Parasitic infection of the blood cells that result in their destruction, leading on to anaemia, a deficiency of circulating red blood cells.

Signs Your Cat May Have FIA

The disease is most common in young cats, causing weakness and lethargy, with labored breathing and collapse in severe cases. It my be possible to detect a pallor of the mucous membranes such as the gums, and a blood smear will demonstrate the parasite attached to the red blood cells. Some animals may suffer from infection without any signs of illness, which is often brought about, by concurrent infection with another agent such as feline leukaemia virus. The disease often waxes and wanes. At some periods in its course the parasite cannot be found on blood smears, only to multiply again when the cat is stressed.


FIA is caused by infection with a single-celled organism called Haemobartonella felis. It is not proven how it is transmitted from cat to cat, bit the disease is more common in males, it is suspected that bites incurred during fighting may be a possible means. As well as being transmitted by blood-sucking parasites such as fleas.


It can be very difficult to clear this disease completely, but a long course of treatment with an antibiotic such as oxytetracycline will at least help to bring about a remission.