In the late 90's there was a change in both the route of transmission and the people at risk for sporotrichosis. This zoonotic cat-man alternative transmission route elicited changes in strategies to control the epidemic. There was a progressive increase in the number of cases involving especially children and the elderly. In addition to becoming hyperendemic, uncommon clinical pictures like immunoreactive clinical presentations or severe systemic cases have emerged. New species were identified and classified through molecular tools using more virulent clinical isolates, like S. brasiliensis, compared to the environmental isolates. Likewise, different species of Sporothrix have been associated with different geographic regions. The serological and molecular techniques are used as an auxiliary tool for the diagnosis and/or for species identification, although the isolation and the identification of Sporothrix spp. in clinical specimen is still the gold standard. Currently sporotrichosis epidemics requires the knowledge of the epidemiological-molecular profile to control the disease and the specific treatment. Itraconazole, potassium iodide, terfinafine, and amphotericin B are the available drugs in Brazil to treat sporotrichosis. The drug of choice, its posology, and treatment duration vary according to the clinical presentation, the Sporothrix species, and host immune status. New treatment choices, including a vaccine, are being developed; nevertheless, more clinical trials are required to confirm its efficacy.

For a long time sporotrichosis has been regarded to have a low incidence in Brazil; however, recent studies demonstrate that not only the number of reported cases but also the incidence of more severe or atypical clinical forms of the disease are increasing. Recent data indicate that these more severe forms occur in about 10% of patients with confi rmed diagnosis. The less frequent forms, mainly osteoarticular sporotrichosis, might be associated both with patient immunodepression and zoonotic transmission of the disease. The extracutaneous form and the atypical forms are a challenge to a newly developed serological test, introduced as an auxiliary tool for the diagnosis of unusual clinical forms of sporotrichosis.

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.

Sporotrichosis is a chronic infectious disease affecting both humans and animals. For many years, this subcutaneous mycosis had been attributed to a single etiological agent; however, it is now known that this taxon consists of a complex of at least four pathogenic species, including Sporothrix schenckii and Sporothrix brasiliensis. Gp70 was previously shown to be an important antigen and adhesin expressed on the fungal cell surface and may have a key role in immunomodulation and host response. The aim of this work was to study the virulence, morphometry, cell surface topology and gp70 expression of clinical isolates of S. brasiliensis compared with two reference strains of S. schenckii. Several clinical isolates related to severe human cases or associated with the Brazilian zoonotic outbreak of sporotrichosis were genotyped and clustered as S. brasiliensis. Interestingly, in a murine subcutaneous model of sporotrichosis, these isolates showed a higher virulence profile compared with S. schenckii. A single S. brasiliensis isolate from an HIV-positive patient not only showed lower virulence but also presented differences in cell morphometry, cell wall topography and abundant gp70 expression compared with the virulent isolates. In contrast, the highly virulent S. brasiliensis isolates showed reduced levels of cell wall gp70. These observations were confirmed by the topographical location of the gp70 antigen using immunoelectromicroscopy in both species. In addition, the gp70 molecule was sequenced and identified using mass spectrometry, and the sequenced peptides were aligned into predicted proteins using Blastp with the S. schenckii and S. brasiliensis genomes.

Although there was no statistical trend between the duration of terbinafine treatment within the groups for complete cure at the end of study, there was a positive correlation between the daily dose of terbinafine (mg x kg(-1)) and complete cure. Terbinafine therapy for 6 weeks could represent an alternative to griseofulvin for the treatment of Microsporum tinea capitis. However, further clinical trials are required in order to optimize the dose regimen to allow higher cure rates to be reached.

Potassium iodide, as a saturated solution, is a valuable drug in the dermatologist's therapeutic arsenal and is useful for the treatment of different diseases due to its immunomodulatory features. However, its prescription has become increasingly less frequent in dermatology practice. Little knowledge about its exact mechanism of action, lack of interest from the pharmaceutical industry, the advent of new drugs, and the toxicity caused by the use of high doses of the drug are some possible explanations for that. Consequently, there are few scientific studies on the pharmacological aspects, dosage and efficacy of this drug. Also, there is no conventional standard on how to manipulate and prescribe the saturated solution of potassium iodide, which leads to unawareness of the exact amount of the salt being delivered in grams to patients. Considering that dosage is directly related to toxicity and the immunomodulatory features of this drug, it is essential to define the amount to be prescribed and to reduce it to a minimum effective dose in order to minimize the risks of intolerance and thus improve treatment adherence. This review is relevant due to the fact that the saturated solution of potassium iodide is often the only therapeutic choice available for the treatment of some infectious, inflammatory and immune-mediated dermatoses, no matter whether the reason is specific indication, failure of a previous therapy or cost-effectiveness.

We performed a serological study with sera from 92 patients with confirmed sporotrichosis registered between 1999 and 2004 in two hospitals in Rio de Janeiro State, Brazil. The clinical presentation of sporotrichosis was distributed as follows: lymphocutaneous, 67%; fixed cutaneous, 23%; disseminated cutaneous, 8%; and extracutaneous, 2%. Sera were assayed by ELISA against a cell wall antigen of Sporothrix schenckii, SsCBF, that we have previously described. The cross-reactivity was determined with 77 heterologous sera. The serological test showed a sensitivity of 90% and a global efficiency of 86%. A group of 55 patients with several clinical presentations of sporotrichosis was clinically and serologically followed-up for at least 6 months. We observed by ELISA data a decrease in the antibody serum titers which correlated with the progress in healing. An HIV-positive patient with meningeal sporotrichosis was serologically followed-up for over 2 years. Serum and cerebrospinal fluid specimens were examined and significant antibodies levels against the antigen SsCBF were detected. Our results strongly suggest that this serological test is valuable for the differential diagnosis and follow-up of all clinical forms of sporotrichosis.

Through statistical analysis, the usual posology was not shown to be superior to the one proposed in this study. Serology for sporotrichosis may be used as a valuable tool in the clinical monitoring of these patients.