Detección de serovares de Salmonella en terneros de crianza artificial de la región lechera Mar y Sierras, Argentina / Detection of serovars of Salmonella in artificially reared calves in Mar y Sierras Dairy Basin, Argentina

La salmonelosis es una de las enfermedades bacterianas que afectan el tracto digestivo de los terneros y provocan en ellos diarrea. Con el objetivo de estudiar la prevalencia de los distintos serovares de Salmonella en terneros de crianza artificial y determinar la asociación con signos diarreicos, se realizó un estudio epidemiológico con diseno transversal en la región lechera Mar y Sierras, ubicada en la Provincia de Buenos Aires (Argentina). Mediante hisopado de mucosa rectal, se muestrearon 726 terneros en período de crianza distribuidos en 50 establecimientos lecheros de dicha zona, se incluyeron animales con signos diarreicos y sin estos. Los aislamientos identificados como Salmonella spp. fueron tipificados utilizando antisueros poli- y monovalentes dirigidos contra antígenos somáticos, flagelares y capsulares (Vi). Salmonella spp. se detectó en el 36% de los establecimientos y los serovares hallados fueron S. Mbandaka, S. Anatum, S. Typhimurium, S. Dublin, S. Montevideo, S. Meleagridis, S. Newport, S. Seftemberg, S. subesp.16,7:z1, S. Infantis y S. Give. El 5,5% de los terneros fueron positivos y aquellos terneros con signología diarreica presentaron 5,9 veces más probabilidad de estar infectados con Salmonella spp. que aquellos que no tuvieron signos. La edad de los terneros positivos osciló desde un día hasta 53 días de vida; la mayor frecuencia se detectó al segundo día de nacidos. Se concluye que 11 serovares de Salmonella están presentes en más de un tercio de los establecimientos lecheros de la región lechera Mar y Sierras y que estos serovares mostraron estar asociados a la existencia de signos diarreicos en los terneros, sobre todo a la presencia de moco en las heces. La prevalencia de Salmonella fue mayor en terneros de menos de 21 días de vida.

Salmonellosis in calves is a bacterial disease that affects their digestive tract causing diarrhea. A cross-sectional epidemiological study was carried out with the aim of studying the prevalence of various serovars of Salmonella in calves and their relationship with diarrhea signs. The study was conducted in Mar and Sierras Dairy Basin located in Buenos Aires province, Argentina. Seven hundred and twenty six calves both with diarrhea signs or not were sampled by rectal mucosa swab in 50 dairy farms during the rearing period. Isolates identified as Salmonella spp. were classified using polyvalent and monovalent antisera against somatic, flagellar and capsule antigens (Vi). Salmonella spp. was found in 36% of the farms and serotypes were: S. Mbandaka, S. Anatum, S. Typhimurium, S. Dublin, S. Montevideo, S. Meleagridis, S. Newport, S. Seftemberg, S. subesp. 16,7:z1, S. Infantis, S. Give. A percentage of 5.5% calves was positive and calves showing diarrheal signs were 5.9 times more likely to be infected with Salmonella spp. than those having no signs. The age of positive calves ranged from the first day of life to 53; the second day being the most frequent time. In conclusion, 11 Salmonella serovars were detected in one out of 3 dairy farms in Mar and Sierras Dairy Basin, and not only were these serovars associated with diarrhea signs including the presence of mucus in feces, but they were also more prevalent among calves aged up to 21 days.

Occurrence of Salmonella sp. in poultry carcasses evaluated from the retail trade between 2007 and 2013 in Paraná state, Brazil / Ocorrência de Salmonella sp. em carcaças de frango avaliadas a partir do comércio varejista entre 2007 e 2013 no estado do Paraná, Brasil

Poultry meat is often involved as a vehicle for microorganisms that cause food-borne diseases. Salmonella sp. is a major pathogen involved in outbreaks around the world. Based on its importance, the objective of this study was to determine the occurrence of Salmonella sp. in frozen and chilled poultry carcasses slaughtered and marketed in the western region of Paraná state, Brazil. A total of 340 samples were collected between January 2007 and April 2013, with 66 (19.41%) carcasses positive for Salmonella sp. It can be concluded from the results obtained that the occurrence of Salmonella sp. in poultry carcasses remains high, even though it is a product marketed refrigerated or frozen, methods considered appropriate for food preservation. A lower occurrence result was expected due to the 14-year implementation of the national pathogen reduction program established by the Ministry of Agriculture, Livestock and Supply aimed at a gradual reduction in the occurrence of Salmonella sp. in these products through constant monitoring of carcasses immediately after slaughter.(AU)

A carne de aves é um alimento que frequentemente encontra-se envolvido como veículo de micro-organismos causadores de enfermidades, sendo Salmonella sp. um desses agentes comumente envolvidos nessas enfermidades em todo o mundo. Com isso, o objetivo deste estudo foi determinar a ocorrência de Salmonella sp. em carcaças de frango congeladas e refrigeradas, abatidas e comercializadas na região oeste do estado do Paraná. Um total de 340 amostras foram coletadas entre janeiro de 2007 e abril de 2013. Das amostras analisadas, 66 (19,41%) das carcaças foram positivas para Salmonella sp. De acordo com os resultados obtidos pode-se concluir que a ocorrência de Salmonella sp. em carcaças de frangos permanece alta, mesmo sendo produtos comercializados refrigerados ou congelados, métodos considerados adequados para conservação de alimentos. Um resultado de menor ocorrência era esperado devido à implementação de 14 anos do Programa Nacional de Redução de Patógenos estabelecido pelo Ministério da Agricultura, Pecuária e Abastecimento visando uma redução gradual na ocorrência de Salmonella sp. nestes produtos através de monitoramento constante de carcaças imediatamente após o abate.(AU)

