If your cat gets all its shots regularly, feline leukemia should
never be a problem. Along with rabies and distemper, it's part
of the standard shots given during vaccination. The most serious
thing about feline leukemia among unvaccinated cats is the fact
that it's contagious. Transmission comes through an exchange of
blood, urine, or saliva. Feline leukemia doesn't usually kill
cats. It only makes them less resistant to infections and
cancers that do. Symptoms will vary from cat to cat, but
generally include lethargy and loss of appetite. If you have
your kitten vaccinated when it's nine or ten weeks old and give
it regular booster shots when the veterinarian recommends,
feline leukemia should never be a problem.