Dog care blog

Valley fever in dogs.

NOVEMBER 7, 2026 · 3 MINUTE READ

Valley fever is an infection dogs get by breathing in fungus spores from desert dirt. The University of Arizona estimates it affects 6 to 10% of dogs in Maricopa, Pinal and Pima counties every year.

If you live in the West Valley, your dog lives in valley fever country. Most dogs fight it off. Some need months of treatment. Knowing the signs helps you catch it early.

How dogs get valley fever.

The fungus is called Coccidioides, and it lives in the soil. When dirt gets stirred up by digging, wind, dust storms or construction, the spores float into the air. Dogs breathe them in.

Dogs are at higher risk than people because they keep their noses close to the ground. They sniff, dig and roll in dirt. Pima, Pinal and Maricopa counties make up about 70% of all cases.

Valley fever does not spread from dog to dog or from dog to person. Each infection comes from breathing spores.

How common is it.

A University of Arizona study followed dogs raised from birth in Pima and Maricopa counties. By age 2, 28% had been infected and 6% had become sick.

The university says about 70% of dogs that breathe in the spores control the infection and never get sick.

Signs of valley fever.

Signs often show up one to three weeks after a dog breathes in the spores. Early signs look like a lung infection:

• A dry cough that will not go away
• Fever
• Low energy
• Poor appetite and weight loss

Sometimes the fungus spreads past the lungs. Then you may see limping, swollen joints, skin sores or, in bad cases, seizures. Call your vet if your dog has a cough that lasts, or any of these signs.

Testing and treatment.

Vets usually use a blood test, often with X rays. Each test has limits, so your vet may combine a few to be sure.

Treatment is antifungal medicine, like fluconazole or itraconazole. Most dogs take it for at least six months to a year, and some need it for life. Your vet may check liver blood work during treatment. Relapses happen in up to 30% of cases, so follow up visits matter.

The good news: the University of Arizona says more than 90% of dogs treated for valley fever survive.

Is there a vaccine.

Not on the market yet. Researchers at the University of Arizona made a vaccine that prevented or greatly reduced valley fever in dogs in a 2021 study. Dogs got two shots, 28 days apart.

Anivive, the company working to bring it to market, says the vaccine is waiting on a field safety study before it can be sent for approval. Ask your vet for the latest news.

How to lower your dog's risk.

• Stop digging. Fill holes and redirect dogs that dig.
• Keep your dog inside during dust storms and on windy days.
• Give your dog grass, turf or rock to play on instead of loose dirt.
• Stay away from construction dirt on walks. The West Valley has a lot of it.
• Know the signs and call your vet early.

We see a lot of West Valley yards every week. A clean yard will not stop valley fever, but it is one less thing to worry about while your dog plays outside. See our prices or find your town on our service areas page.

Sources.

• University of Arizona Valley Fever Center: Incidence of infection study
• University of Arizona: A valley fever vaccine for dogs
• University of Arizona Health Sciences: Study shows vaccine protects dogs
• Anivive: Company profile
• PetMD: Valley fever in dogs

Questions.

Can my dog give me valley fever?

No. People and dogs both get it by breathing in spores from the dirt, not from each other.

How long is treatment for valley fever in dogs?

Most dogs take antifungal medicine for six months to a year. Some need it for life.

Is there a valley fever vaccine for dogs?

A vaccine made at the University of Arizona protected dogs in studies. At our last check it was still going through USDA licensing. Ask your vet for the latest.