Ehrlichiosis in Cats

Feline Ehrlichiosis

Ehrlichiosis is an uncommon tick-born disease of cats that is caused by one of several rickettsial organisms that belong to the genus, Ehrlichia. Ehrlichia canis (E. canis) and Ehrlichia risticii (E. risticii) are believed to be the primary causative agents in the cat.

Rickettsia are small microscopic organisms that are different from both bacteria and viruses. They enter various cells of the body and behave as tiny parasites, eventually killing the cell. Ehrlichiosis has been detected in cats in the United States, Europe, South America, Africa, and the Far East.

How cats acquire the disease is not well understood. Ticks have been identified on some infected cats. Although the pattern of development of the disease in cats is not well known, it is believed to be similar to ehrlichiosis in dogs.

What to Watch For

Diagnosis of Ehrlichiosis in Cats

Treatment of Ehrlichiosis in Cats

Depending on the severity of clinical signs, treatment options may include out patient care or may necessitate hospitalization. Antibiotic therapy is the mainstay of treatment for ehrlichiosis in cats. In severely ill patients, intravenous fluid therapy, blood transfusions, and other forms of intensive support may be indicated.

The most common antibiotics used to treat ehrlichiosis belong to the tetracycline family of drugs. They include doxycycline, tetracycline, oxytetracycline, and minocycline. These antibiotics have the greatest efficacy against Ehrlichia, and the fewest side effects. Presently, doxycycline is the preferred drug to use for ehrlichiosis because it is well tolerated in cats. Tetracycline and oxytetracycline may cause anorexia, fever and lethargy in some cats.

Home Care and Prevention

At home, be sure to administer all medication exactly as prescribed and return for follow-up testing as directed by your veterinarian. Most antibiotics are given for at least two to three weeks for this disease. Prognosis is excellent if the disease is caught early. Most cats show improvement within 72 hours of starting the antibiotics. The prognosis for severely ill cats, or for cats with accompanying feline hemotropic mycoplasmosis and lymphosarcoma is poor.

Although the method of transmission of ehrlichiosis in cats is unknown, prevention of tick and flea infestation is recommended. Tick and flea infestation can be prevented by spot-on medications that are applied to the skin, and with sprays or powders. Cats are highly susceptible to insecticides that prevent fleas and ticks. Products designed for use in dogs may be severely toxic to cats, and may result in seizures, collapse, coma, and death. It is important to obtain tick and flea preventive medications from your veterinarian, and to make sure the product labeled as being safe for use in cats.