Sporotrichose

Sporotrichosis is a subacute or chronic subcutaneous mycosis caused by several species of the dimorphic fungus Sporothrix, including S. schenckii, S. globosa, S. mexicana, and S. brasiliensis, that inhabit plant materials and soil ^[1][2][4][3]. The infection is initiated when the fungus is introduced through breaks in the skin, invading deeper layers of subcutaneous tissue and, less frequently, producing extracutaneous disease involving the osteoarticular system, lungs, eyes, or central nervous system ^[1][4][3]. It is regarded as the most important implantation mycosis worldwide, with both sapronotic and zoonotic transmission cycles ^[2].

The classic clinical presentation involves painful cutaneous lesions that develop at the inoculation site and often spread along adjacent lymphatic vessels, producing a characteristic nodular lymphangitis ^[1][3]. Lesions can be unsightly and socially stigmatizing, and infections may be accompanied by systemic involvement in animals, particularly cats infected with S. brasiliensis ^[1][5][3]. Although most human disease remains confined to skin, subcutaneous tissue, and lymphatic vessels, extracutaneous forms such as ocular, osteoarticular, pulmonary, and central nervous system sporotrichosis have been increasingly reported, often from hyperendemic regions ^[4][3].

Sporotrichosis occurs sporadically in tropical and subtropical climates worldwide, with the highest case counts in Central and South America (especially Brazil), the southern United States, Africa, China, and Southeast Asia ^[1]. Localized areas of hyperendemicity have been described in Guatemala, Mexico, Peru, and South Africa, where mining-associated outbreaks linked to contaminated wooden pit props have been documented ^[1]. Since the late 1990s, a large and progressive cat-transmitted epidemic caused by S. brasiliensis has spread from Rio de Janeiro through Brazil and into adjacent South American countries, with molecular epidemiology indicating founder-effect-driven spread, while S. globosa and S. schenckii continue to cause major sapronoses in Asia and the Americas, respectively ^[1][2][3]. Outbreaks have also been associated with flooding events in China, illustrating the influence of environmental exposures on disease occurrence ^[1][2].

Human infection is acquired almost exclusively through traumatic inoculation of the fungus into the skin via contact with contaminated plant debris, soil, or organic matter, which represents the classical sapronotic route ^[1][3]. A second, zoonotic route has become prominent, in which scratches, bites, or contact with exudate from infected cats transmit S. brasiliensis, with feline outbreaks now serving as a major source of human cases ^[1][2][3]. Leisure and occupational activities that handle vegetation or wood—such as floriculture, agriculture, mining, and wood exploitation—are traditionally associated with the sapronotic form ^[3].

A Brazilian guideline for the management of feline sporotrichosis provides information on clinical-epidemiological aspects of this zoonosis and practical guidance helpful for the prevention and control of S. brasiliensis transmission ^[5].

1. 1 World Health Organization. Sporotrichosis [Internet]. cited 4 Sept 2026. Available from: https://www.who.int/news-room/fact-sheets/detail/sporotrichosis
2. 2 Rodrigues AM et al. Current Progress on Epidemiology, Diagnosis, and Treatment of Sporotrichosis and Their Future Trends. J Fungi (Basel). 2022 Jul 26. PMID: 35893145. doi: 10.3390/jof8080776. PubMed: https://pubmed.ncbi.nlm.nih.gov/35893145/
3. 3 Barros MB et al. Sporothrix schenckii and Sporotrichosis. Clin Microbiol Rev. 2011 Oct. PMID: 21976602. doi: 10.1128/CMR.00007-11. PubMed: https://pubmed.ncbi.nlm.nih.gov/21976602/
4. 4 Ramírez-Soto MC et al. Ocular Sporotrichosis. J Fungi (Basel). 2021 Nov 10. PMID: 34829238. doi: 10.3390/jof7110951. PubMed: https://pubmed.ncbi.nlm.nih.gov/34829238/
5. 5 Gremião IDF et al. Guideline for the management of feline sporotrichosis caused by Sporothrix brasiliensis and literature revision. Braz J Microbiol. 2021 Mar. PMID: 32990922. doi: 10.1007/s42770-020-00365-3. PubMed: https://pubmed.ncbi.nlm.nih.gov/32990922/