Types of Fungal Infections in Dogs
While our Thousand Oaks vets typically see fewer fungal infections in dogs than either bacterial or viral infections, fungal infections can be just as serious and treating fungal infections can be challenging.
Your pooch could contract a fungal infection as a result of contact with an infected animal, encountering the fungus in the environment, or due to an overgrowth of the fungi (yeast) which is naturally present in and on your dog's body.
Two categories of fungal infections are commonly seen in dogs, systematic fungal infections (which affect your dog's major body systems) and localized fungal infections (that are generally seen on your dog's skin or external features).
Systematic fungal infections
Systematic fungal infections invade the inner systems of your dog's body, often attacking the dog's lungs, nasal passages, bones or eyes. In the US Aspergillosis, Cryptococcosis, and Blastomycosis are three of the most common systematic fungal infections seen in dogs.
Cryptococcosis
Cryptococcus is a fungus found mainly in areas where large numbers of pigeons or other birds gather. This fungus can be inhaled by your dog, resulting in a lung infection. Cryptococcosis tends to begin in the dog's respiratory tract, but can go on to affect your pet's central nervous system, eyes, and skin. Symptoms of cryptococcosis vary from one dog to another but can include symptoms as wide ranging as skin lesions, lethargy, coughing, nasal discharge, and eye problems, to seizures and other neurologic abnormalities. Oral antifungal medications are typically used to treat dogs suffering from cryptococcosis, however it often needs to be administered for a year or longer. This condition can be difficult to treat and many dog's are unable to recover from this condition.Blastomycosis
Caused by the fungus Blastomyces dermatitidis, blastomycosis most commonly takes the form of a lung infection. This fungus thrives near beaver dams and other areas with moist acidic soil rich in decaying vegetation, where hunting dogs are at the highest risk of inhaling fungal spores. While the infection is contained within the lungs symptoms of blastomycosis include coughing, fever, lethargy, loss of appetite, and weight loss, however if the infection reaches other areas of your dog's body you may notice symptoms such as lameness, blood in urine, eye problems, skin lesions around the toenails, and fever. When diagnosed and treated early oral anti-fungal medications can be a curative treatment.
Aspergillosis
Aspergillus is a species of fungus found in soil all around the world and is responsible for two main types of fungal infections seen in dogs:
Nasal Aspergillosis
- While typically limited to a dog’s nasal passages and sinuses, Nasal Aspergillosis can go on to spread to your pup's bony nasal structures and occasionally the orbit of the eye and skull. Dogs with long narrow heads such as greyhounds and collies seem to be more susceptible to this systematic fungal infection. Symptoms of this kind of fungal infection in dogs include lethargy, bloody nasal discharge or nosebleeds, nasal pain, sneezing, or pain around the nose area. Treatment for Nasal Aspergillosis typically involves infusing the affected dog's nasal passages with a liquid anti-fungal medication. Most dog's recover well following treatment although in some cases a second round of treatment is required.
Disseminated Aspergillosis
- Disseminated Aspergillosis is a more deadly and generalized fungal infection which can affect your dog's bones, muscles or organs. The fungus enters your dog's respiratory tract then makes its way into the bloodstream and throughout the pup's body. Most often seen in German shepherds, this infection is slow to develop, with a range of symptoms that can include back pain, lameness, loss of appetite, muscle wasting, weakness, vomiting, blood in urine, urinary accidents, swollen lymph nodes and even paralysis. Unfortunately the prognosis for dogs with disseminated aspergillosis is poor, although in rare cases treatment can be successful.
Localized (Skin) Fungal Infections in Dogs
It can be difficult for pet parents to recognize that their dog has a localized fungal infection because the itching and scratching associated with these infections are frequently misdiagnosed as dry skin or flea bites. Ringworm and fungal dermatitis are two examples of localized fungal infections that our veterinarians frequently encounter.
Ringworm (Dermatophytes)
Ringworm in dogs is caused by a variety of pathogenic fungi. This skin issue is highly contagious and can spread through direct contact with an infected animal, person, or object (e.g., a couch, comb, bowl, bedding, or carpet). Ringworm symptoms for dogs include hair loss, itching, flaky or crusty skin, and misshapen or brittle nails. Ringworm must be diagnosed and treated early to prevent it from spreading to other household pets or people!
Treatment your dog's ringworm will depend upon the severity of your pup's infection but may include a combination of medicated baths and dips and/or oral antifungal medications. It will also be important to vacuum and disinfect your home frequently in order to help prevent the spread of ringworm to others in your household.
Fungal Dermatitis
Fungal dermatitis is a common inflammatory skin condition caused by excessive yeast growth in your pet's ears, mucocutaneous areas, and skin. Fungal dermatitis can cause severe itching, flaky or crusty skin (especially around your dog's nails, skin folds, armpits, and anal area), and ear infections. Antibiotics may be used in conjunction with topical antifungal treatments such as shampoos or ear ointments.
Treatment of fungal dermatitis may be an ongoing effort. If your dog has a compromised immune system or allergy, fungal dermatitis may be difficult to treat. Some dogs will experience secondary yeast or bacterial skin infections along with severe skin allergies multiple times a year. If this is the case for your pup, your vet will work with you to develop a custom treatment plan to address your dog's health concerns.
Can fungal infections in dogs be considered an emergency?
Fungal infections in dogs can vary in severity, with some cases being mild and easily treatable while others can be more serious and potentially life-threatening. In certain situations, such as when a fungal infection affects vital organs like the lungs or brain, it can indeed be considered an emergency. Symptoms of a severe fungal infection in dogs may include difficulty breathing, neurological issues, persistent vomiting or diarrhea, and sudden changes in behavior.
If you suspect that your dog may have a severe fungal infection, it is crucial to seek immediate veterinary care. Prompt diagnosis and treatment are essential in preventing further complications and improving the chances of recovery.
Are fungal infections in dogs contagious?
Fungal infections in dogs can be contagious to other animals and humans. It is important to practice good hygiene and regularly clean your dog's living areas to prevent the spread of fungal infections. Additionally, if you suspect your dog has a fungal infection, it is best to consult with a veterinarian for proper diagnosis and treatment to prevent further transmission to other pets or people.
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.