How to Recognize Valley Fever in Dogs
Valley Fever, also known as coccidioidomycosis, is a fungal infection that affects dogs living in or visiting certain regions of the southwestern United States and other arid areas. Caused by the Coccidioides fungus, this disease can range from mild to life-threatening, so early detection is crucial.
Where Is Valley Fever Found?
This fungus thrives in desert soils and is especially prevalent in:
- Arizona
- California (including Central Valley and Central Coast)
- New Mexico
- Texas
- Nevada
- Utah
- Northwestern Mexico
- Areas of Central and South America
- South-central Washington state
The spores can become airborne when the soil is disturbed by activities like digging or construction. Dogs then inhale the spores, allowing the infection to begin.
How Is Valley Fever Contracted?
Dogs become infected by inhaling spores from the environment. Once in the lungs, these spores turn into spherules, multiplying and potentially spreading throughout the body if the immune system doesn’t control them.
Signs and Symptoms of Valley Fever in Dogs
Approximately 60–70% of infected dogs show no symptoms. However, in more severe cases, symptoms include:
Primary (Pulmonary) Disease:- Persistent dry cough
- Fever
- Lethargy
- Loss of appetite
- Weight loss
These can appear 1–3 weeks after exposure, although they may take longer to manifest.
Disseminated Disease:- Lameness or joint pain
- Swollen lymph nodes
- Back or neck pain
- Eye inflammation or blindness
- Skin lesions or non-healing wounds
- Neurological signs like seizures
- Swollen testicles
- Signs of heart failure
Which Dogs Are Most At Risk?
Young puppies, senior dogs, and those with compromised immune systems are at increased risk for developing severe Valley Fever. Dogs that frequently dig or sniff soil are also more susceptible.
Diagnosing Valley Fever
Because symptoms can resemble other illnesses, accurate veterinary diagnosis is key. Diagnostic methods include:
- Blood tests for antibodies (serology)
- Chest X-rays
- Cytology (microscopic examination of affected tissues)
- Fungal cultures
Additional lab work or imaging may be required depending on the dog’s symptoms.
Treatment Options
Treatment generally involves long-term use of antifungal medications like:
- Fluconazole
- Itraconazole
- Ketoconazole
Severe cases may need treatment lasting 6 to 12 months or more. If the disease affects the central nervous system, lifelong therapy might be necessary. Vets also recommend monitoring liver function during treatment. Additional supportive care—such as anti-inflammatory drugs, IV fluids, or pain management—could be required.
Prognosis and Recovery
- Over 90% of dogs with only pulmonary involvement recover well with appropriate treatment.
- Dogs with disseminated or neurological forms have a guarded prognosis.
- Relapses can happen, necessitating follow-up care.
Prevention Strategies
You can reduce your dog’s risk by:
- Limiting outdoor exposure during dust storms or soil-disturbing activities
- Using ground covers like mulch or gravel
- Preventing dogs from digging or sniffing rodent holes
- Keeping pets indoors in endemic areas
A vaccine for Valley Fever in dogs is under development, offering hope for future prevention.
When to See a Veterinarian
If your dog shows any respiratory or unexplained symptoms and you live in or recently traveled to an area where Valley Fever is common, consult your veterinarian immediately. Let them know about your location and travel history to aid with accurate diagnosis and timely treatment.
Early detection and intervention can vastly improve the outcome for your dog.
