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Plague is a flea-borne zoonosis that affects a wide range of mammals and still causes outbreaks in human populations yearly across several countries. While crucial for proper treatment, early diagnosis is still a major challenge in low- and middle-income countries due to poor access to laboratory infrastructure in rural areas. To tackle this issue, we developed and evaluated a new F1-based rapid diagnostic test (RDT) as an alternative method for plague diagnosis in humans and other mammals in the field. In this study, 187 serum samples from humans, dogs, rodents and rabbits were retrospectively assessed using the Plague RDT method. To calculate its performance rates, results were confronted to those obtained by hemagglutination (HA) and ELISA, considered as the reference standards. Remarkably, the results from RDT were in full agreement with those from the ELISA and HA assays, resulting in 100% (CI 95% = 95.5-100%) of sensitivity and 100% (CI 95% = 96.6-100%) of specificity. Accordingly, the Cohen’s Kappa test coefficient was 1.00 (almost perfect agreement). Moreover, the RDT showed no cross-reaction when tested with sera from individuals positive to other pathogens, such as Yersinia pseudotuberculosis, Yersinia enterocolitica, Anaplasma platys, Erliquia canis and Leishmania infantum. Although preliminary, this study brings consistent proof-of-concept results with high performance rates of the Plague RDT when compared to other methods well-established in the plague routine serodiagnosis. Although further human and animal population-based studies will be necessary to validate these findings, the data presented here show that the Plague RDT is highly sensitive and specific, polyvalent to several mammal species and simple to use in field surveillance or point-of-care situations with instant results.

Justification and Objectives: Circulating blood is sterile and the presence of microorganisms can be of clinical interest, especially in the hospital environment, being able to cause infectious processes and substantially increase morbidity and mortality. The objective of this work was to characterize the isolates of the genus Staphylococcus spp. from bloodstream infections as to the production of bacterial biofilm and resistance to the main antimicrobials used in clinical practice. Methods: Blood cultures were collected with an indication of positivity for bacterial growth from multiple sectors of the study hospital, which were subsequently processed to identify the bacterial genus through the use of phenotypic tests for Gram positive bacteria. The verification of the resistance profile was performed following the Kirby-Bauer disk diffusion. The identification of the production and quantification of the bacterial biofilm occurred following the protocol described by O’toole (2010). Results: The most frequent clinical isolate was Coagulase negative Staphylococci 38 (54.29%), followed by Staphylococcus aureus 32 (45.71%). Resistance to erythromycin, norfloxacin, levofloxacin and azithromycin was observed in most isolates (70%). Regarding methicillin, more MRSA (59.38%) than MR-CONS (47.37%) were isolated. The ICU was the place where the formation of the biofilm showed indicative data of greater adherence, which was associated with MRSA strains. Conclusion: The bacterial isolates associated with bloodstream infections showed high resistance to antimicrobials. The presence of MRSA and MR-CONS with strong and/or moderate biofilm production capacity represents a greater risk to the health of patients affected by infections caused by these agents.

OBJECTIVE: to verify the presence, resistance profile, as well as bacterial biofilm production of non-fermenting Gram-negative Bacillus isolates from tracheal secretion, blood culture and surfaces of an Intensive Care Unit. METHODS: MacConkey Agar, TSI and oxidase test were used for bacterial identification. Antimicrobial resistance occurred by the Kirby-Bauer disk diffusion method and the presence of bacterial biofilm was verified by Quantitative Microtiter Dish Biofilm Formation assay. RESULTS : of 30 isolates of negative Gram, seven were NFGNB. Four of the genus Acinetobacter sp ., two of the genus Pseudomonas sp ., and one of the genus Burkholderia sp . was identified. The results showed moderately and strongly biofilm producing isolates. CONCLUSION: the bacteria found showed resistance the antibiotics tested associated with biofilm production biofilm. Identification these pathogens can greatly contribute to more effective hospital antibiotic therapy. Keywords: Biofilm; Microbial Drug Resistance; Intensive Care Unit, Bacteria.

