Detecção de Listeria spp de importância em saúde pública em diferentes pontos da obtenção do leite e da elaboração de queijos tipo Minas Frescal / Detection of Listeria spp important in public health from different points of milk obtaining and elaboration of Minas Frescal cheese

Queijos tipo Minas frescal podem veicular microrganismos patogênicos. Este estudo objetivou isolar Listeria spp. e identificar as espécies L. innocua, L. seeligeri, L. ivanovii e L. monocytogenes na obtenção do leite e na elaboração de queijos tipo Minas frescal e detectar a presença de genes de virulência. Foram realizadas coletas em cinco pequenas propriedades rurais produtoras deste tipo de queijo em Jaboticabal-São Paulo. Foram coletadas amostras de suabes de fezes bovinas, amostras de mãos de ordenhador, balde de ordenha, leite, água, superfície de elaboração de queijos, mãos de manipulador do queijo, peneiras, bandejas, fôrmas e escumadeiras. O gênero Listeria spp. teve alta prevalência nas amostras, entretanto, nenhuma das espécies pesquisadas foi identificada. Assim, conclui-se que a presença de Listeria spp. em alta percentagem representa potencial risco de contaminação de Queijos tipo Minas frescal e exige uma vigilância contínua para a presença deste gênero.

Shigatoxigenic and atypical enteropathogenic Escherichia coli in fish for human consumption

ABSTRACT Shigatoxigenic and enteropathogenic Escherichia coli with virulence and multidrug resistance profile were isolated from Nile tilapia. This study finding is of great importance to public health because they help understand this pathogen epidemiology in fish and demonstrate how these animals can transmit E. coli related diseases to humans.

Sorologia e suscetibilidade antimicrobiana em isolados de Escherichia coli de pesque-pagues / Serology and patterns of antimicrobial susceptibility in Escherichia coli isolates from pay-to-fish ponds

Pesquisou-se a ocorrência de Escherichia coli (EPEC, EIEC, O157) em água e peixe (pele, trato digestivo e músculo) de pesque-pagues da microbacia do Córrego Rico, Jaboticabal (SP). Foram isoladas 115 cepas de E. coli, entre as quais 49 (43%) foram sorogrupadas como EPEC. Os sorogrupos mais frequentes foram O125, O126 e O158. Dentre as amostras testadas, 60 (52%) apresentaram resistência simultânea a dois antimicrobianos. A análise de correspondência foi realizada com o intuito de verificar as possíveis correspondências envolvendo o local de isolamento, sorogrupos e multirresistência e, com isso, pôde-se observar que o músculo apresentou menor correspondência com os demais fatores analisados. Porém, o isolamento de sorogrupos EPEC neste estudo representa risco à saúde dos consumidores.(AU)

The occurrence of Escherichia coli (EPEC, EIEC and O157) in water and fish (skin, gut and muscle) in pay-to-fish ponds of the micro bay of Córrego Rico, in Jaboticabal (SP), was assessed. One hundred and fifteen strains of E. coli were isolated, and 49 (43%) were serogrouped as EPEC. The most common serogroups were O125, O126 and O158. Among the tested samples, 60 (52%) showed simultaneous resistance to two antimicrobials. A correspondence analysis was performed to assess possible correlations involving the site of isolation, serogroups and multi-resistance. The results of this analysis showed that the muscle was less correlated with the the other factors. However, the isolation of EPEC serogroups in this study demonstrates a risk to public health.(AU)

Identification and antimicrobial susceptibility patterns of Pasteurella multocida isolated from chickens and japanese quails in Brazil

