1. Home
  2. Small Dog Health
  3. Canine Valley Fever

Canine Valley Fever

Guest Post by Catherine A. Bono

Canine Valley Fever

Canine Valley Fever, also known as Coccidioidomycosis, is an infection that is – caused by the fungus ‘coccidiodes immitis’.

This fungus can be found in the soil of warm, dry climates such as Arizona, California and parts of Mexico. This fungus can be transmitted to your dog by inhalation.

Once these fungal spores have been inhaled, it can cause a serious respiratory infection. Valley Fever is common in both dogs and humans, and even cats as well.

Valley Fever in dogs works by infecting the lungs. It is known that over 70% of dogs who inhale the Valley Fever spores do not even become ill.

In fact, it is known that once your dog has become infected with Valley Fever, he will become immune to the disease after treatment.

However, those who do become infected with Valley Fever are often very ill and requires immediate medical treatment and therapy.

How Does My Dog Get Canine Valley Fever?

Coccidioidomycosis in dogs, or Valley Fever, is found in warm and dry areas.

This fungus can be found a few inches down in the soil and will remain dormant in rainy seasons. It can be released in the wind, during earthquakes or construction, or any general disturbance of the soil.

It takes under 10 spores of the coccidiodes fungus to infect a dog. The most common times of year for dogs to become infected with Valley Fever are from June to November.

Sometimes, your dog may become infected with Valley Fever but will not be visibly ill.

However, dogs that have weak immune systems, young puppies, and elderly dogs are especially at risk for becoming very sick due to Valley Fever.

Once this fungus is inside the lungs, it will continue to grow and multiply until it creates a serious infection.

Two main forms of Canine Valley Fever

Primary – The respiratory form, which only infects the lungs and respiratory system. If left untreated, dog Valley Fever may cause pneumonia.

Other signs of primary dog Valley Fever include coughing and fever.

Disseminated – The second form of this disease is when the fungal infection spreads to other parts of the body through blood circulation.

This may cause swollen lymph nodes, muscle and joint pain and even seizures. This form of Coccidioidomycosis in dogs is very serious and can result in death if not treated right away.

Symptoms of Canine Valley Fever

Often times, symptoms of Valley Fever in dogs will not even appear. When no symptoms are present, there is usually no need for diagnosis and treatment.

This mild form of dog Valley Fever is not as severe and can usually clear on its own.

The early form of dog Valley Fever are not severe and are usually only respiratory. However, when this infection becomes serious, it can be life-threatening.

If you suspect your dog may be infected with Valley Fever, it is important to keep an eye on his symptoms and behavior.

Even if you notice mild symptoms, it is important to seek treatment to ensure the infection in the lungs does not spread or become worse.

If left untreated, dog Valley Fever can spread to other areas of the body or turn into a lung infection such as pneumonia.

Canine Valley Fever Symptoms

Symptoms may be mild at first but may progress as the infection spreads or worsens. Keep an eye out for the following Valley Fever in dogs symptoms:

  • Difficulty breathing
  • Coughing that starts out dry and may become moist
  • Weight loss
  • Weakness and lethargy
  • Shallow breathing
  • Loss of appetite
  • Shortness of breath
  • Fever

As this infection spreads, or becomes the disseminated form, the symptoms could worsen.

Often times, Valley Fever in dogs symptoms worsen after the infection has been present for more than 4 months. These symptoms include:

  • Diarrhea
  • Vomiting
  • Extreme and recurring fevers
  • Loss of vision
  • Skin sores known as ulcers
  • Swollen joints, especially around the back and neck
  • Limb Lameness
  • Severe cough may contain mucous
  • Seizures
  • Weeping eyes

Some dogs are more at risk for contracting Canine Valley Fever than others.

Dogs who spend a lot of time outdoors or in windy, hot climates may be infected easier, dogs who’s never groomed.

Dogs with a weakened immune system or those who are already ill may become infected easier as well. It is known that males are more susceptible to dog Valley Fever than females.