Survey on pathogenic Escherichia coli and Salmonella spp. in captive cockatiels (Nymphicus hollandicus)

Abstract We surveyed healthy captive cockatiels (Nymphicus hollandicus) for Escherichia coli and Salmonella spp. Cloacal swabs were collected from 94 cockatiels kept in commercial breeders, private residencies and pet shops in the cities of São Paulo/SP and Niterói/RJ (Brazil). Three strains of E. coli from each individual were tested for the presence of ExPEC-, APEC- and DEC-related genes. We evaluated the blaTEM, blaSHV, blaOXA, blaCMY, blaCTX-M, tetA, tetB, aadA, aphA, strAB, sul1, sul2, sul3, qnrA, qnrD, qnrB, qnrS, oqxAB, aac (6)′-Ib-cr, qepA resistance genes and markers for plasmid incompatibility groups. Salmonella spp. was not detected. E. coli was isolated in 10% of the animals (9/94). Four APEC genes (ironN, ompT, iss and hlyF) were detected in two strains (2/27-7%), and iss (1/27-4%) in one isolate. The highest resistance rates were observed with amoxicillin (22/27-82%), ampicillin (21/27-79%), streptomycin (18/27-67%), tetracycline (11/27-41%). Multiresistance was verified in 59% (16/27) of the isolates. We detected strAB, bla TEM, tetA, tetB, aadA, aphaA, sul1, sul2, sul3 resistance genes and plasmid Inc groups in 20 (74%) of the strains. E. coli isolated from these cockatiels are of epidemiological importance, since these pets could transmit pathogenic and multiresistant microorganisms to humans and other animals.

Prevalence and identification of Salmonella spp. in water buffaloes from São Paulo State, Brazil / Prevalência e identificação de Salmonella spp. em búfalos do Estado de São Paulo, Brasil

O objetivo do estudo foi investigar a prevalência de Salmonella spp. em amostras de fezes de búfalos do estado de São Paulo, Brasil, e identificar os sorotipos isolados. Foram examinadas 116 amostras de suabes retais de búfalos das raças Jafarabadi e Murrah, coletadas em triplicata, em seis propriedades rurais localizadas nas regiões Central, Centro-Oeste e Nordeste do estado de São Paulo, Brasil. Para avaliar a presença de Salmonella spp., foram utilizados três diferentes caldos de enriquecimento (caldo selenito cistina, caldo tetrationado Muller-Kauffmann e caldo Rappaport-Vassiliadis) e dois diferentes meios de cultura (ágar verde brilhante modificado e ágar XLT4). Das 116 amostras de suabes retais examinadas, oito amostras (6,90%; 8/116) foram positivas para Salmonella spp., incluindo quatro sorotipos: S. Panama (50%; 4/8), S. Agona (25%; 2/8) , S. Newport (12,5%; 1/8) e S. Saintpaul (12,5%; 1/8), todos isolados de búfalos sem sinais clínicos de salmonelose, indicando a importância dos animais assintomáticos como fonte de infecção para outros animais e seres humanos. Das seis propriedades rurais avaliadas, apenas em duas fazendas (33,3%; 2/6) não foi detectada Salmonella spp. O uso de mais de um caldo de enriquecimento seletivo e de mais de um meio de cultura é indicado para o isolamento de Salmonella.(AU)

Perfil de resistencia a antibióticos de serotipos de Salmonella spp. aislados de carne de res molida en la Ciudad de México / Antibiotic of resistence profile of Salmonella spp. serotypes isolated from retail beef in Mexico City

Resumen: Objetivo: Determinar el serotipo y perfil de resistencia a antibióticos de cepas de Salmonella spp. presentes en la carne de res que se expende en la capital mexicana. Material y métodos: Se analizaron 100 muestras de carne molida. Se aisló el patógeno por métodos convencionales y se confirmó por PCR (gen InvA, 284 pb). El perfil de resistencia a antibióticos se determinó por el método de Kirby-Bauer y la serotipificación por el esquema de Kauffman-White. Resultados: Se detectaron los serotipos Lomita (6), Derby (4), Senftenberg (2), Javiana y Cannsttat (1). Se observó alta resistencia a ampicilina (18/19), carbenicilina (16/19), tetraciclina (13/19) y trimetoprim-sulfametoxasol (13/19). Cinco cepas fueron no tipificables y 14 mostraron multirresistencia. Conclusiones: La carne de res que se vende en el principal centro de consumo del país está contaminada con serotipos de Salmonella spp. relevantes para la salud pública. Una importante proporción de éstos es resistente a múltiples antibióticos.

