Assessing the persistence of Sporothrix schenckii and Sporothrix brasiliensis yeasts on hard, non-porous surfaces and the efficacy of disinfectants.

Sporotrichosis is a serious fungal disease of humans and animals worldwide. The ongoing epidemic of cat-transmitted sporotrichosis caused by Sporothrix brasiliensis in South America raises major public health concerns, yet data on environmental persistence and disinfectant efficacy are scarce. Using the quantitative disk carrier method (ASTM 2197), we evaluated persistence and disinfectant susceptibility of Sporothrix schenckii and Sporothrix brasiliensis yeasts on hard, non-porous stainless-steel surfaces. Both species remained viable for at least 6 weeks, supporting the potential for fomite-mediated transmission. We tested seven disinfectant formulations. Sodium hypochlorite (NaOCl) 10,000 ppm (1.0%) and 70% isopropyl alcohol achieved >6 Log10 reduction for both species with 3 min contact time. Intermediate activity was observed with 1,000 ppm (0.1%) NaOCl at 3 min against S. schenckii. For both species, <3 Log10 reduction was observed for 100 ppm (0.01%) NaOCl tested at 3 min contact time, and three veterinary-market products-an accelerated hydrogen peroxide product (Product H2O2) for 1 min, a quaternary ammonium compound (Product QAC), and a potassium peroxymonosulfate product (Product KPS)-tested at 10 and 5 min, respectively. These results demonstrate prolonged surface survival of Sporothrix spp. and identify which disinfectants are effective or ineffective under the tested conditions, concentrations, and contact times. This evidence can guide infection-control practices in clinical and veterinary settings. Notably, 70% isopropyl alcohol is a non-corrosive, less irritating alternative, making it useful for protecting animal patients and veterinary equipment.IMPORTANCECat-transmitted sporotrichosis is an emerging public health concern in South America and is increasingly reported in other continents. Although primarily zoonotic, recent evidence indicates Sporothrix spp. can be transmitted via contaminated surfaces and fomites, raising the risk of indirect transmission and nosocomial spread. Effective surface disinfection is therefore critical-particularly in veterinary clinics-but guidance is limited by a lack of rigorous testing of disinfectant activity against Sporothrix species. Our study fills this gap by assessing the environmental persistence of Sporothrix schenckii and Sporothrix brasiliensis on surfaces and by evaluating the efficacy of seven disinfectant formulations. These results will inform evidence-based infection-control practices to reduce fomite-mediated transmission and protect human and animal health.