A novel Sporothrix brasiliensis genomic variant in Midwestern Brazil: evidence for an older and wider sporotrichosis epidemic

Abstract

A novel Sporothrix brasiliensis genomic variant in Midwestern Brazil: evidence for an older and wider sporotrichosis epidemic Sporotrichosis is a subcutaneous infection caused by fungi from the genus Sporothrix. It is transmitted by inoculation of infective particles found in plant-contaminated material or diseased animals, characterizing the classic sapronotic and emerging zoonotic transmission, respectively. Since 1998, southeastern Brazil has experienced a zoonotic sporotrichosis epidemic caused by S. brasiliensis, centered in the state of Rio de Janeiro. Our observation of feline sporotrichosis cases in Brasília (Midwestern Brazil), around 900 km away from Rio de Janeiro, led us to question whether the epidemic caused by S. brasiliensis has spread from the epicenter in Rio de Janeiro, emerged independently in the two locations, or if the disease has been present and unrecognized in Midwestern Brazil. A retrospective analysis of 91 human and 4 animal cases from Brasília, ranging from 1993 to 2018, suggests the occurrence of both sapronotic and zoonotic transmission. Molecular typing of the calmodulin locus identified S. schenckii as the agent in two animals and all seven human patients from which we were able to recover clinical isolates. In two other animals, the disease was caused by S. brasiliensis. Whole-genome sequence typing of seven Sporothrix spp. strains from Brasília and Rio de Janeiro suggests that S. brasiliensis isolates from Brasília are genetically distinct from those obtained at the epicenter of the outbreak in Rio de Janeiro, both in phylogenomic and population genomic analyses. The two S. brasiliensis populations seem to have separated between 2.2 and 3.1 million years ago, indicating independent outbreaks or that the zoonotic S. brasiliensis outbreak might have started earlier and be more widespread in South America than previously recognized.

Exploring genetic diversity, population structure, and phylogeography in Paracoccidioides species using AFLP markers

“…A different perspective was proposed by Eudes Filho et al. ( Eudes Filho et al. 2020 ), which suggests that the S. brasiliensis population in the city of Brasília is extremely unlikely to be derived from the one in Rio de Janeiro, as the latter has a shallow genetic diversity, suggesting an extreme bottleneck.…”

Sporothrix brasiliensis and Feline Sporotrichosis in the Metropolitan Region of Rio de Janeiro, Brazil (1998–2018)

“…However, other studies investigating human, feline, and canine isolates of Sporothrix sp. from Brazil have identified other species, including S. schenckii sensu stricto in a canine case [ 71 ], in feline cases [ 43 , 72 ], and in humans [ 20 , 34 ], as well as S. luriei in a canine case [ 43 ], and S. globosa only in humans [ 73 ]. The description of other Sporothrix species from Brazil, including in dogs and humans from the same geographical region of this study, indicates that they may be circulating among cats in Rio de Janeiro; however, these other Sporothrix species in cats from this region have not yet been confirmed.…”

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

“…Cases of human sporotrichosis have been reported in almost all the 26 Brazilian states, but those directly related to cat transmission due to S. brasiliensis are highly concentered within Southwest and South regions [8], such as Sao Paulo [28], Espirito Santo [29] and Minas Gerais [30]. Recently, a case series of human zoonotic sporotrichosis has been described in Brasilia (Federal District; Midwestern Region) [31]. Only three other publications from the same region of the present study were found, two of them from Pernambuco state [18,32] and a case report of primary pulmonary sporotrichosis in an apparently immunocompetent female patient published by our group [7].…”