Current Insights into Sporothrix schenckii: From Basic Biology to Virulence Mechanisms

<i>Sporothrix schenckii</i> is a thermodimorphic fungus and one of the main etiological agents of sporotrichosis, a globally distributed subcutaneous mycosis that primarily affects the skin, subcutaneous tissue, and lymphatic system. Historically regarded as the classical species within the <i>Sporothrix</i> pathogenic clade, <i>S. schenckii</i> remains a clinically relevant pathogen and an important biological model for studying fungal dimorphism, virulence, and host-pathogen interactions. Major virulence factors include melanin production, thermotolerance, hydrolytic enzymes, and adhesins, all of which contribute to its survival and dissemination within the host. Clinically, <i>S. schenckii</i> causes a broad spectrum of manifestations ranging from fixed and lymphocutaneous cutaneous forms to disseminated and extracutaneous infections, particularly in immunocompromised individuals. This species exhibits a cosmopolitan distribution with endemic foci in the Americas, Asia, and Africa, and can be transmitted through both sapronotic and zoonotic routes. Diagnosis relies on fungal isolation, molecular identification, and histopathological examination, whereas treatment mainly involves itraconazole, potassium iodide, and amphotericin B for severe cases. This review integrates current knowledge on the biology, virulence, immune response, epidemiology, and treatment of <i>S. schenckii</i>, providing an updated overview of its significance as a medically important fungal pathogen with global relevance.