Trypanosomiasis in Dogs; Tse-Tse Fly Transmission

Dogs in tropical Africa run the risk of contracting canine trypanosomosis if they are bitten by bloodsucking tsetse flies carrying trypanosomes – microscopic, single-celled organisms found in the bloodstream. In dogs, this disease runs a severe course and is often fatal; “white eyes” or corneal cloudiness is one of the characteristic and obvious signs of the disease.

Tsetse are small, winged biting flies that feed on the blood of humans and other animals. Infected tsetse flies inject the protozoa into the skin of animals, where they grow for a few days and cause localized swellings called chancres. They enter the lymph nodes, then the bloodstream, where they multiply quickly. The immune response is very strong; however, not all trypanosomes are vulnerable to the immune response, which results in longterm infection.

African trypanosomosis (CAT), particularly are common in indigenous dogs (mongrel breed).

Symptoms of Trypanosomiasis in Dogs

Acute symptoms to watch out for include:

• Depression – your dog may seem disinterested in what is going on around him

• Lethargy – lacking energy and just wanting to sleep
• Your dog may have a fever
• He may suffer from diarrhea
• Loss of appetite
• Enlarged liver or spleen – seen on tests or scans
• Neurologic abnormalities – he may suffer seizures
• Sudden death

Treatment and Prevention

Several drugs can be used for treatment; however, most drugs only work if the correct dose is given. It is very important to follow the prescribed dosage exactly. Some trypanosomes have become resistant to certain drugs, which may be the cause in cases that do not respond to medical treatment.

Disallowing consumption of raw meat and eliminating dog contact with vectors by using topical repellents and insecticides such as collars and spot-on formulations.

Tsetse flies can be partially controlled by frequent spraying and dipping of animals, aerial and ground spraying of insecticides on fly-breeding areas, use of insecticide-impregnated screens and targets, bush clearing, and other habitat removal methods