Breeds such as Boxers, Beagles, Cocker Spaniels and Doberman Pinschers are known to become ill from Valley Fever more than other breeds as well.

Treatment for Canine Valley Fever

Most dogs who become infected with Valley Fever will not even require treatment. In fact, some dogs may even become immune to this disease.

However, when a dog does become ill from Valley Fever, it can become very serious.

To seek Valley Fever in dogs treatment, you will need to keep an eye on symptoms and bring your dog to the veterinarian as soon as symptoms become present.

Your veterinarian will diagnose dog Valley Fever a couple different ways. Your vet will perform a physical exam to check the joints and muscles.

Blood tests may be required if the infection has spread through the blood system. X-rays and radiographs may also be performed to check the lungs and joints.

Once your veterinarian has diagnosed dog Valley Fever, treatment will begin right away.

If your dog is quickly and properly diagnosed, treatment is usually very successful. However, sometimes treatment can take up to a year to complete.

The most important part of treatment is to ensure that the fungal organisms do not continue to multiple and to prevent them from spreading to other areas of the body, otherwise known as becoming disseminated.

Some treatments for Valley Fever in dogs include:

Anti-fungal medication – Oral anti-fungal medications are the most effective form of treatment.

Often times, anti-fungal medications must be given twice a day for 6 months up to a year. In severe cases, sometimes even longer.

Anti-fungal medications require close monitoring and frequent blood testing, as some medications can create serious illnesses in dogs.

Cough medication – If your dog has a severe cough, your veterinarian may prescribe a mild cough suppressant.

Diet – Some dogs may lose their appetite when they are infected with dog Valley Fever. In this case, home cooked meals, hand-feeding or even feeding tubes may be required to ensure your dog is eating enough food. IV fluids may be given as well to ensure hydration.

Antibiotics – Your veterinarian may prescribe antibiotics to ensure a secondary illness does not interfere with treatment for dog Valley Fever.

Pain medication – If your dog has a severe fever, or his joints are sore, your veterinarian may prescribe pain medication or anti-inflammatory medications to ease swelling and pain.


The respiratory form of dog Valley fever has a much higher chance of recovery than the disseminated form. Often times, if the infection is severe enough, dog Valley Fever can be fatal. Seek treatment as soon as you notice any symptoms in your dog.


Guest Author

Catherine A. Bono is a co-founder of crittersitca.com. Our goal is to help as many dog owners (and their dogs!) by providing extensive knowledge for common diseases, conditions and behavioral problems in the form of great content, and a well-designed website.

About Janice (author and voice behind this site)

Having lived with dogs and cats most of her life, Janice served as a veterinary technician for ten years in Maryland and twelve years as a Shih Tzu dog breeder in Ohio.

Her education includes undergraduate degrees in Psychology with a minor in biology, Early Childhood Education, and Nursing, and a master's in Mental Health Counseling.

She is a lifelong learner, a dog lover, and passionate about the welfare of animals. Her favorite breed for over 50 years has been the Shih Tzu, but she has also lived with poodles, Maltese, Yorkshire Terriers, beagles, English bulldogs, carin terriers, and a Cocker Spaniel.

When not writing, reading, and researching dog-related topics, she likes to spend time with her eight Shih Tzu dogs, husband, and family, as well as knitting and crocheting. She is also the voice behind Miracle Shih Tzu and Smart-Knit-Crocheting

Does This Article Deserve Your Thumbs Up?

We always appreciate your support and encouragement.  Your thumbs up means so much to us.  Please like this article.

If you find this page or any page on Small Dog Place Helpful, or useful in anyway, I'd love it if you would click the small heart found on the bottom right of each page.

You can also share or bookmark this page -- just click on the:

10 Mistakes People Make When Choosing a Dog Breed

Free Monthly Newsletter

Sign Up for Our Free Newsletter and get our Free Gift to You.

my  E-book, The Top 10 Mistakes People Make When Choosing a Dog (and how to avoid them)