The SARS-CoV-2 pandemic has revived the debate about the routes of virus transmission and their likelihoods. It is of utmost importance to assess the risks of contamination of susceptible people by infectious individuals and to evaluate the level of SARS-CoV-2 and other respiratory viruses transmission in the community. Most countries have imposed non-pharmaceutical measures to contain SARS-CoV-2 transmission, including physical distancing and mask wearing. Here we evaluated the spreading of viruses in open air using harmless Escherichia coli bacteriophages as a surrogate. Phages were sprayed towards Petri dishes seeded with bacteria at different lengths and angles. Our results showed that the transmission rate decreased exponentially with distance. The highest recorded transmission rate was 9 × 10 −6 PFU/plate when phages were sprayed from a 1 m distance, suggesting that the probability of transmission of a single virus at a 1 m distance is 1:100,000.

Introduction: Dermatophytoses are superficial mycoses, and the identification of their etiological agents is routinely performed by culture and microscopic features, which is time-consuming and relies on personnel expertise. Molecular approaches have been developed to provide faster and reliable results; therefore, this study aimed to identify dermatophytes isolated from Alagoas state patients, employing phenotypical and molecular methods. Methodology: Clinical samples for morphological identification were collected from private and public laboratories and cultivated on Sabouraud dextrose agar. DNA extraction was followed by ITS amplicon analysis after restriction enzyme digestion DdeI (ITS-RFLP). Results: Out of fourteen representative strains, ITS-RFLP with DdeI efficiently identified Microsporum canis, Nannizzia gypsea, and Trichophyton rubrum, while species of the complex T. tonsurans/T. mentagrophytes presented the same restriction pattern. After genotyping, 2 T. tonsurans and 1 Microsporum sp. strain were reclassified as T. rubrum. Conclusions: RFLP of ITS-region followed by DdeI digestion produced faster and relatively reliable results than classic methods; however, this method has not been as efficient for closely related dermatophytes cryptic species.

The SARS-CoV-2 pandemic has revived the debate about the routes of virus transmission and their likelihoods. It is of utmost importance to assess the risks of contamination of susceptible people by infectious individuals and to evaluate the level of viral transmission in the community. Most countries have imposed non-pharmaceutical measures to contain SARS-CoV-2 transmission, including social distancing and mask wearing. Here we evaluated the spreading of viruses in open air using harmless Escherichia coli bacteriophages as a surrogate. Phages were sprayed towards Petri dishes seeded with bacteria at different lengths and angles. Median droplets size was 127 µm, similar to those produced by sneeze. Our results showed that the transmission rate decreased exponentially with distance. The highest recorded transmission rate was 9 × 10−6 PFU/plate when phages were sprayed from a 1 m distance, suggesting that the probability of transmission of a single virus at a 1 m distance is 1:100,000. These results agree with the WHO recommendation that face mask protection in an uncrowded well-ventilated space is not required.

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comparison (commercial kit, in-house and by boiling) and PCR to screen 6 clinically important Candida species among the isolates. The correlation between phenotypic and molecular methods was calculated by kappa/K. Only 6 C. parapsilosis (20%) were identified from captive birds' feces among 30 isolates (80% not identified), while pigeons' feces harbored a greater diversity, with the 6 pathogenic species confirmed among 41 isolates: C. albicans (31.70%/13), C. krusei (14.63%/6), C. tropicalis (14.63%/6), C. parapsilosis (17.10%/7), C. glabrata (14.63%/6) and C. guilliermondii (7.31%/3); 100% correlation between tested methods (K = 1) for the first 3 species. Boiling DNA extraction method was fast and efficient to obtain viable DNA from Candida spp. for PCR. Our results indicate that pigeon droppings harbor more potentially pathogenic species than birds in residential captivity, which probably have non-albicans Candida less frequently isolated in infectious processes. The greater availability of nutrients may have contributed to a diversity of Candida spp. in feces from public environments.