VALLEY FEVER:
FREQUENTLY ASKED QUESTIONS
By Frank Isom, DVM VCA Northern Animal Hospital
(Editor's Note: Dr. Frank Isom is a BML member who practices veterinary medicine in Phoenix, AZ. He has a lot of experience dealing with Valley Fever and graciously consented to share his knowledge with us.)* What is Valley Fever?
Valley Fever is a disease caused by a fungus, Coccidioides immitis, which exists as a mold found in the soil. Working the soil (ie: construction, gardening) will increase the chances of coming in contact with the fungus. Also, dogs that dig are more prone because they are breathing in all the dirt as they dig.
* Is Valley Fever more prevalent in some areas?
The highest incidence of Valley Fever occurs in the desert areas of the Southwest. The environmental conditions necessary for the survival of the fungus include warm, arid climate, low elevations with small amounts of rainfall and relatively alkaline soil.
* Do you see a lot of Valley Fever in your practice?
Yes, we see a lot of Valley Fever and have maybe twenty or so cases ongoing at all times. I generally see it as a cough, but have seen it show up in many ways.
* What symptoms I should look for?
Because there are two forms of Valley Fever, clinical signs of the disease are variable. The primary form is that which gets into the lungs. With this form, the most common sign is a persistent cough. Many times this is the only sign, but symptoms may also include not eating well, weight loss, fever, or lethargic behavior. Sometimes we see NO clinical signs of the disease until it shows up on blood work.
The other form of the disease is the disseminated (meaning the fungus has spread to other parts of the body). This form most commonly goes to a bone, but can invade the brain, skin, eyes, or almost any other tissue. With this form the animal is usually limping on a limb. Other signs include weight loss, swelling of joints, lack of coordination, seizures, or sudden blindness.
* What tests are run to confirm Valley Fever?
To confirm a diagnosis of Valley Fever, blood tests are needed. X-rays may show a suggestive pattern in the lungs or bones, but blood work is best. It will show not only if the dog has it, but also gives a titer, which shows how bad the infection is. The titer is a good way to measure the response to treatment.
Because of the high incidence of Valley Fever in this area, we test any dog that is ADR (Non-medical term for "Ain't doing right." This is generally a non-specific term for an animal that has no specific complaint except "not himself" or more lethargic, etc.) We also like to test animals before a major surgery, or if they have another medical condition such as diabetes or kidney problems. Valley Fever can complicate an ongoing disease. In addition, we test any animal experiencing seizures before we can say the cause is epilepsy.
* How is Valley Fever treated?
Treatment of Valley Fever can be very challenging. The treatment will vary with the severity of the infection, but generally, treatment consists of oral antifungals. The most common drug is Ketoconazole, but there are many different antifungals available. The primary form (by far the most common form) will require treatment for at least six months and the disseminated form may require lifelong treatment. The cost of the medication may be prohibitive for some owners to continue treatment, as it is dosed by weight and can cost $100 and up per month.
* Is there a chance of long-lasting problems even if my Boxer is treated?
The primary form is generally treatable and has no lasting effects other than mild tissue damage to the lungs. The disseminated form may never be cleared 100%, and will need multiple bloods tests in order to monitor the disease.
* If my dog gets Valley Fever, is she protected from getting it again?
Getting Valley Fever and clearing it does not make a pet immune from getting it again.
* Is Valley Fever contagious?
Valley Fever is not contagious from animal to animal or from human to animal. However, if one dog gets it, it is likely that other animals in that household will come into contact with the fungus , especially if they are in the same yard or all diggers. Another point of information: People can contract Valley Fever and need to see a physician for treatment.
* Is there anything I can do to reduce the chances of my Boxer getting Valley Fever?
There is no known preventative for Valley Fever other than decreasing exposure to the desert soil and dust. This is not always easy, but worthwhile.
Copyright July, 1998 Frank Isom, DVM and the Boxer Mailing List
