When fleas cause more than just an itch

No one likes fleas - they cause itching and distress to our pets and sometimes to us. They also cause significant skin disease in allergic pets. What you may not be aware of is the potential killer that they carry in their saliva.

Feline infectious anaemia is caused by a parasitic bacteria called Mycoplasma haemofelis. A cat becomes infected with this by a bite from an infected flea.  The bacteria attaches to the red blood cells and multiplies in the cats blood stream.  Soon the red blood cells are coated in the parasite - the immune system senses that these cells are sick and kills them by removal in the spleen.  When enough red blood cells have become infected and destroyed the cat becomes anaemic (a low red blood cell count).

Anaemia makes the cat feel weak and lethargic as the life force of oxygen is not carried to their organs. They often breathe quickly, sleep a lot and stop eating.  Sometimes anaemic cats will start to eat cat litter or dirt to obtain iron, which is lost when red blood cells are destroyed.

On examination the vet will find pale gums, a fast heart rate with a murmur, increased breathing rate and effort and sometimes a fever. Cats are very good at hiding disease and may be very ill before you notice it.

Diagnosis is made by clinical examination and a blood test, looking at red blood cell levels.  We have seen cats with a red blood cell count of just 7% (normal is 27-47%) - this can be life threatening.  Sometimes the parasite is visible on a blood smear as small dark spots inside the cell. These are not always visible as the parasite numbers vary markedly as the numbers cycle from hour to hour even in heavy infections.

Treatment may require a blood transfusion - not always easy in our feline patients. Very ill cats are kept in hospital on oxygen and handled very carefully, as they can suddenly deteriorate with stress. An antibiotic called Doxycycline is used to stop the parasite from multiplying, and steroids prevent more destruction of cells by the immune system. Treatment can be complicated if the cat has feline aids or leukaemia viruses.

Of course prevention is better than cure - and regular application of an effective flea treatment is the only defence. Totally Vets are always happy to discuss an effective treatment programme for fleas in all your pets.

Mycoplasma heamofelis

Mycoplasma haemofelis as seen under the microscope

Understanding flea control