A study was performed to verify the presence of Pasteurella multocida in eight different poultry groups of 90 birds each. Groups I to IV were chickens (I being > 6 weeks of age with a history of respiratory illness, II > 6 weeks of age and free of respiratory illness, III < 6 weeks of age with respiratory illness and IV being < 6 weeks of age and with no respiratory illness. Groups V to VIII had the matching characteristics of Groups I to V but consisted of Japanese Quails. The P. multocida isolation rate from the groups was as follows; Group I 56/90 (62.3%) Group II 18/90 (20.0%), Group III 12/90 (13.3%), Group IV 3/90 (3.33%), Group V 8/90 (8.88%), Group VI 2/90 (2.22%) Group VII 2/90 (2.22%) and Group VIII 1/90 (1.11%). These isolation rates were not significantly different within the groups of a bird type but the overall chicken isolation rate was significantly higher than the quail isolation rate (p < 0.01). All isolates were examined for their sensitivity to four antimicrobial agents. The results showed only low levels of resistance to the agents tested. The highest level of resistance detected was to cephalothin (5.1% of isolates) followed by amikacin (3.4%).

Phenotypical characterization and adhesin identification in Escherichia coli strains isolated from dogs with urinary tract infections

Pathogenic strains of Escherichia coli are the most common bacteria associated with urinary tract infections in both humans and companion animals. Standard biochemical tests may be useful in demonstrating detailed phenotypical characteristics of these strains. Thirteen strains of E. coli isolated from dogs with UTIs were submitted to biochemical tests, serotyping for O and H antigens and antimicrobial resistance testing. Furthermore, the presence of papC, sfa, and afa genes was evaluated by PCR, and genetic relationships were established using enterobacterial repetitive intergenic consensus PCR (ERIC-PCR). The antimicrobial that showed the highest resistance rate among the isolates was nalidixic acid (76.9%), followed by cephalotin (69.2%), sulfamethoxazole + trimethoprim (61.5%), tetracycline (61.5%), streptomycin (53.8%), ciprofloxacin (53.8%), ampicillin (46.2%), gentamicin (30.8%) and chloramphenicol (23.1%). No isolate was resistant either to meropenem or nitrofurantoin. Among the five clusters that were identified using ERIC-PCR, one cluster (A) had only one strain, which belonged to a serotype with zoonotic potential (O6:H31) and showed the genes papC+, sfa+, afa-. Strains with the genes papC-, sfa+, afa- were found in two other clusters (C and D), whereas all strains in clusters B and E possessed papC-, sfa-, afa- genes. Sucrose and raffinose phenotypic tests showed some ability in discriminating clusters A, B and C from clusters D and E.

Genetic similarity between staphylococcus sp isolated from human and hospital settings, and susceptibility to different antimicrobials / Similaridade genética entre estafilococos isolados de humanos e camas hospitalares e resistência à diferentes antimicrobianos

One hundred and forty-three samples from human hands and hospital beds were collected at a teaching hospital in the city of Ribeirão Preto/SP by swabs, and placed in BHI broth. Following a 24 h incubation period at 37ºC, they were seeded on Petri dishes containing Agar "Staphylococcus Medium 110". Colonies typical of the genus Staphylococcus were collected and stored at 4ºC until tested for catalase, mannitol, hemolysis, DNAse and coagulase. Strains were analyzed by RAPD-PCR to verify their similarity, and tested for sensitivity to ten different antibiotics. From the ninety-two isolated strains, 67 (72,8 percent) were coagulase- negative and 25 (27,2 percent) coagulase-positive. Similarity analysis showed a great heterogeneity among strains, but some presented 100 percent similarity. Resistance to oxacilin was encountered in 39 (42 percent) of the strains. Two coagulase- negative strains were resistant to vancomycin, and eleven (12 percent) were considered multiresistant. Measures such as hand disinfection of the staff and hospital beds and rationalization of antibiotic use could contribute to decrease pathogen transmission and selection pressure, diminishing the frequency and lethality of nosocomial infections.

