Coccidioidomycosis, also called "Canine Valley Fever" is an infection caused by the fungus Coccidioides immitis. The fungus thrives well in sandy alkaline soils in regions with low rainfall, very high temperatures, and low elevation. It is transmitted via inhalation of airborne spores when dogs play in areas where the fungus is present in large numbers. Infection results in a respiratory disease or a disseminated form which can range from mild to severe. Aside from dogs, the disease can also occur in cats and people.

There are two main forms of the disease in dogs. The first one is the respiratory form where the clinical manifestations mainly reflect the presence and colonization of the fungus in the respiratory system. These symptoms include fever, coughing, and depression. As the disease progresses, severe pneumonia might set in.

The second form of Coccidioidomycosis is the disseminated form where the fungal infection can spread to other parts of the body via the blood circulation and cause the swelling of lymph nodes, skin ulcers, inflammation of the eye and its associated structures, weight loss with severe muscle wasting, seizures, lameness, and neck or back pain. The most common organs affected by the disseminated form of the disease include the central nervous system, the bones and joints, the liver, the eye, and the heart muscle.

Diagnosis is based on the clinical manifestations coupled with a complete medical history, thorough physical examination, and results of specific diagnostic tests. Your veterinarian may recommend radiographs, complete blood count, and serum biochemistry test. Identification of the organism by means of cytology, histopathology or culture can confirm the initial diagnosis.

Dogs that suffer from the mild form of Coccidioidomycosis often recover without treatment however there are those that die even after aggressive medical treatment was given. Long term systemic antifungal therapy using ketoconazole, itraconazole, or fluconazole is a part of the treatment protocol for severe cases. Dogs which have recovered from the disease can develop immunity to Canine Valley Fever thus protecting them from re-infection.

Localized infections in the lungs have better prognosis compared to the disseminated form of the disease. Most dogs that recover from the severe form of the infection may have to be given antifungal medication for the rest of their lives.

There is no vaccine which can protect you or your dog from Canine Valley Fever. The best way to prevent infection is to avoid areas where the fungus is present. If you are living in desert regions, keep your dog inside the house on windy days.

Being able to diagnose the early signs and symptoms that your dog will develop before that a minor health issue become a major one is a skill that every dog owner should learn.