Bobcat Fever (Cytauxzoonosis)

Bobcats, which live throughout lower Canada, the U.S. and Mexico, act as hosts to the Cytauxzoonosis parasite. Bobcats don’t die from the parasite, but they can transmit it to domestic cats via ticks. Bobcat Fever is usually fatal to domestic cats.

Risk Factors

Ticks present the greatest danger in spring, summer and early fall, particularly for cats that live in or near wooded areas. Outdoor cats are at greater risk because they are more likely to pick up ticks.

Symptoms

Bobcat Fever attacks a cat’s white blood cells, causing them to become distended with the developing parasites. This blocks the flow of blood through small vessels, having an adverse effect on the majority of body organs. The parasite causes blood clotting abnormalities, fluid in the lungs and anemia when the organisms rupture out of the white blood cells where they have been incubating to invade the red blood cells. Cytauxzoonosis symptoms include:

• Decreased activity
• Decreased eating and drinking
• High fever
• Weakness
• Rapid breathing
• Depression or listlessness
• Jaundice (yellow discoloration of gums and skin)
• Pale tissue around the gums, nose and eyes
• High fever with hot skin
• Crying in pain

Symptoms may be mistaken for signs of other diseases such as toxoplasmosis, Mycoplasma and feline infectious peritonitis. The disease progresses rapidly, and death can occur within five days after the first symptoms appear.

Treatment

A diagnosis can be obtained with laboratory tests, but there is no cure. A cat suspected of having Cytauxzoonosis should be brought to the nearest animal emergency clinic immediately, as she will need intensive care 24 hours a day to have a chance of surviving.

Prevention

Bobcat Fever is becoming more common in domestic cats. Given the severity of the disease, it’s important to take precautions:

• Keep cats indoors if possible, particularly spring through early fall.
• Keep grassy areas mowed very short.
• Examine other household pets for ticks—dogs cannot catch Bobcat Fever but they can act as carriers for the ticks that harbour it, and ticks can cause other diseases in dogs.
• Examine human family members for ticks after spending time outdoors.
• If you do let your cat outside during tick season, examine her for ticks when she comes back in and remove them right away if you find any.
• Use a product that kills ticks on all household pets (to be effective, tick control products must contain fipronil).

For more information on cat symptoms, medical conditions, and treatments, visit the Cat Health and Safety page. For a full list of cat articles, see the main Cats page.

This article is provided for informational purposes only and is not intended as a substitute for veterinary consultation and care.