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Sporotrichosis is an implantation mycosis caused by the dimorphic fungus Sporothrix and mostly involves cutaneous and subcutaneous tissues and the lymphatic vessels. Among more than 50 different species, only Sporothrix schenckii, Sporothrix globosa and Sporothrix brasiliensis are frequently reported to cause infections in humans. Sporothrix brasiliensis is remarkably virulent and has been spreading rapidly in Brazil and other Latin American countries. In this study, we aimed to determine the genetic relatedness and antifungal susceptibility of Sporothrix strains by analysing 89 isolates from humans and cats in Curitiba, Southern Brazil. Calmodulin sequencing identified 81 S. brasiliensis and seven S. schenckii isolates. Amplified fragment length polymorphism genotyping analysis showed feline and human isolates clustering together. In vitro susceptibility testing with seven antifungals demonstrated a broad activity against all tested S. brasiliensis isolates, with no significant differences in minimal inhibitory concentration (MIC) values between feline and human isolates. Resistance was solely observed in one human isolate against itraconazole and posaconazole, with MICs of ≥16 μg/mL against both antifungals. Whole genome sequencing (WGS) analysis on this isolate and two related susceptible isolates did not reveal any unique substitutions in resistance‐associated genes, including cyp51, hmg and erg6, when compared to two related susceptible isolates. The novel antifungal olorofim exhibited excellent activity against this large isolate collection, with all isolates considered as susceptible. Altogether, we indicate zoonotic transmission based on genotyping and revealed a broad activity of seven common antifungals, including olorofim, against a large S. brasiliensis isolate collection. [ABSTRACT FROM AUTHOR]

The skin of patients with atopic dermatitis (AD) has a greater diversity of mycobiota. An observational, prospective, cross-sectional, analytical, and comparative study was conducted involving 80 patients with AD Group (ADG) and 50 individuals without AD (wADG) in a tertiary hospital in Brazil. Skin scale samples were collected from the frontal, cervical, fossae cubital, and popliteal regions and identified using molecular biology techniques. The results showed that 47.5% of ADG had identified yeasts compared to 0% of wADG (P < .001). The yeasts Rhodotorula mucilaginosa and Candida parapsilosis were the most abundant. The probability of colonization increased with age, showing values of 40% at 60 months and 80% at 220 months (P = .09). The cervical region (12.5%) was colonized to the greatest extent. Our findings revealed that positive mycology was not more probable when the scoring of atopic dermatitis or eczema area and severity index value increased (P = .23 and .53, respectively). The results showed that the sex, age, and different population types directly affected the composition of the mycobiota in the population analyzed. A higher frequency of colonization and greater diversity of yeast species were detected in the cutaneous mycobiota of children with AD., (© The Author(s) 2024. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology.)

Dermatophytosis is a superficial cutaneous infection, most commonly caused by fungal species such as Microsporum canis, Nannizzia gypsea (Microsporum gypseum), and Trichophyton mentagrophytes in dogs and cats. The zoonotic potential of these species is concerning, as companion animals are increasingly close to their owners. Therefore, the objectives of the study were to evaluate the current prevalence of Nannizzia-causing canine and feline dermatophytosis in Curitiba and Metropolitan Region, as well as perform phenotypic and phylogenetic characterizations of these isolates. Thus, 241 skin and fur samples from 163 dogs and 78 cats were analyzed from 2020 to 2021. The samples were obtained from animals of three sources: Veterinary Hospital of the Federal University of Paraná, animal shelters, and private clinics. The diagnosis was performed through phenotypic characterization and sequencing ITS rDNA region. Among 97 positive samples for dermatophytes, Nannizzia was identified in 14 (14.4%) samples, while other dermatophyte genera were found in the remaining 83 (85.6%) samples. Among the canine samples, nine (90%) were N. gypsea, and one (10%) was N. incurvata. Whereas in feline samples, three (75%) were N. gypsea, and one (25%) was N. incurvata. It was concluded that among 97 animals infected with dermatophytes, dogs (24.4%; 10/41) were significantly more affected by Nannizzia than cats (7.1%; 4/56) (P < .05). According to molecular analyses, the ITS rDNA region provided satisfactory results for species-level identification of Nannizzia, confirming the first report of N. incurvata as an etiological agent of canine and feline dermatophytosis in Brazil., (© The Author(s) 2023. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology.)

