ABSTRACT Salmonellosis ranks among the most frequently reported zoonosis worldwide and is often associated with foodborne outbreaks. Since the 1950s, the distribution of Salmonella serotypes in Sao Paulo State, Brazil, has been documented and periodically reported. In this study, we updated the data on the distribution of Salmonella serotypes received in our reference laboratory, isolated from human infections and nonhuman sources, from 2004 to 2020. In that period, a total of 9,014 Salmonella isolates were analyzed, of which 3,553 (39.4%) were recovered from human samples, mainly of stool (65%) and blood (25.6%), and 5,461 (60.6%) were isolated from nonhuman origins, such as animals (47.2%), food (27.7%) and animal environments (18.6%). In human isolates, a total of 104 serotypes were identified and the most frequent ones were Enteritidis, Typhimurium, S . I. 4,[5],12:i:-, Dublin and Typhi. A consistent reduction of the Enteritidis proportion was observed over the years. Among the 156 serotypes identified in isolates with nonhuman origins, Enteritidis, Mbandaka, Typhimurium, Agona and Anatum were ranked as the top five Salmonella serotypes; in more recent years, S . Heidelberg has increased in frequency. Although with different proportions, the top 10 prevalent serotypes were identified in both human and nonhuman origins, underscoring the role of animals, food products and environment as reservoirs of Salmonella with potential to cause human salmonellosis.

Objectives: The aim of this study is to report the occurrence of the first outbreak of food poisoning caused by SalmonellaAlachua in Brazil, as well as the antimicrobial susceptibility and the genetic relatedness of SalmonellaAlachua 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 SalmonellaAlachua 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 SalmonellaAlachua 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 importance of warning consumers about the danger of possible contamination.

A total of 283 Salmonella Typhimurium strains isolated from cases of human infections and non human sources, were examined for antimicrobial susceptibilityand the incidence of resistance was 38% and multiple resistance (to three or more antimicrobials) was 15%. All 43 multidrug-resistant strains (MDR) and 13 susceptible ones were characterized by phage typing and pulsed- field gel electrophoresis (PFGE). The strains encompassed 14 definitive phage types (DT), three were untypable (UT), and 18 atypicals or reaction does not conform (RDNC), which belonged to 21 PFGE patterns, A1-A21. The predominant phage types were DT49, DT193, and RDNC and two strains belonging to DT 104 and 104b were also identified. The most commum PFGE patterns were A1 and A8. Analysis by PFGE and phage typing demonstrated that the most of the MDR were multiclonal and association among multiresistance, phage typing, and PFGE patterns was not so significant.

INTRODUÇÃO: Na identificação de cepas de Salmonella, os métodos de sorotipagem e ribotipagem na detecção de marcadores epidemiológicos são os mais utilizados nos laboratórios de referência mundiais. Esses métodos moleculares são imprescindíveis na vigilância epidemiológica e permitem a detecção da fonte da infecção. OBJETIVOS: O presente trabalho objetivou caracterizar as cepas de Salmonella Enteritidis pela ribotipagem. MATERIAL E MÉTODOS: Trinta e oito cepas de S. Enteritidis foram isoladas de pacientes atendidos no Hospital das Clínicas da Universidade de São Paulo, Ribeirão Preto, SP, entre os anos de 1996 e 1998. As cepas foram isoladas de fezes (31 amostras), sangue (quatro amostras) e outros fluidos (três amostras). As cepas de Salmonella foram isoladas utilizando-se métodos bacteriológicos de rotina, sorotipadas e ribotipadas. RESULTADOS: As 38 cepas de S. Enteritidis apresentaram na ribotipagem a separação das cepas em dois ribotipos: A (94,7% das amostras) e B (5,3% das amostras). DISCUSSÃO E CONCLUSÃO: Esses dados sugerem que grande parte dos pacientes (94,7%) foi infectada pela mesma cepa. Essa cepa pode ser endêmica na comunidade de Ribeirão Preto ou os pacientes foram expostos a uma fonte comum de infecção.

BACKGROUND: The approach generally employed in leading laboratories worldwide to identify strains of Salmonella is to detect epidemiological markers by serotyping and molecular techniques. These molecular methods are important in sanitary surveillance and lead to the source of infection. OBJECTIVES: The aim of the present study is to characterize Salmonella Enteritidis strains by ribotyping. MATERIAL AND METHODS: Thirty-eight strains of S. Enteritidis were isolated from in patients at the university hospital of Universidade de São Paulo, Ribeirão Preto, SP, Brazil, between 1996 and 1998. These strains were isolated from stools (31 samples), blood (4 samples) and other body fluids (3 samples), using routine bacteriological methods, and were serotyped and ribotyped. RESULTS: The 38 strains of serotype S. Enteritidis were shown by the ribotyping to belong to two ribotypes: A (94.7% of the samples) and B (5.3%). DISCUSSION AND CONCLUSION: These results suggest that the majority of patients (94.7%) were infected by the same strain. This strain could be endemic in the Ribeirão Preto community, or these patients may have been exposed to a common source of infection.

O objetivo deste estudo foi analisar o perfil de resistência à antimicrobianos, de Salmonella isoladas de 21 amostras provenientes de pacientes com sintomatologia de gastroenterite. Verificou-se que S. enteritidis foi o sorotipo com maior prevalência. Estas cepas mostraram-se sensíveis à maioria dos antimicrobianos testados, no entanto, as cepas S. typhimurium e S. enterica subsp. enterica sorotipo 4,5,12:i:-, mostraram-se resistentes à vários antimicrobianos. Vigilância e um monitoramento eficiente, para diminuir a resistência antimicrobiana em microrganismos que causam infecções veiculadas por alimentos, devem ser prioridade para a saúde pública.

