Light micrograph of a cats kidney tissue stained with mucicarmine, revealing infection with the fungus Cryptococcus neoformans (pink). C. neoformans is a common yeast fungus found in soil, trees and bird droppings. When cats inhale its spores their lungs can become infected, causing the disease cryptococcosis. Symptoms of cryptococcosis in cats include sneezing, swelling of the nose, nasal polyps and nasal discharge. The infection can spread to the central nervous system in some cases, in which case it can cause seizures, behavioural changes and muscle weakness. This disease can be fatal once it has spread, but treatment is possible via a course of antifungal medication. The disease can not be spread between cats or to humans; infection only occurs from direct inhalation of spores.