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Mastitis is an important disease for the dairy industry worldwide, causing economic losses and reducing milk quality and production. Staphylococcus aureus is a worldwide agent of this intramammary infection, which also causes foodborne diseases. The objective of this study was to determine the frequency of methicillin-susceptible Staphylococcus aureus (MSSA) isolates in milk of mastitis cows in Brazil and to analyze the genetic lineages and the content of antimicrobial resistance genes and virulence factors among these isolates. Fifty-six MSSA isolates were recovered from 1,484 milk samples (positive for the California mastitis test) of 518 cows from 11 different farms in Brazil (representing 51% of total Staph. aureus obtained), and they were further characterized. Methicillin-susceptible Staphylococcus aureus were isolated from 3.7% of California mastitis test-positive tested milk samples and from 6.2% of tested mastitic cows. Methicillin-susceptible Staphylococcus aureus isolates were characterized by spa typing, agr typing, and multilocus sequence typing, and resistance and virulence traits were investigated by PCR. Seven spa types were identified among MSSA (% of isolates): t127 (44.6), t605 (37.5), t002, t1784, t2066 (1.8), and 2 new ones: t10856 (10.7) and t10852 (1.8). Five distinct sequence types (ST) were detected (% of isolates): ST1 (46.4), ST126 (37.5), ST133 (10.7), ST5 (3.6), and a novel ST registered as ST2493 (1.8). Resistances were detected for streptomycin, chloramphenicol, and tetracycline. One strain contained the chloramphenicol resistance gene (fexA; included within transposon Tn558) and 3 strains contained the tetracycline resistance gene [tet(K)]. Methicillin-susceptible Staphylococcus aureus strains were susceptible to most of the antibiotics studied and lacked the virulence genes of Panton-Valentine leukocidin (lukF/S-PV), toxic shock syndrome toxin 1 (tst), exfoliative toxin A (eta), and exfoliative toxin B (etb), as well as the genes of the immune evasion cluster. Methicillin-susceptible Staphylococcus aureus isolates were detected in a relatively low proportion of cows with mastitis (6.2%) and recovered isolates presented high diversity of genetic lineages, with CC1 and CC126 the predominant clonal complexes, and CC133 also being detected. Larger epidemiological studies with molecular characterization of isolates are required to deepen the knowledge on the circulating genetic lineages among the cow population with mastitis.

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Objectives A systematic review and meta-analysis was conducted to determine the cumulative incidences of decannulation and mechanical ventilation weaning in patients with coronavirus disease 2019 (COVID-19) who have undergone a tracheotomy. Weighted average mean times to tracheotomy, to decannulation, and to death were calculated from reported or approximated means. Data Sources PubMed, SCOPUS, CINAHL, and the Cochrane library. Review Methods Studies were screened by 3 investigators independently. Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines were followed. Studies including patients with COVID-19 who underwent a tracheotomy were identified. Studies without reported mechanical ventilation weaning or decannulation were excluded. Data were pooled using a random-effects model. Results After identifying 232 unique studies, 18 articles encompassing outcomes for 3234 patients were ultimately included for meta-analysis, with a weighted mean follow-up time of 28.6 ± 6.2 days after tracheotomy. Meta-analysis revealed that 55.0% of tracheotomized patients were weaned successfully from mechanical ventilation (95% CI, 47.4%-62.2%). Approximately 34.9% of patients were decannulated successfully, with a mean decannulation time of 18.6 ± 5.7 days after tracheotomy. The pooled mortality in tracheotomized patients with COVID-19 was 13.1%, with a mean time of death of 13.0 ± 4.0 days following tracheotomy. Conclusion At the current state of the coronavirus pandemic, over half of patients who have required tracheotomies are being weaned off of mechanical ventilation. While 13.1% patients have died prior to decannulation, over a third of all tracheotomized patients with COVID-19 reported in the literature have undergone successful decannulation.

This is the first report of MRSA carrying mecC in faecal samples of wild small mammals in Spain. These resistant isolates carried genes of the IEC system, unusual in S. aureus from animals. Wild small mammals could be a reservoir of the mecC gene with important implications for public health.