Abstract: Objective: To determine the serotype and antibiotic resistance profile of Salmonella spp. isolated from retail ground beef in Mexico City. Materials and methods: A total of 100 samples of ground beef were analyzed. The pathogen was isolated by conventional methods and confirmed by PCR (invA gene, 284 bp).The antibiotic resistance profile was determined by the Kirby-Bauer method while serotyping was performed according to the Kauffman-White scheme. Results: We isolated a total of 19 strains of Lomita (6), Derby (4), Senftenberg (2), Javiana and Cannsttat (1) and undetermined (5) serotypes. The strains showed a high resistance rate to ampicillin (18/19), carbenicillin (16/19), tetracyclin (13/19), and trimethoprim-sulfamethoxazole (13/19). Multidrug resistance was observed in 14 isolates. Conclusions: Several Salmonella spp. serotypes of public health significance are circulating in ground beef sold in the major Mexican city. Some of these strains are multi-drug resistance.

Biocide tolerance in Salmonella from meats in Southern Spain

Salmonella serovars sampled from meat products in Southern Spain (Andalucía) during the period 2002-2007 were analyzed in this study. The serovars most frequently detected (in order) were Typhimurium, Enteritidis, Derby, Anatum and Rissen. Isolates (n = 43) were tested for sensitivity to biocides, including the quaternary ammonium compounds benzalkonium chloride (BC), cetrimide (CT) and hexadecylpyridinium chloride (HDP), and the bisphenols triclosan (TC) and hexachlorophene (CF). The minimum inhibitory concentration (MIC) for the quaternary ammonium compounds was in the range of 25 to 50 mg/L for most isolates, although a few isolates required much higher concentrations, up to 250 mg/L. Bisphenols showed higher inhibitory activity, with a MIC of 2.5 to 25 mg/L. A few isolates showed a “non-wildtype” MIC for TC of up to 250 mg/L. These results indicate a low incidence of tolerance towards quaternary ammonium compounds and triclosan among Salmonella from meats and meat products.

Incorporação de antimicrobianos naturais em filme biodegradável à base de alginato para o controle de Listeria monocytogenes em embutido cárneo fatiado / Incorporation of natural antimicrobials into alginate based film for the control of Listeria monocytogenes in sliced meat product

A incorporação de substâncias antimicrobianas, entre elas os óleos essenciais, em embalagens tem como objetivo minimizar a contaminação microbiana em alimentos. No entanto, essa utilização é limitada por critérios sensoriais, sendo necessário determinar a concentração mínima necessária para inibir o desenvolvimento de micro-organismos sem afetar sensorialmente as características do alimento. Assim, os objetivos dessa pesquisa foram: determinar a concentração inibitória mínima (CIM) de óleos essenciais (OE) para Listeria monocytogenes (LM); avaliar do efeito da combinação de óleos essenciais para a redução da população de LM; avaliar a combinação de compostos ativos presentes em óleos essenciais para a inibição de LM, Pseudomonas spp e Salmonella spp; avaliar in vitro e in situ a eficiência antimicrobiana do filme à base de alginato incorporado de compostos ativos presentes em óleos essenciais; determinar a disponibilidade dos compostos ativos incorporados ao filme pela determinação dos compostos fenólicos totais; caracterizar o filme frente às propriedades mecânicas e propriedades de barreira, e verificar a aceitação pelo consumidor, através da análise sensorial, de fatias de salame embaladas com o filme antimicrobiano. Constatou-se que a combinação de eugenol (0,01%) e limoneno (0,04%) apresentou um maior efeito para a redução da população de LM comparado ao uso individual desses compostos, confirmando, portanto, a existência de sinergismo entre esses dois compostos. Em relação à Pseudomonas spp, o sinergismo foi constatado quando as concentrações de eugenol (0,15%) e de limoneno (0,30%) foram utilizadas, no entanto, para Salmonella spp o mesmo efeito não foi observado. Em ensaios in vitro apesar do aumento na concentração de eugenol e limoneno incorporados à matriz do filme, não houve diferença significativa para os valores de zona de inibição antimicrobiana porém, em ensaios in situ, a utilização desse filme como embalagem primária promoveu a redução de 2 log UFC/g da população de LM até o 10º dia de análise permanecendo constante até o 30º dia o que não ocorreu com a combinação de eugenol (0,15%) e limoneno (0,3%). A quantificação dos compostos fenólicos totais nas amostras mostrou que há correlação entre o teor de compostos fenólicos extraídos da amostra do filme e o comportamento de LM. As propriedades mecânicas e de barreira do filme à base de alginato não foram significativamente afetadas pelas concentrações de eugenol e limoneno avaliadas neste estudo. O sabor, o aroma e a aparência das amostras de salame foram aceitos pelos provadores mostrando que o uso do filme à base de alginato incorporado com eugenol e limoneno é viável para a aplicação como embalagem antimicrobiana para o controle de L. monocytogenes em salame fatiado. Este resultado é considerado importante, pois em alimentos com atividade de água e valores de pH adequados à multiplicação desse patógeno e armazenados sob refrigeração, a temperatura é capaz de selecionar a microbiota presente no alimento, favorecendo a multiplicação de micro-organismos psicrotróficos, como L. monocytogenes

