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How to Prevent Valley Fever

How to Prevent Valley Fever

Valley fever is prevalent across the Southwestern states and can infect people, dogs, cats, and livestock. In this post, our Moreno Valley vets discuss the causes, signs, and treatment of Valley Fever in pets.

Valley Fever in Cats & Dogs

Coccidioidomycosis is a condition seen in dogs, cats, livestock, and people that goes by several different names including Valley Fever, desert rheumatism, San Joaquin Valley Fever, and California disease. 

Valley Fever is caused by a pathogenic fungus called Coccidiodes immitis that lives in the soil and thrives in particular desert climates. In the US Coccidiodes immitis can be found in the low desert regions of New Mexico, Texas, California, and most especially in Arizona.

Our vets at Sunnymead Veterinary Clinic see Valley Fever in both dogs and cats, although less frequently in cats. It is estimated that for about every 50 dogs with Valley Fever, our Moreno Valley vets will see 1 case in cats.

It is important to seek veterinary assistance as soon as your pet is showing signs of Valley Fever. Left untreated, your pet may require urgent medical care and the disease can become fatal.

How Pets Contract Valley Fever

Pets develop Valley Fever when they breathe in Coccidiodes immitis fungal spores. When the spores are inhaled by your dog or cat they grow into spherules within the pet's lungs.

In dogs and cats that have a strong and healthy immune system, the body is typically able to 'wall off' the spherules preventing symptoms from developing. This means that the pet may have the condition but have no symptoms of Valley Fever, known as asymptomatic.

If your pet is very young, old, or has a compromised immune system the spherules will likely continue to grow until they eventually burst, releasing hundreds of endospores that can spread throughout the lungs and other parts of your pet's body where the cycle will begin again and the condition will become increasingly severe.

Transmissibility of Valley Fever

Valley Fever in dogs and cats is not contagious between pets, and can only be contracted through the inhalation of spores.

Symptoms of Valley Fever in Dogs & Cats

Although the symptoms of Valley Fever may have some similarities between dogs and cats, there are some key differences.

Signs of Valley Fever in Dogs

In the early stages, when the spherules are contained within the lungs, symptoms of Valley Fever in dogs typically include:

  • Fever
  • Lethargy
  • Decreased appetite
  • Dry cough
Once the fungal spores have reached other parts of your dog's body the signs of Valley Fever in dogs may become more severe and could include:
  • Painful swollen joints
  • Eye inflammation
  • Weight loss
  • Persistent fever
  • Blindness

In some very rare severe cases, if the fungus reaches the brain, Valley Fever can cause seizures.

If your dog is displaying symptoms of Valley Fever it is essential to seek veterinary care as quickly as possible to avoid serious health complications.

Signs of Valley Fever in Cats

As mentioned earlier, Valley Fever is less common in cats than it is in dogs. When this illness does occur in cats it tends to be in younger active outdoor cats since the spores are typically found below the surface but become airborne if that cat digs or during very windy conditions. 

Common symptoms of Valley Fever in cats include:

  • Non-healing skin lesions that look like abscesses or dermatitis and may ooze a pale yellow to reddish fluid
  • Coughing
  • Breathing difficulties
  • Behavioral changes
  • Limping
  • Lethargy
Cats with Valley Fever seen by our Moreno Valley vets tend to get sicker than dogs. This may be because it can be more challenging to detect when a cat is feeling unwell, so pet parents begin noticing symptoms only when the condition is more advanced.

Treatment for Valley Fever

The treatment for both dogs and cats with Valley Fever will typically include an anti-fungal medication such as fluconazole or itraconazole. Dogs may also be treated with ketoconazole but this is not well tolerated by cats.

Treatment of Valley Fever in pets takes quite a long time. The majority of pets will need to be taking antifungal medications for a minimum of 6 - 12 months. If the condition continues to spread through the body, there is the possibility that your pet may need to be on this medication for the rest of their life.

Is Valley Fever Curable in Pets?

The prognosis for pets diagnosed with Valley Fever depends upon the severity of the condition as well as other factors such as your pet's age and overall health.

The Prognosis for Dogs With Valley Fever

When diagnosed and treated early, many dogs recover well from Valley Fever. Dogs diagnosed with Valley Fever after the disease has spread to other parts of the body are more challenging to treat, and in some cases the disease becomes life-threatening.

The Prognosis for Cats With Valley Fever

When caught early, or if your cat is only experiencing localized symptoms of the skin, the prognosis is generally good. If Valley Fever has spread throughout your cat's body the prognosis is poor. While your cat's condition may improve during treatment relapse is very common. It is estimated that about 60-90% of cats recover well from Valley Fever after receiving treatment. 

Preventing Valley Fever in Pets

Because the fungus that causes Valley Fever lives in dry, desert soil, the most common places for infection include Arizona, California, Utah, Texas, and Nevada. Luckily, there are several steps you can take to protect yourself and your pet from contracting Valley Fever.

  • Avoid non-landscaped areas and limit your dog's roaming to well-kept parks.
  • Take walks in paved areas and keep your dog on a leash.
  • If your dog likes digging, avoid desert areas.
  • If your home is in a desert area, keep your pet inside for a reasonable amount of time during the summer.
  • Learn to recognize the signs of Valley Fever and contact your vet immediately if your dog exhibits any symptoms.

Vaccinating Against Valley Fever

There is a vaccine available to immunize your pets against Valley Fever. This will make it much safer for dogs to roam in yards and other dog-safe outdoor areas.

If you live in an area where the condition is common, it’s best to vaccinate your pup on the recommended schedule — likely once or twice a year after the initial dose and booster. There are minimal side effects, and the hope is the vaccine will be approved for manufacture within the year.

If you don’t live in an area with valley fever, it’s important to stay aware of any changes that could happen over time. Climate change increases the infection rate, possibly causing a vaccination need in the future.

Note: The advice provided in this post is intended for informational purposes and does not constitute medical advice regarding pets. For an accurate diagnosis of your pet's condition, please make an appointment with your vet.

If you suspect that your dog may have valley fever, contact our Moreno Valley vets immediately for urgent care. 

New Patients Welcome

Sunnymead Veterinary Clinic always welcomes new patients to our veterinary family! Our vets are passionate about providing quality healthcare to Moreno Valley animals. Contact us today to book an appointment, or visit for walk-in service.

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