Mycoplasma haemofelis (Haemobartonella felis) is a Gram-negative epierythrocytic parasitic bacterium infecting cats. This parasite does not penetrate the erythrocyte membrane but can erode its surface. The bacteria are transmitted by ticks. The source of infection can be blood transfusion from the infected animal to the healthy one. In cats, the transmission of mycoplasmas is from a queen cat to kittens. There are four phases of the disease:

• phase A: the phase before spreading of the parasites to the bloodstream (it lasts around two weeks);
• phase B: the acute phase, that is, multiple spreading of the parasites into the bloodstream (around 45 days);
• phase C: the recovery phase; and
• phase D: the carrier phase.

In the acute phase, the body temperature rises even to 42°C, and severe anaemia occurs. The bacteria damage the cell membrane of red cells, changing its lipid composition, which causes haemolysis. Mucous membranes are very pale, the filling of blood vessels is poor and tachycardia occurs. Animals can get tired quickly and rest more often. The acute phase can lead to the cat’s quick death (the mortality rate is around 25%). A cat that will recover becomes a carrier. It can be a carrier for many months, and the disease can recur. To avoid that, remember to vaccinate regularly and look after the cat’s health, preventing the weakening of its immune system.