Valley fever n dogs

How to  minimize the risk of valley fever in your dogs — and yourself.

In 2006, my dogs Shadow, Dasher and I moved from Maryland to southern California for a year. During our six-day drive across the country, we stopped at every possible park along the way. We also drove through the dry dusty land of the southwest, a place of tumbleweed, cactus and blinding windstorms.

When we arrived in California, Shadow was coughing so hard she was gagging. I took her to an emergency veterinary clinic, where it was suspected she had a fungal infection in her lungs. Only a handful of fungal infections are found in dogs: blastomycosis, coccidioidomycosis, histoplasmosis, cryptococcosis, aspergillosis and dandidiasis. Shadow’s symptoms exactly fit one of these – coccidioidiomycosis, otherwise known as valley fever, named for its discovery in the San Joaquin Valley of California.

What is it?

Anyone who has spent any time in Arizona, New Mexico, Texas, Utah, southern Nevada, much of California or the northern Mexican states needs to know about valley fever. It’s caused by the fungus coccidioides, which is found in the soil of areas with low rainfall, high summer temperatures and moderate winter temperatures. The fungal spores become airborne when the soil is disturbed by wind, construction, farming and other activities, including digging. Infection occurs in humans and other mammals when the spores are inhaled.

Valley fever is not contagious, but it can’t be cured and may become a chronic illness. It can be fatal if left untreated or caught too late. Over 400,000 cases occur every year in the southwestern States. It’s often misdiagnosed because physicians and vets may not be familiar with it. Clinical signs include fever, meningitis, loss of appetite, lethargy, bone and joint pain, and difficulty breathing. Depending on the symptoms, it may be confused with lung cancer, tuberculosis, chronic obstructive pulmonary disease, chronic fatigue syndrome and other chronic lung diseases. The coccidioides fungus commonly disseminates to the bones as well as other organs such as the liver, heart, kidneys and brain.

Shadow’s story

Shadow’s symptoms included fever, loss of appetite, lethargy, bone and joint pain, pain in her neck and head (meningitis), masses in her lungs, masses the size of marbles in her heart, lumps in her liver, and possible masses in her kidneys. Although the vet initially suspected valley fever, he refused to believe Shadow had it because her blood titers were repeatedly negative for the infection. Blood titer tests for valley fever are not always positive; if the body is not producing antibodies for an organism, the test will not show an infection.

Over the next three months, I watched my happy, active border collie/Lab mix become critically ill. In desperation, I located and contacted the Valley Fever Center for Excellence (, which is affiliated with the University of Arizona Medical Center in Tucson. The center’s veterinarian urged me to start Shadow on antifungal medication, which would either improve her symptoms or not within a matter of days. (Shadow’s condition was one of those acute and serious cases where a conventional medication was needed to deal quickly with the illness and its symptoms.)

I had a stand-off with the first vet, but would not leave without the antifungal medication. Five days after starting it, Shadow seemed better. I quickly found a new vet who would join me in returning Shadow to health. Over the next three months, her appetite, energy, volume and personality came back. Even more dramatically, the masses disappeared from her heart, lungs and kidneys, although her liver was still inflamed.

Unfortunately, Shadow died a few months later of possible cancer in her liver. Was it caused by the valley fever? We don’t know for sure, but since then, I’ve learned everything I can about this disease. You should too.

Minimizing risk

If you live in an area where valley fever is an issue, here are some common sense suggestions to minimize your chances of infection:

• Stay inside during dust storms and keep doors and windows closed. Be sure to keep your animal indoors too.

• Keep car windows closed when driving on unpaved roads.

• Dust your home regularly with a damp mop or cloth.

• Wet soil before digging in your yard.

• Don’t let your dog or cat dig holes – if you have an outdoor cat, provide him with a litter box in the house so he’ll be encouraged to go to the bathroom there.

• Stay away from dusty agricultural fields and construction sites.

• Keep your immune system, and your animal’s, strong with a high quality diet and purified water, supplements, minimal vaccines, regular exercise, and reduced stress. Strong immunity will also help keep symptoms milder if you or your animal do get infected.


Alice Mees is a certified dog trainer with a focus on canine behavior. She has spent many years volunteering at animal shelters, with animal therapy programs, and with greyhound rescue organizations across the country. She recently started a “Meet and Greet” for Greyhound Rescue in Annapolis, Maryland in order to promote greyhound adoption and educate society about the greyhound racing industry. Her program, Better Dog Behavior, is designed to position dog lovers in a confident leadership role, and enhance communication skills and reestablish trust with their dogs.