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Introduction:The spread of multidrug-resistant Pseudomonas aeruginosa in Brazilian hospitals has greatly impacted upon the morbidity and mortality of individuals in intensive care units. Given the lack of information regarding the dynamics of multidrug resistance in northern Brazil, we analyzed the clinical and microbiological features of nosocomial infections caused by P. aeruginosa. Methods: Between January 2010 and March 2012, we conducted a retrospective cohort study of P. aeruginosa isolates from 54 patients who were hospitalized in intensive care units. The clinical and epidemiologic variables were analyzed, including the patients' demographic data and comorbidities, and the lengths of the intensive care unit stays, the classification of the infections as nosocomial, the use of invasive procedures, antimicrobial therapy, and the patients' outcomes. We undertook susceptibility tests, molecular detection of the metallo-β-lactamase genes, and genotypic analyses of the isolates using the repetitive element-polymerase chain reaction. Results: Multidrug resistance occurred most frequently among isolates from adults who had been hospitalized for an average of 87.1 days. The use of mechanical ventilation and urinary catheters were risk factors for infection. The four isolates that harbored the blaSPM-1-like gene showed >95% genetic similarity. Conclusions: This study's findings show that P. aeruginosa has a high death rate, and that inadequate treatment and invasive procedures are risk factors for infection. This is the first report describing the detection of the blaSPM-1-like gene in northern Brazil. These results highlight the need for better monitoring and a greater understanding of nosocomial infections and their public health impacts.

Lack of routine surveillance in countries endemic for bovine tuberculosis (tB) and limited laboratory support contributes to the inability to differentiate the Mycobacterium tuberculosis complex species, leading to an underestimated burden of the disease. Here, Whole-Genome Sequencing of Mycobacterium bovis isolated from tissues with TB-like lesions obtained from cattle and buffalos at Marajó Island, Brazil, demonstrates that recent transmission of M. bovis is ongoing at distinct sites. Moreover, the M. bovis epidemiology in this setting is herein found to be dominated by an endemic and unique clade composed of strains evolved from a common ancestor that are now genetically differentiated from other M. bovis clades. Additionally, envisioning a rapid strain differentiation and tracing across multiple settings, 28 globally validated strain-specific SNPs were identified, three of which considered as robust markers for the M. bovis Marajó strain. In conclusion, this study contributes with data regarding the identification of a novel M. bovis phylogenetic clade responsible for ongoing transmission events in both cattle and buffalo species in Brazil, provides a framework to investigate the dissemination of this highly prevalent strain and, holds the potential to inform TB control strategies that may help to prevent the spread of bovine and zoonotic TB. Tuberculosis (TB) is a worldwide important infectious disease in humans and other animals resulting in substantial morbidity and mortality caused by the Mycobacterium tuberculosis Complex (MTBC) pathogens 1,2. Among these, Mycobacterium bovis is the main etiological agent of bovine TB (bTB) in herds and is associated with a decreased livestock productivity due to early disposal of animals of high zootechnical value with subsequent economic impact 3. The impact of bTB and M. bovis is not only restricted to economic aspects of livestock production. Although the economic losses can ascend to, e.g., US$18 200 in a single region as reported for Makurdi in Nigeria