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Hepatozoonosis in Dogs

Hepatozoonosis is a protozoal condition spread by ticks.

Hepatozoonosis in dogs is caused by single-celled organisms (protozoa) called Hepatozoon canis and Hepatozoon americanum. The Gulf Coast tick spreads Hepatozoon americanum, and Hepatozoon canis is spread by the brown dog tick.

Dogs are infected by Hepatozoon protozoa when they ingest a tick carrying it or when they eat a bird or rodent with larval tick stages inside of it.

Once the protozoa get inside the dog, they penetrate the intestine and get carried around the body to the spleen, liver, pancreas, lymph nodes, lungs, and muscles.

Signs of Hepatozoonosis in Dogs

A dog that is infected by Hepatozoon protozoa may show the following signs:

  • Fever
  • Lethargy
  • Decreased appetite
  • Muscle pain, weakness, and wasting
  • Eye and nose discharge
  • Enlarged lymph nodes

Hepatozoonosis can have signs that wax and wane. That means the dog may be sick for a bit, appear to get better, and then relapse with similar signs.

Diagnosis of Hepatozoonosis in Dogs

Hepatozoonosis is diagnosed when the organisms are identified under a microscope in a blood smear. A lab test that looks for antibodies to the bacteria can also diagnose it, as can a muscle biopsy. H. americanum can cause changes to a dog's bones that are visible on x-rays.

Treatment of Hepatozoonosis in Dogs

Several medications are used to treat hepatozoonosis in dogs. Antibiotics are sometimes prescribed. Imidocarb, a drug that fights protozoa, may be injected. Dogs may not be completely cleared of the organism, and their signs may need to be treated as they arise.

Pain medications, IV fluids, and anti-vomiting medications may be necessary to support a dog with signs of hepatozoonosis.

A suitable tick control protocol should be implemented to help prevent hepatozoonosis and other tick-borne conditions.

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Watch Out for Ticks This Year

How To Remove Ticks

How to Find Ticks on Your Dog

Lyme Disease in Dogs

Ehrlichiosis in Dogs

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