Objective To describe the molecular mechanisms of polymyxins resistance in five Enterobacteriaceae clinical isolates from a tertiary hospital of Recife, Brazil. Methods The species identification and the susceptibility to antimicrobials were firstly performed by automatized methods and polymyxin resistance was confirmed by broth microdilution methods. The genetic basis of resistance was characterized with WGS analyses to study their resistome, plasmidome and mobilome, by BLAST searches on reference databases. Results Five (5%) Enterobacteriaceae isolates, comprising Escherichia coli (n = 2), Klebsiella pneumoniae (n = 2) and Citrobacter freundii (n = 1) species, exhibited polymyxin resistance. The mcr-1.1 gene was found in identical IncX4-plasmids harbored by both K. pneumoniae C119 (PolB MIC = 512 mg/L) and E. coli C153 (PolB MIC = 8 mg/L). The remaining E. coli strain C027 harbored the mcr-5.1 gene on an undefined Inc-plasmid (PolB MIC 256 mg/L). Some amino acid substitutions in PmrA (S29G, G144S), PmrB (S202P; D283G, W350*, Y258N) and PhoP (I44L) was detected among the E. coli clinical isolates, however they were also found in colistin-susceptible strains and predicted as neutral alterations. The mgrB of the ST54 KPC-2-producing K. pneumoniae C151 (PolB MIC = 32 g/mL) was interrupted at 69 nt by the IS903 element. The ST117 C. freundii C156 (PolB MIC = 256 mg/L) showed the A91T substitution on HAMP domain of the histidine kinase sensor CrrB, predicted as deleterious and deemed the remarkable determinant to polymyxins resistance in this strain. Conclusions Diverse mechanisms of polymyxins resistance were identified among clinical Enterobacteriaceae from a tertiary hospital of Recife, Brazil, such as plasmid-mediated MCR-1 and MCR-5; IS903-interruption of mgrB and mutation in CrrAB regulatory system. These findings highlight the involvement of the identified plasmids on mcr dissemination among Enterobacteriaceae; warn about co-selection of the polymyxin-resistant and KPC-producer K. pneumoniae ΔmgrB lineage by carbapenems usage; and demonstrate potential role of CrrAB on emerging of polymyxin resistance among Enterobacteriaceae, besides Klebsiella species.

Acinetobacter baumannii is an opportunistic bacterial pathogen infecting immunocompromised patients and has gained attention worldwide due to its increased antimicrobial resistance. Here, we report a comparative whole-genome sequencing and analysis coupled with an assessment of antibiotic resistance of 46 Acinetobacter strains (45 A. baumannii plus one Acinetobacter nosocomialis) originated from five hospitals from the city of Recife, Brazil, between 2010 and 2014. An average of 3,809 genes were identified per genome, although only 2,006 genes were single copy orthologs or core genes conserved across all sequenced strains, with an average of 42 new genes found per strain. We evaluated genetic distance through a phylogenetic analysis and MLST as well as the presence of antibiotic resistance genes, virulence markers and mobile genetic elements (MGE). The phylogenetic analysis recovered distinct monophyletic A. baumannii groups corresponding to five known (ST1, ST15, ST25, ST79, and ST113) and one novel ST (ST881, related to ST1). A large number of ST specific genes were found, with the ST79 strains having the largest number of genes in common that were missing from the other STs. Multiple genes associated with resistance to β-lactams, aminoglycosides and other antibiotics were found. Some of those were clearly mapped to defined MGEs and an analysis of those revealed known elements as well as a novel Tn7-Tn3 transposon with a clear ST specific distribution. An association of selected resistance/virulence markers with specific STs was indeed observed, as well as the recent spread of the OXA-253 carbapenemase encoding gene. Virulence genes associated with the synthesis of the capsular antigens were noticeably more variable in the ST113 and ST79 strains. Indeed, several resistance and virulence genes were common to the ST79 and ST113 strains only, despite a greater genetic distance between them, suggesting common means of genetic exchange. Our comparative analysis reveals the spread of multiple STs and the genomic plasticity of A. baumannii from different hospitals in a single metropolitan area. It also highlights differences in the spread of resistance markers and other MGEs between the investigated STs, impacting on the monitoring and treatment of Acinetobacter in the ongoing and future outbreaks.

