Valley fever is seen in dogs that spend time in the desert regions of the United States. While healthy adult dogs may experience no symptoms, senior dogs, puppies, and dogs with compromised immune systems may show several serious symptoms. Here, we explain more.
What is valley fever?
Coccidioidomycosis is a condition seen in dogs 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 fungus called Coccidioides immitis that lives in the soil and thrives in particular desert climates. In the U.S., Coccidioides immitis can be found in the low desert regions of Arizona, New Mexico, Texas, and California.
How is valley fever spread?
Valley fever is spread through the inhalation of Coccidioides immitis (fungal) spores. When the spores are inhaled by your dog they grow into structures called 'spherules' within the lungs.
If your dog has a strong and healthy immune system the body will 'wall off' the spherules and your pet will remain asymptomatic (no symptoms of valley fever).
If, however, your dog is very young, old, or has a compromised immune system, the spherules will continue to grow until they eventually burst, releasing hundreds of endospores. These can then spread throughout the lungs and other parts of your pet's body where the cycle will begin again.
Valley fever is not contagious among dogs.
How common is valley fever in dogs?
Central and southern Arizona is believed to have the highest incidence of valley fever in dogs. In certain counties of Arizona, it is estimated that between 6 and 10% of dogs will develop symptoms of valley fever.
What are the early signs of valley fever in dogs?
In the early stages, when the spherules are contained within the lungs, symptoms of valley fever typically include fever, dry cough, decreased appetite, and lethargy.
Once the fungal spores have reached other parts of your dog's body more diverse symptoms may appear such as painful or swollen joints, persistent fever, weight loss, eye inflammation, and blindness. In some very rare cases, if the fungus reaches the brain, valley fever can result in 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.
Is valley fever curable in dogs?
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.
What is the treatment for valley fever in dogs?
Antifungal medications are the primary treatment for valley fever in dogs. How long your dog will need to take these medications will depend upon the severity of your pup's condition.
In most cases, antifungal medications will need to be administered for 6-12 months, with an improvement in symptoms often being seen within a week or two. When valley fever has spread to other parts of the body, your dog may need to continue taking antifungal medications for life.
Some of the most common antifungal medications used to treat valley fever in dogs include ketoconazole (Nizoral®), itraconazole (Itrafungol® and Sporanox®), and fluconazole (Diflucan®).