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Symptoms, Diagnosis, and Treatment of Valley Fever in Dogs

Dogs who live in the Southwestern United States and Mexico can be at risk for Valley Fever.

Dogs who live in the Southwestern United States and Mexico can be at risk for Valley Fever.

What Owners of Dogs Living in the Desert Should Know

We learned about the symptoms of Valley Fever in dogs the first months we started living in Arizona. It all happened one morning when our five-month-old puppy, Kaiser, woke up and started to limp. Not much concerned, we thought his foot perhaps had fallen asleep or perhaps he was a bit sore from sleeping on it.

The limping seemed to subside for a week, but then it came back with a vengeance. Since he still was putting weight on his leg and playing normally, I thought to give it a couple of days, assuming it was a sprain. The following day though, Kaiser was reluctant to get up, appeared sluggish, and suddenly developed a cough as well. Very concerned at this point, and baffled by the odd symptoms, we took him to see the vet.

The veterinarian performed a careful physical exam and checked for any broken bones in his paw. He also listened to his lungs. Afterward, he decided to take an x-ray of his foot and of his chest. After what felt to be an hour, he came back with a serious look on his face. I had that cold feeling that something was seriously wrong.

"His foot has some deformities, you see how the digits of his fingers are slightly crooked?" he said pointing out some obvious deformities in the lit-up x-ray in the darkroom. Then he took the chest x-ray and showed some clouded areas denoting inflammation of the lungs.

Puzzled by these odd symptoms, I knew this was not just a case of growing pains with a touch of kennel cough. The vet highly suspected a case of disseminated coccidioidomycosis, a fungal condition better known as Valley Fever.

The vet added that while this was likely the scenario, this had yet to be confirmed by some blood tests. He also kindly told me that if this was really Valley Fever, the treatment was going to be very costly. Thank God I had just enrolled Kaiser in a pet insurance plan! I had many questions in my mind, but I conducted further research on my own.

Digging puts dogs at risk for inhaling the spores and getting Valley Fever.

Digging puts dogs at risk for inhaling the spores and getting Valley Fever.

What Is Valley Fever in Dogs?

Valley Fever is a disease of the dusty areas of the Southwestern United States and Mexico. It is caused by a fungus whose spores are spread by the air. Upon inhaling dust, these spores transform into a broader multi-cellular structure called a spherule, which will develop endospores that will turn into spherules again, repeating the cycle over and over again.

The spores are mostly released when the terrain is disturbed. This is why humans, construction workers, archaeologists, and utility workers are most affected.

In dogs, on the other hand, simply playing in the sand is sufficient to inhale the dangerous spores. Kaiser was sure an avid digger. He used to play for a good part of the day in the sand and roll in it. I did not know anything about this dangerous disease until moving to Arizona!

And to make things worse, my whole yard was recently cleared from trees and bushes with a backhoe by a landscaping company, further disturbing the soil.

Yet, my vet said I could not blame myself, because the spores are also transported by winds and the dust devils that are so common here in Arizona in the summer months.

"Infection is most likely to occur in the summer months when hot, dry conditions favor inhalation of arthroconidia (a type of fungal spore) spread by wind or physical disturbance of infected soil. In the United States, the endemic area for coccidioides immitis includes parts of California, Nevada, Utah, Arizona, New Mexico and Texas."

— Alice M. Wolf and Gregory C. Troy

Signs and Symptoms of Valley Fever in Dogs

  • Fever
  • Cough
  • Lethargy
  • Inapettence
  • Weight loss
  • Lameness (when spreading to the bones)
  • Seizures (when spreading to the brain)

Incubation Period and Potential Spread From Lungs

The symptoms of Valley Fever in dogs generally arise within one to three weeks following exposure. The early signs might not be noticeable at first.

Most cases of Valley Fever are self-limited and mostly confined to the dog's lungs, but this disease may easily spread to other locations causing the disseminated form of this disease.

In Kaiser's case, the disease spread from his lungs to his bones, affecting his foot and causing the visible limping that had progressed over the days.

Valley Fever is no fun!

Valley Fever is no fun!

Diagnosis and Treatment for Dog Valley Fever

A few days later, the vet called with the bloodwork results. He confirmed that his bloodwork indeed came back positive for coccidioidomycosis. However, his titer level was four, fortunately suggesting a mild form of Valley Fever.

My dog was put on an antifungal medicine called fluconazole. This was the expensive part of the treatment: each pill of fluconazole can cost up to 20 dollars! The vet told me he could be put on ketoconazole or itraconazole, but he said that fluconazole had the least amount of side effects and worked best.

I was determined to allow my dog to heal well, so I bought that expensive bottle of fluconazole. Later, I found a great compounding pharmacy that sold me a 60-day supply of fluconazole for less than $25 dollars!

