Well, here's what I've found on it being transmitted to humans:
"Q: I have friend with cat with feline leukemia....her vet said there was an increased incidence of leukemia in children where cats with this disease were around? is this true???? never heard of it and can't imagine it lives long enough to cause problems in humans... Thanks, BMan
There was an exchange in the letters to the editor (I think that is where it occurred) section of a veterinary journal in which this claim was made. It was apparently based on a British study in which children with leukemia were studied for factors that might have contributed to their disease. Children with cats were more likely to have leukemia in that study but to the best of my knowledge (I have only seen reference to this in a textbook, not the article) there was no mention of this being from feline leukemia virus. Many other studies have been done since this one and none have shown any evidence that feline leukemia virus can cause leukemia or lymphoma in humans. I truly believe that this information is simply incorrect.
Mike Richards, DVM "
"Epidemiological and laboratory studies have failed to provide evidence that FeLV can be transmitted from infected cats to humans. Regardless, FeLV-infected cats may carry other diseases. At greatest risk of infection are elderly or immunosuppressed people (e.g., those with AIDS, or receiving immunosuppressive medications such as chemotherapy), infants, and unborn children. It is recommended that pregnant women, people with suppressed immune systems, the very young, and the very old avoid contact with FeLV-infected cats. "
And this is what it is:
"Feline leukaemia virus (FeLV) is a common and important cause of illness and death in pet cats. Cats that become persistently (permanently) infected with this virus are at risk of developing many severe illnesses such as anaemia and cancer. Between 80 and 90% of infected cats die within three and a half years of being diagnosed as having FeLV.
The most common effect of infection is immunosuppression. The virus infects cells of the immune system (the white blood cells) killing or damaging them. This leaves the cat vulnerable to a wide variety of other diseases and infections (secondary infections). FeLV is a member of the same virus family as feline immunodeficiency virus (FIV). "
It's basically feline leukemia. Hope that helps