The incorporation of antimicrobial substances in packages aims at reducing food microbial contamination among which the phenolic compounds extract from plants have received special attention being natural and attending consumer demand. However, the use of these compounds is limited by sensory criteria and it is necessary to determine the minimum concentration required to inhibit the growth of microorganisms without affecting the sensory characteristics of the food. The aim of this research were: to determine the minimum inhibitory concentration (MIC) of essential oils (EO) for Listeria monocytogenes (LM); to evaluate effect of the combination of essential oils in order to reduce LM population; to evaluate the active compounds combination for the inhibition of LM, Pseudomonas spp, and Salmonella spp; to evaluate the antimicrobial efficiency in vitro and in situ of the alginate film incorporated with the active compounds; to determine the availability of the active compounds incorporated into the film for the determination of total phenolic compounds; to characterize the mechanical and barrier properties of the film, and to verify consumer acceptance of slices of salami packaged with the antimicrobial film. The combination of eugenol (0.01%) and limonene (0.04%) showed a greater effect for reducing LM population compared to the individual use of these compounds, confirming the existence of synergism between these two compounds. Regarding Pseudomonas spp, synergism was observed when the concentrations of eugenol (0.15%) and limonene (0.30%) were used, however, the same effect was not observed for Salmonella spp. In in vitro tests, despite of the increase in the concentration of limonene and eugenol incorporated in the film matrix, no significant difference for the antimicrobial inhibition zone values was observed. In in situ tests, the film containing eugenol (0.3%) and limonene (0.6%) promoted the reduction of 2 log CFU/g of LM population in sliced salami, while the combination of eugenol (0.15%) and limonene (0.3%) did not have the same effect. The quantification of the phenolic compounds in the film samples showed that there is correlation between the content of phenolic compounds extracted from the film sample and LM behavior. The mechanical properties of the barrier film and the alginate were not significantly affected by eugenol, and limonene concentrations evaluated in this study. The taste, flavor and appearance of the salami samples were accepted by the panel showing that the use of the alginate-based film incorporated with limonene and eugenol are feasible for use as antimicrobial packaging for the control of L. monocytogenes in sliced salami. This is an important result, because in food matrix with water activity and pH suitable for the pathogen growth, the storage under refrigerated condition is able to select the psycrothophic microorganisms, such as L. monocytogenes

Salmonella Alachua: causative agent of a foodborne disease outbreak

Objectives: The aim of this study is to report the occurrence of the first outbreak of food poisoning caused by Salmonella Alachua in Brazil, as well as the antimicrobial susceptibility and the genetic relatedness of Salmonella Alachua strains isolated from clinical and food samples. Material and methods: To elucidate the outbreak, an epidemiological investigation was carried out, and two samples of common food were tested - mayonnaise salad and galinhada (a traditional Brazilian dish of chicken and rice) - according to the Compendium of methods for the microbiological examination of foods. Five stool samples were tested employing classic methods for the isolation and identification of enterobacteria. Strains of Salmonella were characterized for antibiotic susceptibility according to the Clinical and Laboratory Stan- dards Institute guidelines (2013), and submitted to pulsed-field gel electrophoresis analysis, performed according to the Centers for Disease Control and Prevention PulseNet protocol. Results: A total of 94 people were interviewed after ingesting the food, 66 of whom had become ill. A 60-year old female patient who was hospitalized in a serious condition, developed septic shock and died two days after consuming the food. The presence of Salmonella Alachua was confirmed in all the analyzed stool samples, and in the two types of food. The five strains showed higher than minimum inhibitory concentration values of nalidixic acid (≥256 µg/mL) and reduced ciprofloxacin susceptibility (minimum inhibitory concentration = 0.5 µg/mL). The pulsed-field gel electrophoresis analysis revealed indistinguishable patterns in Salmonella Alachua strains isolated from clinical and food samples. Conclusion: The data presented herein confirm the foodborne disease outbreak. They also allowed for the identification of the source of infection, and suggest that products from poultry are potential reservoirs for this serotype, reinforcing the ...

Salmonella Yeerongpilly in a Chinese Owl (Columba livia domestica) in Jamaica.

Salmonella infection in bird species in Jamaica was studied. This revealed that very low prevalence of salmonellosis was found (0.32 %). Salmonella Yeerongpilly (newly reported in the country) was isolated from a bird collected at a bird aviary. This study showed that there was the presence of this Salmonella serovar in a Chinese owl (Columba livia domestica) in Jamaica. There were not published reports from Caribbean Islands of the presence of this serovar. Salmonella Yeerongpilly belongs to serogroup E1 and by molecular serotyping random amplification of polymorphic DNA (RAPD) fingerprinting belongs to A20, B17 and C21. This strain was isolated in Queensland Australia in the 1960s before the successful Salmonella eradication campaign. This study suggests that a larger investigation in pet birds as Salmonella carriers should be carried out in Jamaica. Mandatory screening or quarantine of birds entering the country should be institutionalized.

