The TND-RTM protocol for controlling sporotrichosis in a free-roaming cat colony in southern Brazil

To describe the outcomes of the Trap, Neuter, Diagnosis, Return, Treatment, and Monitoring (TND-RTM) protocol applied to a free-roaming cat colony in a sporotrichosis-endemic area in southern Brazil.

Cats were captured and neutered, clinically assessed for sporotrichosis, and managed according to predefined colony-level therapeutic criteria, whereby the colony was classified as sporotrichosis-positive when at least one individual was affected. All cats within a positive colony were included in antifungal management, including isolation of clinically affected cats and preventive treatment of exposed animals, with continuous visual monitoring.

At baseline, 52.4% of cats (11/21) presented clinical lesions compatible with sporotrichosis. Nineteen cats were captured and clinically evaluated, while two were monitored through visual assessment. Due to demographic changes during follow-up, 11.1% of cats remaining in the colony at 12 months (2/18) still exhibited active lesions. By the end of the 18-month follow-up period, no cats in the colony presented active sporotrichosis lesions (0/18).

The application of the TND-RTM protocol in a single free-roaming cat colony was associated with the resolution of clinical sporotrichosis cases and with improvements in animal welfare at the colony level. This descriptive case study highlights both the potential and the operational challenges of a colony-based approach integrating population management with infectious disease control in endemic urban settings.