SARS-CoV-2 environmental monitoring can track the rate of viral contamination and can be used to establish preventive measures. This study aimed to detect by RT-PCR the presence of SARS-CoV-2 from inert surface samples in public health settings with a literature review about surface contamination and its burden on spread virus. Samples were collected from health settings in Curitiba, Brazil, between July and December 2020. A literature review was conducted using PRISMA. A total of 711 environmental surface samples were collected from outpatient areas, dental units, doctors' offices, COVID-19 evaluation areas, and hospital units, of which 35 (4.9%) were positive for SARS-CoV-2 RNA. The frequency of environmental contamination was higher in primary care units than in hospital settings. The virus was detected on doctors' personal items. Remarkably, the previously disinfected dental chair samples tested positive. These findings agree with those of other studies in which SARS-CoV-2 was found on inanimate surfaces. Detection of SARS-CoV-2 RNA on surfaces in public health settings, including those not meant to treat COVID-19, indicates widespread environmental contamination. Therefore, the intensification of disinfection measures for external hospital areas may be important for controlling community COVID-19 dissemination.

Melanized fungi and black yeasts in the family Herpotrichiellaceae (order Chaetothyriales) are important agents of human and animal infectious diseases such as chromoblastomycosis and phaeohyphomycosis. The oligotrophic nature of these fungi enables them to survive in adverse environments where common saprobes are absent. Due to their slow growth, they lose competition with common saprobes, and therefore isolation studies yielded low frequencies of clinically relevant species in environmental habitats from which humans are thought to be infected. This problem can be solved with metagenomic techniques which allow recognition of microorganisms independent from culture. The present study aimed to identify species of the family Herpotrichiellaceae that are known to occur in Brazil by the use of molecular markers to screen public environmental metagenomic datasets from Brazil available in the Sequence Read Archive (SRA). Species characterization was performed with the BLAST comparison of previously described barcodes and padlock probe sequences. A total of 18,329 sequences was collected comprising the genera Cladophialophora, Exophiala, Fonsecaea, Rhinocladiella and Veronaea, with a focus on species related to the chromoblastomycosis. The data obtained in this study demonstrated presence of these opportunists in the investigated datasets. The used techniques contribute to our understanding of environmental occurrence and epidemiology of black fungi.

Knowledge of natural ecology is essential for a better understanding of pathogenicity and opportunism in black yeast-like fungi. Although etiological agents of diseases caused by these fungi are supposed to originate from the environment, their isolation from nature is difficult. This is probably due to their oligotrophic nature, low competitive ability, and, overall, insufficient data on their natural habitat. We obtained environmental samples from mangrove areas where mortalities by lethargic crab disease (LCD) are reported and areas without disease recorded. Isolation of chaetothyrialean black yeasts and relatives was performed using a highly selective protocol. Species-specific primers were used to determine if these isolates represented Exophiala cancerae or Fonsecaea brasiliensis, two proven agents of LCD, in order to test hypotheses about the origin of the disease. Isolates, identified by morphology as Fonsecaea- or Exophiala-like, were tested specific diagnostic markers for the fungi associated with LCD. Although several black fungi were isolated, the main causative agent of the LCD, E. cancerae, was not found. Molecular markers for F. brasiliensis revealed 10 positive bands for isolates from biofilms on mangrove leaves, branches, and aerial roots, of which four were confirmed by ITS sequencing. The absence of E. cancerae in environmental samples suggests that the species is dependent on the crab, as a genuine pathogen, different from F. brasiliensis, which is probably not dependent on the host species, U. cordatus. However, we did not attempt isolation from the marine water, which may represent the pathway of dispersion of the black yeast species between neighbor mangroves.