Cat Feline Infectious Anaemia | Animal Welfare Hub

Feline infectious anaemia caused by Mycoplasma haemofelis causes haemolytic anaemia requiring rapid diagnosis and treatment.

Key Facts

Mycoplasma haemofelis attaches to red blood cell surfaces, triggering immune-mediated haemolysis.
Outdoor cats are at higher risk through flea and tick transmission.
Clinical signs include lethargy, pale or yellow gums, reduced appetite, and weakness.
Diagnosis is by PCR testing of blood; Coombs' test may detect the immune-mediated component.
Treatment with doxycycline for 4-6 weeks eliminates the organism; prednisolone reduces immune-mediated destruction.

Welfare Considerations

Mycoplasma haemofelis anaemia develops rapidly and causes significant welfare compromise through profound weakness, dyspnoea from anaemia, and the distress of severe lethargy. Affected cats may require emergency blood transfusion to stabilise before treatment can take effect. Tick and flea control is the primary preventive measure for outdoor cats. The concurrent immune-mediated component — where the cat's own immune system destroys infected red cells — requires immunosuppressive management. With appropriate treatment, most cats recover fully, but treatment must be of adequate duration to prevent relapse. Regular parasite control is the most important welfare intervention to reduce transmission risk.

What You Can Do

Maintain year-round flea and tick control in outdoor cats to reduce Mycoplasma haemofelis risk.
Seek urgent veterinary attention for any cat showing lethargy, pale gums, or rapid breathing.
Request PCR testing for haemoplasmas if your cat has unexplained haemolytic anaemia.
Complete the full 4-6 week doxycycline course to prevent relapse after apparent recovery.