Fungal infections in dogs and cats are a health problem whose importance is growing for several reasons. First, they are infections that are impossible to eradicate since they live in their own environment.
On the other hand, they are equally present in humans, but usually only develop in individuals with a growing or deteriorated immune system, so we talk about zoonotic diseases.
Third, they not only affect the skin, but they can affect other organs, such as the respiratory system. Finally, diagnosing, treating, and preventing fungi is an arduous task.
Types of fungal infections in dogs and cats
Fungal infections in dogs and cats not only affect the dermis or epidermal tissue. They can occur in other parts of the body according to the fungal species with which we deal. In many cases, full healing without subsequent relapses is difficult.
The ringworm can be both dogs and cats. The fungus responsible in both cases is Microsporum canis. This fungus is the cause of fungal infections in more than 90% of cases in dogs and cats. In addition, it is the agent that most infects the human being.
Cryptococcosis is a disease caused by the fungi Cryptococcus neoformans and Cryptococcus gattii. It is more frequent and important in cats than in dogs, since it is usually linked to the feline immunodeficiency virus. This fungus affects the eyes, respiratory system, lymph nodes, skin, subcutaneous tissue, and the central nervous system.
Fungal rhinitis – exclusive in dogs – is caused by fungi of the genus Conidiobolus. The only symptom is the intermittent discharge of content through the nostrils. This can be confused with a tumor, so differential diagnosis is necessary.
If it is not diagnosed in time, this fungus can end up destroying the nasal turbinates and penetrating the breasts. This would cause the dog to die by an invasion of different organs, mainly the central nervous system.
Caused by fungi of the genus Aspergillus, this common disease in dogs is still under study. The entrance of the fungus into the body is still unknown, but it is believed that it may be through a wound.
It is usually a chronic disease whose symptoms do not appear until three years after infection. It can infect any organ of the body and even the bones.
The otitis yeast in dogs is curable in 90% of cases. For the remaining 10%, the disease becomes chronic. This otitis is caused by yeasts of the genus Malassezia. It is usually treated with a set of anti-inflammatory, antifungal, and antimicrobial drugs.
Fungi in dogs and cats, how to recognize them?
If you suspect that your pet could have a fungal infection, you should visit a veterinarian as soon as possible. Fungal infections are usually very annoying and sometimes very dangerous for the life of your dog or cat.
There are several ways to diagnose a fungal infection in dogs and cats. It will be the veterinarian who determines which one is the best for your patient.
- Wood lamp: this device uses ultraviolet light to visualize fungi that are on the skin of our pets. To use the Wood lamp correctly, it must be left on for 5 or 10 minutes, so that the wavelength of the light is stabilized. Next, the skin lesions of the animal that we suspect could be fungal infections are exposed to light for another five minutes.
- Direct examination: skin and hair samples can be taken by scraping, or samples from the inside of the ear using a swab and are looked directly at the microscope after staining.
- Culture: samples of the different tissues and fluids are taken, which are suspected of being infected. They are placed in different culture media, and it is expected to see if a fungus develops or not. Then, if the fungus is not visually identifiable, a PCR can be performed to determine the species.
How are fungi transmitted?
As we said, many of these fungal infections can be transmitted to humans, even from animals that have no clinical symptoms. Therefore, it is very important to take our pets to the veterinarian regularly.
Infectious agents can be transmitted through several mechanisms, such as:
- Direct contact with the sick animal without the corresponding prophylaxis.
- Direct ingestion of the pathogen.
- Inhalation, very common in the fungi of birds that usually come from the digestive tract and develop on feces. Contagion is difficult unless we do not keep the cage properly clean.
- Intermediary vectors.