The purpose of this study was to analyse the profile of antimicrobial resistance among 21 strains of Salmonella isolated from patients with gastroenteritis symptom. It was observed that S. enteritidis was the serotype prevalent. These strains were sensitive to the majority of the antimicrobials tested, however, high resistance was observed in S. typhimurium and S. enterica subsp. enterica serotype 4,5,12:i:-. Surveillance and an efficient monitoring should be priority for the public health for the containment of antimicrobial resistance in foodborne infections.

Com o objetivo de caracterizar os principais enteropatógenos causadores de diarréia na região de Ribeirão Preto, quanto aos sorogrupos e sorotipos, por um período de 4 anos foram estudadas fezes de 1836 crianças, menores de 10 anos de idade, de ambos os sexos, portadoras de gastrenterite aguda no IAL de Ribeirão Preto, SP. Foram pesquisados os seguintes enteropatógenos: Escherichia coli, Salmonella sp., Shigella sp., Campylobacter sp., Yersinia sp., e Cryptosporidium sp., identificados através de metodologia tradicional. Foram positivas 419 (22,8%) amostras, com 1,7% de associação entre enteropatógenos. Houve predomínio na faixa etária de 0 a 11 meses. Destacou-se a E.coli enteropatogênica (EPEC) (8,7%), sendo mais frequente o sorogrupo O119 (40,2%), seguida do gênero Shigella (6,2%), dos quais 63,2% corresponderam à S. sonnei.

To study the main enteropathogens causing diarrhea in the region of Ribeirão Preto regarding serogroups and serotypes, the feces of 1836 children under 10 years old, from both sexes, attack of acute gastroenteritis, were analysed during a period of 4 years in Adolfo Lutz Institute - Ribeirão Preto, SP. The pathogens identified by standard methods were the following: Escherichia coli, Salmonella spp., Shigella spp., Campylobacter spp., Yersinia spp., and Cryptosporidium spp. Positive samples were 22.8% (419) with 1.7% association of pathogens. Larger isolates were mainly from children 0 to 11 months old. Enteropathogenic E. coli (EPEC) was most frequent (8.7%) with predominance of serogroup O119 (40.2%), followed by Shigella (6.2%), 63.6% of which S. sonnei.

Foram examinadas caixas de transporte de pintos de um dia com o objetivo de investigar a presença de Salmonella no momento em que chegaram à granja. 1611 caixas foram amostradas em 15 propriedades, sendo uma granja de avós, quatro granjas de matrizes, duas de frangos de corte e seis de aves de postura comercial. Foram feitas 19 visitas a essas granjas e Salmonella foi encontrada em 10 delas. Salmonella Heidelberg foi encontrada em caixas de cinco granjas, S. Heidelberg e S. Mbandaka em caixa de uma granja de matriz. S. Enteritidis somente, S. Enteritidis e S. Mbandaka simultaneamente, e S. Cerro somente, foram detectadas em caixas de três, uma e uma granjas de postura comercial, respectivamente.

The presence of Salmonella was investigated in transport boxes of newly hatched chicks in the moment they were received in the farms. 1,611 boxes, delivered to 15 farms (one broiler grand-parent farm, four broiler parent farms, two commercial broiler chick farms and seven laying hens farms) were tested. A total of 19 visits to these farms were done, and Salmonella was detected in ten of these visits. Salmonella Heidelberg was detected in boxes in five farms. S. Heidelberg and S. Mbandaka were simultaneously detected in one broiler breeder farm. Salmonella Enteritidis alone, S. Enteritidis and S. Mbandaka and S. Cerro alone were detected in three, one and one laying hens farms, respectively.

Entre as cepas de S. typhimurium e S. agona isoladas no período 1971-1987 foram caracterizados os biotipos, colicinotipos e antibiotipos de 734 cepas de S. typhimurium e 631 de S. agona. As 734 cepas de S. typhimurium foram classificadas em 65 biotipos com o predomínio dos biotipos 1a com 28,34%, 1b com 29,84% e 9bi com 18,25%. Com relação a S. agona, o biotipo 1a com 87,16% representou entre nós o clone amplamente disseminado. Foram encontradas freqüências baixas de cepas colicinogênicas, entretanto, a colicinotipia parece ser um bom método quando aplicada ao estudo de amostras homogêneas provenientes de surtos. Acentuada multirresistência aos agentes antimicrobianos, foi observada principalmente entre aquelas cepas de origem humana quase sempre representadas por cepas hospitalares

Among S. typhimurium and S. agona strains isolated during the period from 1971 to 1987, the biotypes, colicine types and resistance patterns were determined for 734 S. typhimurium and 631 S. agona strains. Among 734 S. typhimurium strains 65 biotypes were disclosed with prevalence of biotypes 1a (28,34%), 1b (29,84%) and 9bi (18,28). Concerning S. agona, the biotype 1a represented by 87,16%, was the commonest clone among our strains. Although colicine typing added little information to characterize these serotypes, it should be usefull when applied in epidemilogical study of outbreaks. It was observed multiply antimicrobial resistance mainly among human strains, particularly from nosocomial origins.