usually only live about 1-2 years longer after being infected, though some rare cases have left cats to live their entire natural lives.
Before you get too scared for your cat however, you should know that many cats that become infected, actually fight off the virus just fine. About 70% of cats who are exposed to FeLV either fight the infection effectively or have natural immunity. There is also a vaccine, that while not 100% effective, has been shown to reduce risks of infection greatly. It’s not currently recommended for all cats, mostly because indoor cats have very little chance of exposure to FeLV. If you do have outdoor cats or multiple cats who aren’t all FeLV positive, the vaccine could greatly reduce their risks of infection.
Treatments for FeLV infected cats are a lot like the treatments for humans with leukemia. Chemotherapy can be given to cats with cancer, and other treatments can be prescribed by a vet as they become needed (like antibiotics for secondary infections, or iron supplements for anemia). Experimental treatments are always being developed too, though none show too much promise currently, just like human cancer treatments, the science is ever evolving.
Thecat pictured is named Chester and he has FeLV, but that doesn’t mean he isn’t a wonderful companion! If you have no other cats and are willing to keep him indoors, then you’ll barely know he has it. He has found his forever home, but several of his incredible FeLV friends (and nonFeLVfriends) are available for adoption here