Occurrence of Salmonella spp. and generic Escherichia coli on beef carcasses sampled at a brazilian slaughterhouse

A total of 120 beef carcasses were analyzed during processing at a slaughterhouse in southern Brazil. The carcasses were sampled by swab at three different steps of the slaughter line and then they were tested for Salmonella and E. coli. The Salmonella isolates were also examined for antimicrobial susceptibility. Salmonella prevalence distribution was modeled and the probability of contamination was simulated using @Risk program and 10,000 interactions. Results demonstrated that 4 beef carcasses (3.3%) were positive for Salmonella only in the first point. The six isolates of Salmonella were classified: S. Newport (n = 3), S. Saintpaul (n = 2) and S. Anatum (n = 1). No Salmonella strains exhibited resistance to any of the antimicrobials tested. As expected, the most contaminated point with E. coli was the first point (hide), presenting counts from 0.31 to 5.07 log cfu/100 cm². Much smaller E. coli counts were observed in the other points. Results indicated low levels of Salmonella and E. coli on the beef carcasses analyzed and also low probability of contamination of the carcasses by Salmonella, suggesting adequate microbiological quality.

Distribution, quantitative load and characterization of Salmonella associated with swine farms in upper-northern Thailand

This study was conducted to analyze the prevalence and quantitative loads of Salmonella spp. on pig farms in Chiang Mai, Lamphun, Thailand to assess loading levels before slaughtering. The serotype diversity, antimicrobial-resistance pattern and pulse-field type of Salmonella spp. were also characterized to assess the dynamic propagation of the pathogen. The Salmonella-positive prevalence was 246/805 (30.56%), and the quantitative loads varied from 1.48~4.04 Log10MPN/g, with a mean +/- standard deviation of 2.11 +/- 0.57. AMP/S/TE (ampicillin/streptomycin/tetracycline) was the highest frequency antimicrobial resistance pattern found in this study. In addition, Salmonella Rissen was the primary serotype in this region. PFGE results indicated the occurrence of infection by cross contamination among pig farms. Our study showed that pork is easily contaminated with this pathogen. Farm control programs must be based on strict biosecurity and hygienic measures, which could further reduce the contamination pressure at slaughterhouses or retail shops.

Commercially laid eggs vs. discarded hatching eggs: contamination by Salmonella spp

Salmonella enterica is frequently associated with outbreaks of human salmonellosis, and products of avian origin, such as eggs and chicken meat, are the main vehicles of its transmission. The present study describes the occurrence of different serovars of Salmonella enterica and phagotypes of S. enterica serovar Enteritidis in eggs destined for human consumption. Four thousand eggs obtained from commercial egg laying farms and one thousand discarded hatching eggs from broiler farms, which were acquired at farmers' markets and informal shops, were analyzed. Salmonella spp. was isolated from 52.0% of the discarded hatching eggs, in which the predominant serovar was Enteritidis (84.6%), and the predominant Salmonella Enteritidis phagotype (PT) was PT7 (26.9%). Salmonella spp. was not isolated from eggs obtained from commercial egg laying farms. The antimicrobial resistance profile showed that 23.1% (n = 6) of the SE strains were resistant to nalidixic acid. The results suggest that the consumption of discarded hatching eggs represents an important source of Salmonella transmission to humans.

Molecular characterization of Salmonella strains in individuals with acute diarrhea syndrome in the State of Sucre, Venezuela / Caracterização molecular de cepas de Salmonella em indivíduos com síndrome da diarreia aguda no Estado de Sucre, Venezuela

INTRODUCTION:In Venezuela, acute diarrheic syndrome (ADS) is a primary cause of morbi-mortality, often involving the Salmonella genus. Salmonella infections are associated with acute gastroenteritis, one of the most common alimentary intoxications, and caused by the consumption of contaminated water and food, especially meat. METHODS: Conventional and molecular methods were used to detect Salmonella strains from 330 fecal samples from individuals of different ages and both sexes with ADS. Polymerase chain reaction (PCR) was used for the molecular characterization of Salmonella, using invA, sefA, and fliC genes for the identification of this genus and the serotypes Enteritidis and Typhimurium, respectively. RESULTS: The highest frequency of individuals with ADS was found in children 0-2 years old (39.4%), and the overall frequency of positive coprocultures was 76.9%. A total of 14 (4.2%) strains were biochemically and immunologically identified as Salmonella enterica subsp. enterica, of which 7 were classified as belonging to the Enteritidis serotype, 4 to the Typhimurium serotype, and 3 to other serotypes. The S. enterica strains were distributed more frequently in the age groups 3-4 and 9-10 years old. CONCLUSIONS: The molecular characterization method used proved to be highly specific for the typing of S. enterica strains using DNA extracted from both the isolated colonies and selective enrichment broths directly inoculated with fecal samples, thus representing a complementary tool for the detection and identification of ADS-causing bacteria.

