The threat of emerging and re-emerging pathogenic Sporothrix species

Abstract

Sporotrichosis is a neglected subcutaneous mycosis of humans and animals acquired by traumatic inoculation of soil and plant material (classical route) contaminated with infectious propagules of the pathogen or being bitten/scratched by infected cats (alternative route). Within a genus composed of 53 species displaying an essentially environmental core, there are only a few members which have considerable impacts on human or animal health. Infections are typically caused by S. brasiliensis, S. schenckii or S. globosa. Rare mammal pathogens include members of the S. pallida and S. stenocereus complexes. To illustrate the tremendous impact of emerging zoonotic sporotrichosis on public health, we discuss the main features of the expanding epidemics driven by S. brasiliensis in cats and humans. The cat entry in the transmission chain of sporotrichosis, causing epizooties (cat-cat) or zoonosis (cat-human), has contributed to the definition of new paradigms in Sporothrix transmission, reaching epidemic levels, making the disease a serious public health problem. Indeed, S. brasiliensis infection in humans and animals is likely to become even more important in the future, with projections of its expansion in biogeographic domains and host range, as well as greater virulence in mammals. Therefore, lessons from a long-standing outbreak in the state of Rio de Janeiro about the source and distribution of the etiological agents among outbreak areas can be used to create better control and prevention plans and increase awareness of sporotrichosis as a serious emerging zoonotic disease. Keywords Sporothrix Á Sporotrichosis Á Emerging zoonoses Á Control and prevention Á Preparedness and biodefense Á Pathogenicity Á Virulence Á Sporothrix brasiliensis Á Neglected tropical diseases The story behind the Sporothrix species pathogenic to mammals Sporotrichosis is a fungal disease caused by the infection of Sporothrix spp. It usually affects the skin Handling editor: Ferry Hagen.

The spread of cat-transmitted sporotrichosis due to Sporothrix brasiliensis in Brazil towards the Northeast region

“…All the strains (except the strain obtained from patient 144) recovered from mycological cultures belong to this species, following the same trend of studies regarding zoonotic sporotrichosis performed in Brazil. It is important to note that S. brasiliensis was restricted to the South and Southeast of Brazil until mid-2010 [23]. Other Sporothrix spp., mainly S. schenckii sensu stricto, have been less related to transmission by cats in a few countries, including the United States, India, Malaysia, Argentina, Mexico, and Panama [17].…”

A One Health Approach to Combatting Sporothrix brasiliensis: Narrative Review of an Emerging Zoonotic Fungal Pathogen in South America

“…Unlike other dimorphic fungi, which only cause infection when transmitted by the mold form, S. brasiliensis is unique in its ability to be transmitted in the yeast phase as well, a key factor in facilitating transmission between mammals [7,9]. Notably, groups at high risk for CTS include those who have frequent contact with cats, such as veterinarians, veterinary technicians, animal caretakers, and cat owners [3].…”

“…do not cause human or animal infections. However, the "pathogenic clade" of the genus Sporothrix, which includes S. schenckii, S. globosa, and S. brasiliensis, infects mammals [1][2][3]. Sapronotic transmission (from the environment) was the most common source of human sporotrichosis historically, but zoonotic infections have become increasingly common with the emergence of S. brasiliensis.…”

Molecular‐based assessment of diversity and population structure of Sporothrix spp. clinical isolates from Espírito Santo‐Brazil

“…3,[5][6][7] Less frequent sporotrichosis agents include members of the environmental clade such as those embedded in the S pallida and S stenoceras complexes. 8 Typically, there are two important routes of Sporothrix transmission to humans: (a) the classic transmission, known as the sapronotic route, involving direct contact with soil and decomposing organic matter; and (b) the zoonotic transmission, in which felines actively participate in the transmission of the disease. 9 In this context, S brasiliensis, S schenckii s. str.…”

“…12 In Brazil, except for the Roraima state, isolate cases and small outbreaks have been sporadically reported. 8 However, it is noteworthy that the country's southeast region, especially Rio de Janeiro state, has suffered a large and important epidemic due to zoonotic transmission, with cats being the primary disease vector. In this region, S brasiliensis is the principal aetiologic agent reported.…”