RESUMO

The antibiotic susceptibility profile and antimicrobial resistance determinants were characterized on Gram-negative bacilli (GNB) isolated from Algerian hospital effluents. Among the 94 isolates, Enterobacteriaceae was the predominant family, with Escherichia coli and Klebsiella pneumoniae being the most isolated species. In non-Enterobacteriaceae, Acinetobacter and Aeromonas were the predominant species followed by Pseudomonas, Comamonas, Pasteurella, and Shewanella spp. The majority of the isolates were multidrug-resistant (MDR) and carried different antimicrobial resistance genes including blaCTX-M, blaTEM, blaSHV, blaOXA-48-like, blaOXA-23, blaOXA-51, qnrB, qnrS, tet(A), tet(B), tet(C), dfrA1, aac(3)-IIc (aacC2), aac(6')-1b, sul1, and sul2. The qacEΔ1-sul1 and intI2 signatures of class 1 and class 2 integrons, respectively, were also detected. Microarray hybridization on MDR E. coli revealed additional resistance genes (aadA1 and aph3strA, tet30, mphA, dfrA12, blacmy2, blaROB1, and cmlA1) and classified the tested strains as commensals, thus highlighting the potential role of humans in antibiotic resistance dissemination. This study is the first report of blaOXA-48-like in Klebsiella oxytoca in Algeria and blaOXA-23 in A. baumannii in Algerian hospital effluents. The presence of these bacteria and resistance genes in hospital effluents represents a serious public health concern since they can be disseminated in the environment and can colonize other hosts.

Assuntos

Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/isolamento & purificação , Esgotos/microbiologia , Argélia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Bactérias Gram-Negativas/classificação , Bactérias Gram-Negativas/genética , Hospitais , Humanos , Klebsiella oxytoca/classificação , Klebsiella oxytoca/efeitos dos fármacos , Klebsiella oxytoca/genética , Klebsiella oxytoca/isolamento & purificação , Testes de Sensibilidade Microbiana , beta-Lactamases/genética , beta-Lactamases/metabolismo

RESUMO

Waterborne pathogens and related diseases are a major public health concern worldwide, not only by the morbidity and mortality that they cause, but by the high cost that represents their prevention and treatment. These diseases are directly related to environmental deterioration and pollution. Despite the continued efforts to maintain water safety, waterborne outbreaks are still reported globally. Proper assessment of pathogens on water and water quality monitoring are key factors for decision-making regarding water distribution systems' infrastructure, the choice of best water treatment and prevention waterborne outbreaks. Powerful, sensitive and reproducible diagnostic tools are developed to monitor pathogen contamination in water and be able to detect not only cultivable pathogens but also to detect the occurrence of viable but non-culturable microorganisms as well as the presence of pathogens on biofilms. Quantitative microbial risk assessment (QMRA) is a helpful tool to evaluate the scenarios for pathogen contamination that involve surveillance, detection methods, analysis and decision-making. This review aims to present a research outlook on waterborne outbreaks that have occurred in recent years. This review also focuses in the main molecular techniques for detection of waterborne pathogens and the use of QMRA approach to protect public health.

RESUMO

Contamination of surface waters in developing countries is a great concern. Treated and untreated wastewaters have been discharged into rivers and streams, leading to possible waterborne infection outbreaks and may represent a significant dissemination mechanism of antibiotic resistance genes. In this study, the water quality of San Pedro River, the main river and pluvial collector of the Aguascalientes State, Mexico was assessed. Thirty sample locations were tested throughout the River. The main physicochemical parameters of water were evaluated. Results showed high levels of fecal pollution as well as inorganic and organic matter abundant enough to support the heterotrophic growth of microorganisms. These results indicate poor water quality in samples from different locations. One hundred and fifty Escherichia coli were collected and screened by PCR for several virulence genes. Isolates were classified as either pathogenic (n = 91) or commensal (n = 59). The disc diffusion method was used to determine antimicrobial susceptibility to 13 antibiotics. Fifty-two percent of the isolates were resistant to at least one antimicrobial agent and 30.6% were multi-resistant. Eighteen E. coli strains were quinolone resistant of which 16 were multi-resistant. Plasmid-mediated quinolone resistance (PMQR) genes were detected in 12 isolates. Mutations at the Ser-83→Leu and/or Asp-87→Asn in the gyrA gene were detected as well as mutations at the Ser-80→Ile in parC. An E. coli microarray (Maxivirulence V 3.1) was used to characterize the virulence and antimicrobial resistance genes profiles of the fluoroquinolone-resistant isolates. Antimicrobial resistance genes such as bla TEM, sulI, sulII, dhfrIX, aph3 (strA), and tet (B) as well as integrons were found in fluoroquinolone (FQ) resistance E. coli strains. The presence of potential pathogenic E. coli and antibiotic resistance in San Pedro River such as FQ resistant E. coli could pose a potential threat to human and animal health.