Allowing pets to roam outside may seem like harmless fun, providing them with exercise, mental stimulation and the opportunity to explore.
Some environments, however, pose hidden dangers that pet owners may not immediately recognize, such as the risk of cryptococcal fungal infections that can infect the lungs, brain and other parts of the body.
Dr. Sara Lawhon, director of the Clinical Microbiology Laboratory for the Veterinary Teaching Hospital of Veterinary Medicine at the Texas A&M School of Veterinary Medicine & Biomedical Sciences, provides insight into this type of fungal infection and why pet owners they must be aware of the potential harm it poses. to their animals – and especially cats.
Susceptibility and signs
Cryptococcus fungal infections are caused by Cryptococcus species of fungi, most commonly Cryptococcus neoformans and Cryptococcus gattii. These fungi are most natural in warm, moist environments, particularly where soil, decaying organic matter (such as wood, leaves, and compost), and bird droppings are present.
“All cats and dogs can develop serious, even life-threatening, cryptococcal infections when they inhale the spores of the fungi, but this type of infection is more commonly associated with cats,” Lawhon said. “Cats of all ages, breeds and sexes can be affected, and infections have been reported in both indoor and outdoor cats.”
While outdoor cats are more likely to be exposed to the fungus, owners or other pets can carry contaminated materials on their shoes or clothing, introducing the fungus to indoor cats.
The most common form of cryptococcal fungal infections in cats affects the nasal cavity and sinuses, with early symptoms including swelling of the nose and face.
“Cats with this form of infection can develop deep, non-healing ulcers of the skin and a chronic nasal discharge that is clear, bloody or full of pus; The inflammation of the nasal tissues can also be in sneezing or difficulty breathe,” Lawhon said. “Although not typically painful, C. neoformans can cause skin lesions, including skin nodules, which are small, raised bumps.”
When cats have nasal cryptococcosis, Lawhon says they can lose weight, not only because of the effects of the fungus on the body, but also because of their decreased sense of smell and interest in food.
Infections that are not addressed promptly can spread to other parts of the body, including the lungs or central nervous system.
“Cats with diseases in their central nervous system can specifically experience blindness, seizures, or changes in their behavior,” Lawhon said. “In some cases, cats go on to develop the disease throughout the rest of the body.”
Proactive vet and owner care
It is important for owners to seek veterinary care as soon as they notice any symptoms in their cats because, as Lawhon said, it can be more difficult to treat patients once the infection spreads to the central nervous system or throughout the body.
“The outlook for patients with nasal cryptococcosis is often better, but usually requires several months of treatment with antifungal drugs,” Lawhon explained. “Veterinarians will diagnose cryptococcal fungal infections based on the patient’s history and clinical signs while confirmation of the diagnosis is made by testing samples from the affected areas or identifying cryptococcal proteins in a blood sample “.
There is currently no vaccine available for cryptococcal fungal infections, making prevention efforts the most important.
“Limiting a cat’s exposure to environments with decaying plant material and bird droppings is likely to reduce the risk of infection,” Lawhon said.
The outdoors can be a source of joy and exploration for pets, as long as owners can ensure the safety and well-being of their pets. By understanding the signs of cryptococcal fungal infections, cat owners, in particular, can act quickly to seek veterinary care and improve the outcome for their beloved pets.