Kaiser was kept on fluconazole for the next six months. The vet told me that in some cases, dogs may need the medication for life. Luckily, my dog had improved greatly since the first week on the antifungal medicine.

If you see him today, he acts and looks like a normal dog. He yet has to have his last blood test in a few weeks though. The results should determine if he must continue the medicine or stop it altogether. I am hoping for the best.

So, if you should move to any desert areas of the great Southwest such as Arizona, Texas, New Mexico, or California, please do not underestimate this disease. While in most cases, dogs may develop only a mild fever and cough, in some cases the disease may turn deadly if treatment is not sought in time. Also, be aware of the symptoms that can happen in humans too!

While there is not much you can do to prevent this disease, you can take action quickly should your dog develop typical symptoms suggesting Valley Fever. In general, the quicker the diagnosis, the better the prognosis.

Vet Talks About Valley Fever in Dogs

This article is accurate and true to the best of the author’s knowledge. It is not meant to substitute for diagnosis, prognosis, treatment, prescription, or formal and individualized advice from a veterinary medical professional. Animals exhibiting signs and symptoms of distress should be seen by a veterinarian immediately.

Questions & Answers

Question: Where can I get Fluconazole for less than $25.00?

Answer: It may be cheaper if you get if from a compounding pharmacy. Foothills Compounding Pharmacy or Diamondback Pharmacy may offer a cheaper option. It may be worth it calling to ask. Dr. Foster's and Smith at present time sells Fluconazole at the price of $1.59 for a 50mg pill.

Question: Can I still breed my female after she’s had valley fever?

Answer: The most commonly prescribed medication for dogs with Valley Fever is drug known as fluconazole. Fluconazole should not be given to pregnant or nursing dogs or to a dog that you plan to breed. Your dog should have a titer test done to ensure she no longer has Valley Fever. The titer test measures how many antibodies your dog is making against the fungus. At that appointment, based on the results, you can then ask your vet whether it's OK to breed her or wait for another titer test to make sure she is in the clear.

© 2008 Adrienne Farricelli


Adrienne Farricelli (author) on April 03, 2019:

Debbie, that was 8 years ago, so not sure what the company was. I think Reed's compounding pharmacy in Tucson may get a good deal. Worth asking.

Karen on February 19, 2018:

Add Your Comment. Miley's 9 years old female diagnosed with valley fever and her lip she's on her medication but I feel she's in pain what can I give her

Adrienne Farricelli (author) on January 25, 2018:

John, follow up with your vet. He/she needs to know what is going on. In my dog's case, the cough didn't last that long.

johnfrantay on January 20, 2018:

My dog has valet fever and has been treated for six weeks. Her cough improved for awhile but know it came back, worse than ever. How long does it take for the cough to go away? Could she need a stronger does?

John on January 20, 2018:

My dog has been on medicine for six weeks. The cough improved but recently go worse. How long before it should go away? Or could the dose be too weak?

Adrienne Farricelli (author) on November 14, 2017:

Stacy, here are hopes that your dog is doing well. The airborne version of Valley fever in dogs in Florida is known as? I am interested because I wasn't aware of this occurring in Florida. I have only heard of blastomycosis and histoplasmosis, but don't think they're much common in Florida.

Stacy Harris on June 01, 2017:

They also have an airborne version of this as well in Florida. We are waiting to have more invasive testing done on my dog to see if he has this or if he has bone cancer. He is a shell of a dog compared to the vibrant, beautiful, lively dog he was just a few months ago. I'm praying at this point he just has this airborne virus.

Adrienne Farricelli (author) on October 11, 2014:

Thank you for the information. I will spread it out, I am sure many dogs would benefit from the preventive vaccine, I hope they make one for people too! on October 10, 2014:

Read all about the University of Arizona's new canine vaccine at:

Adrienne Farricelli (author) on November 27, 2013:

Luckily, my dog's blood test revealed that my dog was free of this disease after several months. He is no longer on flucanazole.

Adrienne Farricelli (author) on March 06, 2012:

I wished there was more literature on this as well. My dog got it and I did not know of the disease, otherwise I would have not let him play in the sand! Is your dog being treated with flucanazole?

ann on March 06, 2012:

Just spent a month in Arizona and returned home to Montana with my 3year old golden retriever has a very nasty case of desert fever. I am watching her become a shadow of the beautiful healthy dog she used to be. She has become very thin and lathargic. She has been on mere for three weeks and continues to fall victim to the fungal infection....very sad to be so helpless against a disease that is so hidden from travelers to Arizona desert areas. A little notification of the dangers would have helped me avoid the pain I and my best pal are going through would have been considerate.

bonnitta on December 11, 2010:

thank you for this information, i am visiting arizona and have just learned of this serious possibility. i will watch my dogs for any symptoms.