Valley Fever in Pets: What North Dakota Pet Owners Need to Know Before Traveling South
Fungal infections from the American southwest have been seen more frequently in some of our patients. Here’s what you need to know.
Understanding a Risk for Pets Visiting Arizona and Other Southwestern States
At Two Rivers Vet Hospital in Fargo, we occasionally diagnose a condition that doesn't originate in the Midwest—but it can still affect our patients: Valley Fever. If you and your pet travel to Arizona, New Mexico, Texas, or California, this blog is for you.
What Is Valley Fever?
Valley Fever is the common name for a fungal infection caused by Coccidioides organisms found in dry, dusty desert soil. Dogs are most commonly affected, but cats and humans can be, too.
This fungus lives in the soil and becomes airborne when the ground is disturbed — for example, by digging, hiking, or even during windy days. Pets breathe in the fungal spores, which then settle in the lungs and begin to grow. From there, the infection can remain localized or spread (disseminate) to other areas like bones, eyes, skin, or the nervous system.
Where Is Valley Fever Found?
Valley Fever is endemic to certain areas of the southwestern U.S., especially:
Arizona (especially Phoenix and Tucson)
New Mexico
Southern California
Western Texas
If your pet has traveled to or spent time in these areas — even briefly — they could be at risk for infection.
Symptoms of Valley Fever in Pets
Valley Fever symptoms can take weeks to months to appear after exposure. Because they’re vague, the condition is often misdiagnosed or mistaken for other diseases. Common signs include:
Coughing or trouble breathing
Fever that doesn’t respond to antibiotics
Lethargy and weakness
Lameness or swollen joints
Weight loss or poor appetite
Enlarged lymph nodes
Seizures or neurological signs (if the fungus spreads to the brain)
In cats, symptoms may include skin lesions, draining wounds, or respiratory signs.
👉 If your pet has any of these symptoms and recently visited Arizona or similar regions, talk to your veterinarian immediately.
Diagnosing Valley Fever
Diagnosis usually involves:
Blood tests for Coccidioides antibodies
X-rays of the lungs or limbs
Biopsies or fungal cultures in some cases
Because it mimics other conditions like cancer, pneumonia, or tick-borne illness, a thorough travel history is key to reaching the correct diagnosis.
How Is Valley Fever Treated?
Treatment for Valley Fever involves long-term antifungal medications, most commonly fluconazole. Most pets require at least 6–12 months of treatment — and some may need lifelong therapy if the disease has spread beyond the lungs.
Because these medications can stress the liver, your veterinarian will schedule regular blood work to monitor your pet’s liver enzymes and assess response to treatment.
Can Valley Fever Be Prevented?
Unfortunately, there is no vaccine for Valley Fever. The best prevention is limiting your pet’s exposure to dry, dusty areas when traveling:
Avoid letting dogs dig in soil or run off-leash in desert environments.
Keep pets indoors during dust storms.
Choose pet-friendly travel activities that don’t involve hiking in endemic areas.
When to See a Veterinarian
If your pet starts coughing, limping, or acting tired after traveling to the Southwest, don’t wait — schedule an appointment with your veterinarian. The earlier Valley Fever is diagnosed, the better the prognosis.
