Sporotrichosis

Sporotrichosis is a fungal disease caused by organisms of the Sporothrix group, which live naturally in soil, decaying vegetation and on thorny plants. It stands out among feline infections for two reasons: cats develop unusually severe, heavily contaminated lesions, and the disease is genuinely zoonotic — it passes from cats to humans more readily than almost any other feline infection.

Infection usually begins when the fungus is pushed under the skin through a wound — a cat-fight bite, a scratch, or a thorn prick. Outdoor, unneutered male cats that roam and fight are by far the most commonly affected. The first sign is often a small sore that refuses to heal, which then develops into firm nodules and ulcers that ooze pus. Lesions frequently appear on the head, the base of the tail and the limbs, and can slowly spread along the lymphatic channels.

In more serious cases the infection extends beyond the skin to affect the nose, the lungs or internal organs, causing weight loss, breathing difficulty and general illness. Because affected cats carry enormous numbers of the organism in their lesions and even in their claws and mouth, they are highly infectious to other cats and to the people caring for them.

Diagnosis is made by finding the characteristic yeast forms in samples from the lesions, backed up by fungal culture or other laboratory tests. Treatment means a prolonged course of antifungal medication — most often itraconazole — continued for weeks beyond apparent healing to prevent relapse. Cure is achievable but demands real commitment from owners.

Throughout treatment, careful hygiene is essential. Handle affected cats with gloves, wash thoroughly, keep their environment clean, and seek medical advice for any human wound linked to a suspected case. Neutering and reducing free-roaming and fighting are the most effective ways to prevent the disease in the first place.