In this study, Bacillus cereus was cultivated in a mineral medium composed of 2% frying oil and 0.12% peptone to produce a biosurfactant. The production was scaled up from flasks to 1.2-, 3.0- and 50-L bioreactors, where surface tension achieved 28.7, 27.5 and 32 mN/m and biosurfactant concentration 4.3, 4.6 and 4.7 g/L, respectively. The biosurfactant was characterized as anionic, while nuclear magnetic resonance, thin-layer chromatography and gas chromatography analyses revealed its lipopeptide nature. Toxicity tests showed survival rates of the fish Poecilia vivipara and the bivalve Anomalocardia brasiliana higher than 90% and 55%, respectively, thus suggesting the use of this biosurfactant in marine environment depollution. Moreover, the biosurfactant stimulated the growth of autochthonous microorganisms independently of the presence of motor oil in bioassays performed in seawater. These results demonstrate that the biosurfactant is biocompatible and has potential for industrial-scale production and application to bioremediation of oil spills-polluted marine environment.

Acinetobacter baumannii is one of the most frequent Gram-negative opportunistic pathogens associated with hospital-acquired infection worldwide. We briefly describe A. baumannii isolates that were recovered from surrounding ICU bed surfaces, exhibiting multidrug resistance phenotype and belonging to some widely spread clonal complexes of clinical A. baumannii isolates. Keywords: Acinetobacter baumannii, Hospital environment, ICU surface

Objective : to perform a carbapenemase screening in the main Gram negative microorganisms isolated from active cultures surveillance in patients of the Intensive Care Unit (ICU) of an emergency hospital in the city of Caruaru, Pernambuco, Brazil. Method : this is a descriptive, cross-sectional study where the samples obtained were collected following the principles described by the Ministry of Health for cultures surveillance. Results : the identification of patients colonized by carbapenemase through cultures surveillance showed a positivity of 88% of the total samples collected, with Klebsiella pneumoniae being the most frequent (31.81%). Conclusion : in addition to allowing the early identification of asymptomatic colonizers, cultures surveillance provide microbiological information on the epidemiological profile of the health unit. The high carbapenemase detection rate in this study shows the importance of performing this technique as a reinforcement measure aimed at patient safety.

Justificativa e Objetivos: Este estudo teve como objetivo avaliar a presença e resistência de Staphylococcus aureus e estafilococos coagulase-negativos resistentes à oxacilina isolados em superfícies e hemoculturas em uma Unidade de Terapia Intensiva de um hospital de emergência na cidade de Caruaru, Pernambuco, Brasil. Métodos: Trata-se de um estudo descritivo, do tipo transversal, sendo as coletas realizadas a partir das superfícies dos leitos de uma Unidade de Terapia Intensiva (UTI). Paralelamente, amostras de hemoculturas dos respectivos pacientes também foram obtidas. As amostras foram coletadas por amostragem de conveniência e a identificação dos microrganismos isolados se deu através de espectrometria de massas. Resultados: Observou-se uma prevalência maior de bactérias do grupo dos Staphylococcus coagulase negativo-SCN (76,92%) em relação à espécie de Staphylococcus aureus (23,07%). Dentre os microrganismos identificados como resistentes à oxacilina, 12,5% das espécies apresentaram semelhança nas amostras de superfície do leito e hemocultura do mesmo paciente. Conclusões: As bactérias resistentes identificadas reforçam a importância de enfatizar as medidas gerais de higienização do ambiente no que se refere a segurança do paciente nos serviços de saúde. DESCRITORES: Infecção Hospitalar. Contaminação de Equipamentos. Unidades de Terapia Intensiva. Infecções Estafilocócicas.

Resumo Objetivo Avaliar a resistência microbiana a medicamentos de bactérias isoladas de equipamentos próximos aos pacientes da Unidade de Terapia Intensiva. Métodos Trata-se de um estudo transversal. As amostras foram coletadas com swabs umedecidos em Trypticase Soy Broth, semeados posteriormente em Ágar Sangue de Carneiro e MacConkey. A identificação fenotípica ocorreu com base na morfologia das cepas e resultados bioquímicos. A análise da resistência aos medicamentos foi baseada no método de disco-difusão de Kirby-Bauer. Resultados Apresentaram-se contaminados 94,4% dos equipamentos analisados. Os microrganismos isolados mais frequentes foram: Acinetobacter sp., Staphylococcus aureus e Pseudomonas sp. Cerca de 75% de Acinetobacter sp. apresentaram resistência à piperacilina associada a tazobactam, meropenem e levofloxacina. Da mesma forma, 36,3% de S. aureus apresentaram-se resistentes à oxacilina e 10% dos isolados de Pseudomonas sp. foram resistentes aos medicamentos testados. Conclusão A maioria dos isolados apresentaram elevadas taxas de resistência microbiana aos medicamentos.