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.

Objetivou-se com este estudo investigar se a resistência antimicrobiana (RAM) ou a presença de genes de resistência foi associada com a ocorrência dos genes de virulência, stx1, stx2 e eae e os sorogrupos deEscherichia coli isoladas a partir de vacas-vacas leiteiras. Três genes de virulência e 11 fenótipos RAM foram examinados através de PCR e testes de susceptibilidade aos antimicrobianos. Das 800 amostras colhidas neste estudo, 561 amostras foram isoladas cepas de E. coli, sendo: 90 (16,0%) portadoras de stx1, 97 (17,3%) de stx2 e 45 (8,0%) dos genes eae, separadamente. Trinta e sete (6,6%) isolados foram portadores de stx1 e stx2, 110 (19,6%), foram portadores destx1 e eae e 67 (11,9%) foram portadores de stx2 e eae. O gene de virulência mais comum detectado foi stx1 seguido por stx2. O sorogrupo predominante entre os isolados portadores de stx1 foi O119. Entre as cepas portadoras de stx2, eae e também estirpes com nenhum fator de virulência, o sorogrupo predominante foi O9. O RAM dos isolados, medido fenotipicamente, não foi associado com a presença ou ausência de genes de virulência na população saudável de vaca leiteira-nem a sua ocorrência a qualquer um dos sorogrupos foi associada com genesstx1 e stx2 e eae.

The objectives of this study were to investigate whether antimicrobial resistance (AMR) or the presence of resistance genes was associated with the occurrence of the virulence genes, stx1, stx2 andeae. Three virulence genes and 11 AMR phenotypes were examined using polymerase chain reaction (PCR) and antimicrobial susceptibility tests. From 800 samples collected in this study, 561 samples were isolatesE. coli strains , being: 90 (16.0%) carriers ofstx1, 97 (17.3%) of stx2 and 45 (8.0%) ofeae genes singly. Thirty seven (6.6%) isolates were carriers of stx1 and stx2, 110 (19.6%) were carriers of stx1 and eae and 67 (11.9%) were carriers of stx2 and eae. The most common virulence gene detected was stx1followed bystx2. The findings showed no relationship between presence of virulence factors and antimicrobial resistance. Also was not found relationship between serogroup and virulence factors.

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.

The occurrence of Escherichiacoli (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.

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%).

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.

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%) foram identificados como Staphylococcus coagulase-negativas e 25 (27,2%) como Staphylococcus coagulase-positivas. A análise de similaridade mostrou uma grande heterogeneidade entre as cepas, entretanto foram isoladas algumas cepas com 100% de similaridade. Resistência a oxacilina foi encontrada em 39 (42%) cepas. Duas cepas de estafilococos coagulase-negativos mostraram-se resistentes a vancomicina. Onze cepas (12%) 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.

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%) were coagulase- negative and 25 (27,2%) coagulase-positive. Similarity analysis showed a great heterogeneity among strains, but some presented 100% similarity. Resistance to oxacilin was encountered in 39 (42%) of the strains. Two coagulase- negative strains were resistant to vancomycin, and eleven (12%) 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.

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.

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.