Feline leukemia is a high-mortality disease caused by the feline leukemia virus (FeLV). FeLV produces an initial immunosuppressive infection followed by various other diseases (e.g. respiratory disease, diarrhea, anemia) affecting the immunosuppressed cat. Cats that survive these initial diseases may develop some form of cancer, hence the name feline leukemia. The disease is transmitted by direct contact with infected cats or with contaminated food dishes or litter boxes. Feline leukemia vaccination is now commonplace.