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Valley Fever and Arizona Pets

Living in the desert has its advantages. No snow to shovel, few fleas and mosquitoes and amazing sunsets. But one of the disadvantages of our environment is a fungal infection that dogs, people and the occasional cat is susceptible to: Valley Fever.

Valley Fever is a nickname for a systemic fungal infection. The name of the fungus is actually Coccidioides immitis. In dogs, the target organ can vary greatly. Most cases we diagnose have infection in the bones. Lungs are frequently affected as well. Because of the unpredictable course of this disease, many dogs that have vague symptoms are tested for Valley Fever.

“Fungal infections” are different than bacterial infections, therefore, standard antibiotics are of no value in treating a fungal infection. Anti-fungal medications most commonly used are fluconazole, itraconazole and ketoconazole. Each has its place but by far and away fluconazole is preferred for treating Valley Fever.

How does my pet become infected?

The source of infection is a fungal spore that lives in the desert soil. Just living here is enough to expose and potentially infect a dog. But if a dog digs in the dirt he or she is more likely to become infected. Some breeds seem to have a greater tendency to contract Valley Fever (in my opinion). Boxers are such a breed.

Can I “catch” Valley Fever from my pet (or visa versa)?

We all become infected the same way; by inhaling the spores from the soil.

Do all dogs that become infected need treatment?

No. Actually most dogs are exposed, become ill for a very short time and develop immunity after that. Only a small percentage of dogs (and a very small percentage of cats) become systemically infected.

How do you diagnose Valley Fever?

Presently, testing for the presence of a high titer to this specific fungus is how the diagnosis is made. “Titer” means the body has been exposed to a pathogen and is mounting a defense. The higher the titer, the more widespread the infection is likely to be.

If infected, is this disease fatal to dogs?

Occasionally a pet succumbs to Valley Fever. Most of the time treatment is successful. The treatment does require commitment as the medication needs to be given for months.

Is the medication expensive?

Cost is a big concern in the treatment of any chronic infectious disease. Besides the cost of the medication itself, most pets require radiographs and other testing. The good news is that there are many reputable pharmacies that “compound” or mix the drugs in a specific dose for each individual pet. Several years ago our clients faced prohibitive costs for the name-brand medication.

What else do I need to know?

Valley Fever is common. We diagnose a new case on the average of 3-4 times each month. In most cases, it is manageable. Each pet responds in his or her own way. Don’t be discouraged.


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