Feline infectious anemia is a type of hemolytic anemia caused by a rickettsial microorganism Hemobartonella felis. It attaches to the surface of red blood cells and destroys them. Thirty percent of untreated cats die from this infection. Cats infected with feline infectious peritonitis or feline leukemia are less likely to recover from feline infectious anemia.
The infection often affects young male cats. The exact method of transmission of this disease is not known. It may be transferred from one cat to another by the bite of blood-sucking insects such as fleas, or by the bite of an infected cat. Unborn kittens may be infected through the placenta if the mother harbors the microorganisms. Such kittens may be stillborn, or they may die within a few hours after they are born.
A cat with FIA has fever (103°F to 106°F), appears weak and lethargic and may show signs of anemia (pale gums). Jaundice can occur due to rapid destruction of red blood cells. Cats that recover become carriers and can suffer recurrent bouts of infection or chronic anemia for years. Any cat with anemia can be suspected of having feline infectious anemia. Your veterinarian can make the diagnosis by finding hemobartonella organisms under a microscope on a smear of blood taken from the cat. At times the organisms disappear from the circulation and may not be seen. Accordingly, more than one blood smear might be required to make the diagnosis.
Oral tetracycline is given for two to three weeks. The cat's general condition should improve with appropriate nutritional support. Blood transfusions are indicated if the anemia is severe. Assiciated illnesses should be treated. Steroids are sometimes prescribed if there is an autoimmune component to the anemia.