INTRODUÇÃO: Na Venezuela, síndrome da diarreia aguda (SDA) é a principal causa de mórbi-mortalidade, muitas vezes envolvem o gênero Salmonella. Infecções por Salmonella são associadas com gastroenterite aguda, uma das mais comuns intoxicações alimentares causada pelo consumo de água e alimentos contaminados, principalmente carne. MÉTODOS: Métodos convencionais e moleculares foram usados para detectar cepas de Salmonella em 330 amostras de fezes de indivíduos com SDA de diferentes idades e ambos os sexos. A reação em cadeia da polimerase (PCR) foi utilizada para a caracterização molecular de genes Salmonella invA, sefA e fliC para identificar o gênero e os sorotipos Enteritidis e Typhimurium, respectivamente. RESULTADOS: A maior frequência de indivíduos com SDA foi encontrada em crianças de 0-2 (39,4%) anos, e a frequência total de culturas de fezes positiva foi de 76,9%. Um total de 14 (4,2%) cepas foram bioquímica e imunologicamente identificados como Salmonella enterica subsp. enterica, dos quais 7 foram classificados como pertencentes ao sorotipo Enteritidis, Typhimurium sorotipo 4 e 3 para outros sorotipos. Cepas S. enterica foram distribuídas mais frequentemente em grupos de 3-4 e 9-10 anos de idade. CONCLUSÕES: O método de caracterização molecular usada provou ser altamente específico para tipificar as estirpes dos S. enterica usando tanto DNA extraído de colônias isoladas e direta e caldos de enriquecimento seletivo inoculados com amostras fecais, o que representa uma ferramenta complementar para a detecção e identificação de bactérias que causam a SDA.

Prevalence and antimicrobial resistance of Salmonella in chicken carcasses at retail in 15 Brazilian cities / Prevalencia y resistencia a los antimicrobianos de Salmonella en polloscongelados de venta al por menor en 15 ciudades del Brasil

Objetivo. Describir la prevalencia y la resistencia a los antibióticos de Salmonella spp. en canales de pollo congeladas de venta al por menor en 15 ciudades del Brasil. Métodos. Entre septiembre del 2004 y julio del 2006 se llevó a cabo un estudio descriptivo de los datos del Programa Nacional Brasileño de Vigilancia de la Prevalenciade la Resistencia Bacteriana en el Pollo (PREBAF). Durante el programa serecolectaron canales de pollo en 15 capitales estatales del Brasil, en las cinco regiones geográficas del país. Para aislar Salmonella spp. e identificar los serotipos, se usaron las técnicas convencionales. Para evaluar la resistencia frente a 18 antibióticos, se usó el método de la concentración inhibitoria mínima. Resultados. En las 2 679 canales de pollo examinadas, la prevalencia de Salmonella spp. fue de 2,7% (amplitud, 0,0%–8,9%). El 50,6% de las muestras positivas provinieron del estado de São Paulo. Se identificaron 18 serotipos. Los más frecuentes fueron Salmonella Enteritidis (48,8%), Salmonella Infantis (7,6%), Salmonella Typhimurium (7,2%) y Salmonella Heidelberg (6,4%). Las 250 cepas evaluadas fueron resistentes auno o más antibióticos, y 133 (53,2%) fueron multirresistentes (≥ 3 clases de antibióticos). Salmonella Heidelberg fue resistente a la ceftriaxona (75,0%) y al ceftiofur (43,8%). Conclusiones. La prevalencia de Salmonella spp. en este estudio fue relativamente baja. Sin embargo, hubo una proporción elevada de cepas multirresistentes, inclusivea las cefalosporinas de tercera generación usadas para tratar la salmonelosis invasora. Los resultados confirman la relevancia del programa PREBAF, el cual se recomienda mejorar, por ejemplo, mediante un análisis oportuno de los datos. También es necesario revisar los límites permitidos de Salmonella spp. en el pollo que se vende al por menor en el Brasil.

Objective. To describe the prevalence and antimicrobial resistance of Salmonella spp. in frozen chicken carcasses at retail from 15 Brazilian cities. Methods. A descriptive study of data from the Brazilian National Program for Monitoring the Prevalence of Bacterial Resistance in Chicken (PREBAF) was conducted from September 2004 to July 2006. The program collected chicken carcasses in 15 state capitals of Brazil inthe five geographic regions of the country. Standardized methodologies were used to isolate Salmonella spp. and identify serotypes. The minimal inhibitory concentration method wasused to test resistance to 18 antimicrobials. Results. In 2 679 carcasses examined, the prevalence of Salmonella spp. was 2.7% (range0.0%–8.9%). São Paulo State produced 50.6% of positive samples. Eighteen serotypes were identified. The most frequently occurring were Salmonella Enteritidis (48.8%), Salmonella Infantis (7.6%), Salmonella Typhimurium (7.2%), and Salmonella Heidelberg (6.4%). All 250 strains tested were resistant to one or more antibiotics, and 133 (53.2%) were multidrug resistant (≥ 3 classes). S. Heidelberg was resistant to ceftriaxone (75.0%) and to ceftiofur (43.8%).Conclusions. The prevalence of Salmonella spp. found in this study was relatively low. However, there were a high proportion of multidrug-resistant strains, including thirdgenerationcephalosporins used to treat invasive salmonellosis. The results confirm the relevance of the PREBAF program. It is recommended that PREBAF be improved, including a timely data analysis. A review of permitted limits for Salmonella spp. in retail chicken in Brazil is also needed.