Foram coletadas 143 amostras de mãos de humanos e camas hospitalares, através de "swabs" no caldo BHI, em um hospital escola da cidade de Ribeirão Preto/SP. As amostras coletadas foram incubadas a 37ºC por 24 horas e após este período as culturas foram semeadas em placas de Petri contendo agar "Staphylococcus Médium 110". As colônias típicas do gênero Staphylococcus foram colhidas e estocados a 4ºC até o momento de elaboração das provas de catalase, manitol, hemólise, DNAse e coagulase. As cepas isoladas foram analisadas através da técnica de RAPD-PCR para verificar o grau de similaridade. A sensibilidade das cepas isoladas foi testada frente a 10 diferentes antibióticos. Das 92 cepas de Staphylococcus sp isoladas, 67 (72,8 por cento) foram identificados como Staphylococcus coagulase-negativas e 25 (27,2 por cento) como Staphylococcus coagulase-positivas. A análise de similaridade mostrou uma grande heterogeneidade entre as cepas, entretanto foram isoladas algumas cepas com 100 por cento de similaridade. Resistência a oxacilina foi encontrada em 39 (42 por cento) cepas. Duas cepas de estafilococos coagulase-negativos mostraram-se resistentes a vancomicina. Onze cepas (12 por cento) de estafilococos foram consideradas multirresistentes. Medidas de desinfecção das mãos de pessoal e dos leitos hospitalares e a racionalização do uso indiscriminado de antibióticos podem contribuir para a queda da transmissão de patógenos e diminuição da pressão de seleção, e conseqüentemente diminuindo a freqüência e letalidade das infecções nosocomiais.

Isolation of Pseudomonas aeruginosa strains from dental office environments and units in Barretos, state of São Paulo, Brazil, and analysis of their susceptibility to antimicrobial drugs / Isolamento de cepas de Pseudomonas aeruginosa provenientes do meio ambiente e de equipos dentarios em clinicas dentarias em Barretos, São Paulo, Brasil; analises da susceptibilidade das cepas a drogas antimicrobianas

A wide variety of opportunistic pathogens has been detected in the tubing supplying water to odontological equipment, in special in the biofilm lining of these tubes. Among these pathogens, Pseudomonas aeruginosa, one of the leading causes of nosocomial infections, is frequently found in water lines supplying dental units. In the present work, 160 samples of water, and 200 fomite samples from forty dental units were collected in the city of Barretos, State of São Paulo, Brazil and evaluated between January and July, 2005. Seventy-six P. aeruginosa strains, isolated from the dental environment (5 strains) and water system (71 strains), were tested for susceptibility to six antimicrobial drugs most frequently used against P. aeruginosa infections. Susceptibility to ciprofloxacin, followed by meropenem was the predominant profile. The need for effective means of reducing the microbial burden within dental unit water lines is emphasized, and the risk of exposure and cross-infection in dental practice, in special when caused by opportunistic pathogens like P. aeruginosa, are highlighted.

Uma ampla variedade de patógenos oportunistas tem sido detectadas nos tubos de alimentação de água dos equipos odontológicos, particularmente no biofilme formado na superfície do tubo. Entre os patógenos oportunistas encontrados nos tubos de água, Pseudomonas aeruginosa é reconhecida como uma das principais causadoras de infecções nosocomiais. Foram coletadas 160 amostras de água e 200 amostras de fomites em quarenta clinicas odontológicas na cidade de Barretos, São Paulo, Brasil, durante o período de Janeiro a Julho de 2005. Setenta e seis cepas de P. aeruginosa, isoladas a partir dos fomites (5 cepas) e das amostras de água (71 cepas), foram analisadas quanto à susceptibilidade à seis drogas antimicrobianas freqüentemente utilizadas para o tratamento de infecções provocadas por P. aeruginosa. As principais suscetibilidades observadas foram para a ciprofloxacina, seguida pelo meropenem. A necessidade de um mecanismo efetivo para reduzir a contaminação bacteriana dentro dos tubos de alimentação de água dos equipos odontológicos foi enfatizada, e o risco da exposição ocupacional e infecção cruzada na prática odontológica, em especial quando causada por patógenos oportunistas como a P. aeruginosa foi realçado.