Serovariedades y patrones de susceptibilidad a los antimicrobianos de cepas de Salmonella aisladas de alimentos en Cuba / Serotypes and antimicrobial susceptibility patterns of Salmonella strains isolated from food in Cuba

The serotypes of 178 isolates of Salmonella enterica taken from food in different regions of Cuba between January 2008 and December 2009 were identified, and the antimicrobial susceptibility pattern of 100 selected isolates was determined by stratasampling. A total of 20 Salmonella serotypes were identified, with a predominance of S. Enteritidis (23%), S. Agona (13.5%), and S. London (11.2%). Of all the strains, 75%were resistant or presented intermediate resistance to at least one of the drugs tested, in the following order: tetracycline (70.7%), ampicillin (22.7%), and nalidixic acid (14.7%). Ten different resistance patterns were identified. The most frequent patternscorresponded to strains that were either drug-resistant or had intermediate resistance (89.3%). Three strains (identified as S. Infantis, S. Derby, and S. Enteritidis) were multiresistant, and one of them, S. Enteritidis, was not sensitive to either nalidixic acid or ciprofloxacin. To control salmonellosis, the importance of maximizing integrated health surveillance is emphasized.

Se describen los serotipos de 178 cepas de Salmonella enterica aisladas de alimentos en diferentes regiones de Cuba entre enero de 2008 y diciembre de 2009, y el patrón de susceptibilidada los antimicrobianos de 100 aislados seleccionados mediante muestreo por estratos. Se identificaron 20 serovariedades de Salmonella entre las que predominaron S. Enteritidis (23%);S. Agona (13,5%) y S. London (11,2%). Del total, 75% de las cepas fueron resistentes o presentaronresistencia intermedia a al menos uno de los fármacos probados, en el siguiente orden, según su frecuencia: tetraciclina (70,7%); ampicilina (22,7%) y ácido nalidíxico (14,7%). Seidentificaron 10 patrones de resistencia diferentes y predominaron las cepas resistentes o con resistencia intermedia a un fármaco (89,3%). Tres cepas (S. Infantis, S. Derby y S. Enteritidis)fueron multirresistentes y una, de S. Enteritidis, dio un resultado no sensible al ácido nalidíxico y la ciprofloxacina. Se destaca la necesidad de extremar la vigilancia sanitaria integrada en el país para el control de la salmonelosis.

Electroforesis de campo eléctrico pulsado en la tipificación molecular de cepas aisladas de un brote de Salmonelosis ocasionado por consumo de queso contaminado con Salmonella Javiana / Pulse Field Gel Electrophoresis in molecular typification of strains isolated from a Salmonellosis outbreak caused by consumption of Salmonella Javiana contaminated cheese

El objetivo de este trabajo fue confirmar por Electroforesis de Campo Electrico Pulsado (PFGE) que la Salmonella aislada del alimento implicado en el brote (queso blanco) fue la responsable del evento.La muestra de queso blanco presento elevado recuento de coliformes, E. coli y S. aureus,ademas, presencia de Salmo nella spp., lo que indico condiciones sanitarias inadecuadas y posible contaminacion de origen fecal. Para la confirmacion de las cepas sospechosas de Sal monella spp, aisladas de los pacientes y del alimento, se utilizaron tecnicas bioquimicas convencionales, la serotipificacion se realizo siguiendo el esquema de White-kauffmann-LeMinor y la sensibilidad a los antimicrobianos (Ampicilina, Trimetroprim-Sulfametoxazole, Ciprofloxacina, Amoxicilina, Ac.Clavulanico, Cloranfenicol, Ceftriaxone y Tetraciclina) por la tecnica kirby-Bauer. Las cepas bacterianas de Salmonella spp aisladas fueron identificadas como Salmonella Javiana [1,9,12:l, z28:1,5] y resultaron sensibles a todos los antibioticos probados.La Tipificacion Molecular de las cepas, se realizo por PFGE, se gun protocolo estandarizado de PulseNet para Salmonella y el analisis de los patrones se estudio utilizando el programa BioNumerics, version 4.0, lo cual mostro que los aisla dos de Salmonella Javiana procedentes tanto de pacientes como del alimento tenian identico patron de restriccion, en tamano y numero de fragmentos. La ocurrencia de un patron unico de PFGE (Coeficiente de similitud 100%) entre los aislados permitio demostrar que el queso contaminado con Salmonella Javiana fue el responsable del brote familiar.

The aim of this work was confirmation through Pulse Field Gel Electrophoresis (PFGE) that Salmonella isolated from the food implicated in the outbreak (white cheese) was responsible for the event. The white cheese sample showed a high count of Coli orms,f E. coli and S. aureus. Moreover, Salmonella was pre ent,s which indicated inadequate sanitary conditions and possible fecal contamination. The suspected Salmonella strains isolated from patients and the food sample, were confirmed using conventional biochemical techniques, serotyping according to the White-kauffmann-Le Minor scheme and antibiotics sensibility (Am picillin, Trimetroprim-Sulfametoxazole, Ciprofloxacin, Amoxicillin, Clavulanic Acid, Cloranfenicol, Ceftriaxone and tetraciclin) following kirby-Bauer’s technique. The Salmonella strains were identified as Salmonella Javiana [1,9,12:I, z28:1,5]and were sensitive to all the antibiotics tested. The molecular typing of the strains was performed using PFGE, according to the PulseNet standardized protocol for Salmonella. The pattern analysis was studied using Bionunella merics program, version 4.0, which showed that the Sal monella Javiana isolates from patients as the food sample had an identical restriction pattern in size and fragments number. The incidence of a unique pattern of PFGE (similarity coefficient 100%) between isolates demonstrated that the cheese contaminated with Salmonella Javiana was responsible for the family outbreak.

Salmonella Serovars from Foodborne and Waterborne Diseases in Korea, 1998-2007: Total Isolates Decreasing Versus Rare Serovars Emerging

Salmonella enterica has been one of the most widespread foodborne pathogens in Korea. Between 1998 and 2007, a total of 9,472 Salmonella isolates were identified from foodborne and waterborne illness patients. During that time, Korea was transitioning into a developed country in industry as well as in its hygiene system. Although the isolation number of total Salmonella including serovar Typhi has decreased since 1999, the isolation of rare Salmonella serovars has emerged. Three most prevalent serovars during 1998-2007 were S. enterica Typhi, S. enterica Enteritidis, and S. enterica Typhimurium. There were remarkable outbreaks caused by rare serovars such as S. enterica Othmarschen, S. enterica London and S. enterica Paratyphi A, and overseas traveler-associated infections caused by S. enterica Weltevreden and S. enterica Anatum. Salmonella serovars from overseas travelers made a diverse Salmonella serovar pool in Korea. This study is the first review of the status of the human Salmonella infection trend in a developing country during 1998-2007. Newly emerging rare Salmonella serovars should be traced and investigated to control new type pathogens in the developed world.

Evolución de los serotipos, fagotipos y resistencia a antimicrobianos de Salmonella sp en el departamento de salud 02 de la provincia de Castellón, España (2000-2006) / Evolution of serotypes, phagotypes and antibiotic resistance of Salmonella spp in the 02 health district of Castellón, Spain (2000-2006)

Retrospective study of serotypes, phage types and antibiotic resistance of Salmonella spp isolates in the 02 Health District of Castellón, Spain (2000-2006). Strains were serotyped using commercial sera, and they were tested for antimicrobial susceptibility with automated systems. Serotyping confirmation and phage typing were performed by the National Reference Laboratory. A total of 1505 strains were isolated, with 49 different serotypes, being the most frequent Enteritidis. The most common serotype/phage type combination was S. Enteritidis phagetype 1. Of the isolates 81.6 percent were susceptible to amoxicillin/clavulanic acid; 65.2 percent to ampicilin; 99.9 percent to ciprofloxa-cin; 93.4 percent to trimethoprim-sulphametoxazole; and 99.8 percent to cefotaxime. Molecular methods could be useful to complete epidemiologic studies since 25 percent of our isolates showed the same serotype/phage type combination. In our health district antimicrobial resistance in Salmonella is not an important problem.

Comparative analysis of codon usage patterns and identification of predicted highly expressed genes in five Salmonella genomes.

PURPOSE: To analyse codon usage patterns of five complete genomes of Salmonella , predict highly expressed genes, examine horizontally transferred pathogenicity-related genes to detect their presence in the strains, and scrutinize the nature of highly expressed genes to infer upon their lifestyle. METHODS: Protein coding genes, ribosomal protein genes, and pathogenicity-related genes were analysed with Codon W and CAI (codon adaptation index) Calculator. RESULTS: Translational efficiency plays a role in codon usage variation in Salmonella genes. Low bias was noticed in most of the genes. GC3 (guanine cytosine at third position) composition does not influence codon usage variation in the genes of these Salmonella strains. Among the cluster of orthologous groups (COGs), translation, ribosomal structure biogenesis [J], and energy production and conversion [C] contained the highest number of potentially highly expressed (PHX) genes. Correspondence analysis reveals the conserved nature of the genes. Highly expressed genes were detected. CONCLUSIONS: Selection for translational efficiency is the major source of variation of codon usage in the genes of Salmonella . Evolution of pathogenicity-related genes as a unit suggests their ability to infect and exist as a pathogen. Presence of a lot of PHX genes in the information and storage-processing category of COGs indicated their lifestyle and revealed that they were not subjected to genome reduction.

A food borne outbreak of gastroenteritis due to shigella and possibly salmonella in a school.

On August 5, 2005, a private hospital reported a large number of students with gastrointestinal illness from the same school in Bangkok, Thailand. The Bureau of Epidemiology along with the Bangkok Metropolitan Administration investigated this outbreak, to determine risk factors, identify the source of infection and possible causative organism, and recommend prevention and control strategies. A case was defined as a person who was studying or working at School A and who developed abdominal pain, diarrhea, nausea or vomiting during the five-day period of August 4 to 8, 2005. A descriptive study was carried out for active case-finding, medical records review, and case interviews. We conducted the retrospective cohort study among third and fourth grade students. Stool samples were collected and tested at the Thai National Institute of Health and at private hospital laboratories. The overall attack rate was 37%. Main symptoms were diarrhea, fever, headache, abdominal pain, vomiting, and nausea. The highest attack rate (63%) was among fourth-grade students. Based on food-history data collected from ill and well students, a multiple logistic regression analysis showed that a mixed chicken and rice dish served for lunch on August 4 was associated with illness (OR 3.28, 95% CI 1.46-7.36). Among stools samples from 103 cases, Shigella group D was found in 18 cases, Salmonella group C in 5 cases, and Salmonella group E in 2 cases. This food borne outbreak of gastroenteritis was most likely caused by Shigella spp although the possibility of mixed contamination with Shigella and Salmonella spp cannot be ruled out. Food borne outbreaks such as this can be prevented through simple and effective hygienic measures.