Staphylococcus aureus Isolated From Traditional Artisanal Raw Milk Cheese from Southern Brazil: Diversity, Virulence, and Antimicrobial Resistance Profile.

Staphylococcus aureus is one of the primary pathogenic agents found in cheeses produced with raw milk. Some strains of S. aureus are enterotoxigenic, possessing the ability to produce toxins responsible for staphylococcal food poisoning when present in contaminated foods. This study aimed to genotypically characterize, assess the antimicrobial resistance profile, and examine the enterotoxigenic potential of strains of S. aureus isolated from artisanal colonial cheese. Additionally, a bacterial diversity assessment in the cheeses was conducted by sequencing the 16S rRNA gene. The metataxomic profile revealed the presence of 68 distinct species in the cheese samples. Fifty-seven isolates of S. aureus were identified, with highlighted resistance to penicillin in 33% of the isolates, followed by clindamycin (28%), erythromycin (26%), and tetracycline (23%). The evaluated strains also exhibited inducible resistance to clindamycin, with nine isolates considered multidrug-resistant (MDR). The agr type I was the most prevalent (62%) among the isolates, followed by agr type II (24%). Additionally, ten spa types were identified. Although no enterotoxins and their associated genes were detected in the samples and isolates, respectively, the Panton-Valentine leukocidin gene (lukS-lukF) was found in 39% of the isolates. The presence of MDR pathogens in the artisanal raw milk cheese production chain underscores the need for quality management to prevent the contamination and dissemination of S. aureus strains.

Graduate Student Literature Review: Enterotoxigenic potential and antimicrobial resistance of staphylococci from Brazilian artisanal raw milk cheeses.

More than 30 types of artisanal cheeses are known in Brazil; however, microorganisms, such as Staphylococcus spp., can contaminate raw milk cheeses through different sources, from milking to processing. Staphylococcal food poisoning results from the consumption of food in which coagulase-positive staphylococci, mostly Staphylococcus aureus, have developed and produced enterotoxins. In addition, an emerging public health concern is the increasing antimicrobial resistance of some Staphylococcus strains. Furthermore, the ability of Staphylococcus spp. in sharing antibiotic resistance-related genes with other bacteria increases this problem. In light of these observations, this review aims to discuss the presence of, enterotoxins of, and antibiotic-resistant of Staphylococcus spp. in Brazilian artisanal cheese produced with raw milk.

Human leptospirosis: occurrence of serovars of Leptospira spp. in the state of Minas Gerais, Brazil, from 2008 to 2012

Abstract Background: Leptospirosis is an infectious and acute disease caused by Leptospira spp. that have high epidemic potential. This study verified the main Leptospira spp. serovars detected by MAT from serum of patients with suspicion of leptospirosis from 2008 to 2012 in Minas Gerais State. Methods: The laboratory received sera from 4654 patients. All serum were screened by IgM-ELISA according to the manufacturer's instructions. Each sample reactive or indeterminate were tested against twenty-four serovars of Leptospira by MAT. Results: In this study, 597 patients were classified as reactive on MAT. Only 301 patients were confirmed by laboratory test. It was not possible confirmation by laboratory diagnosis of 296 patients. Among the samples classified as reactive on MAT, 273 patients exhibited titers bigger than 800 for one or more serovars; seroconversion was detected in 28 cases. Percentage of 85.1% of the samples reactive on MAT corresponded to males, 39.4% corresponded to patients aged between 20 and 39 years old. The most common serovars found were Icterohaemorrhagiae, Andamana, Patoc, Tarassovi, Copenhageni, Hardjo and Australis. Concerning the samples that exhibited titers bigger than 800, serovar Icterohaemorrhagiae was also the most common, followed by Copenhageni, Andamana, Patoc, Tarassovi, Grippotyphosa and Canicola. In this study, 40% of the cases occurred to the metropolitan area, state capital and 34 neighboring towns. Conclusion: Our results show the possibly spreading serovars in Minas Gerais State and contribute to knowledge of human leptospirosis, aiming at improving the prevention, control of the disease, as well as the treatment of infected patients.

Human leptospirosis: occurrence of serovars of Leptospira spp. in the state of Minas Gerais, Brazil, from 2008 to 2012.

BACKGROUND: Leptospirosis is an infectious and acute disease caused by Leptospira spp. that have high epidemic potential. This study verified the main Leptospira spp. serovars detected by MAT from serum of patients with suspicion of leptospirosis from 2008 to 2012 in Minas Gerais State. METHODS: The laboratory received sera from 4654 patients. All serum were screened by IgM-ELISA according to the manufacturer's instructions. Each sample reactive or indeterminate were tested against twenty-four serovars of Leptospira by MAT. RESULTS: In this study, 597 patients were classified as reactive on MAT. Only 301 patients were confirmed by laboratory test. It was not possible confirmation by laboratory diagnosis of 296 patients. Among the samples classified as reactive on MAT, 273 patients exhibited titers bigger than 800 for one or more serovars; seroconversion was detected in 28 cases. Percentage of 85.1% of the samples reactive on MAT corresponded to males, 39.4% corresponded to patients aged between 20 and 39 years old. The most common serovars found were Icterohaemorrhagiae, Andamana, Patoc, Tarassovi, Copenhageni, Hardjo and Australis. Concerning the samples that exhibited titers bigger than 800, serovar Icterohaemorrhagiae was also the most common, followed by Copenhageni, Andamana, Patoc, Tarassovi, Grippotyphosa and Canicola. In this study, 40% of the cases occurred to the metropolitan area, state capital and 34 neighboring towns. CONCLUSION: Our results show the possibly spreading serovars in Minas Gerais State and contribute to knowledge of human leptospirosis, aiming at improving the prevention, control of the disease, as well as the treatment of infected patients.

Panorama dos surtos de doença de transmissão alimentar (DTA) ocorridos em Minas Gerais, Brasil, no período de 2010 a 2014 / Panorama of outbreak foodborne disease occurring in Minas Gerais state, Brasil, the period of 2010 to 2014

A ocorrência de Doenças de Transmissão Alimentar (DTA), relevante problema de saúde pública, vem aumentando de modo significativo não só no Brasil, mas em diversos países. Com o propósito de descrever o perfil epidemiológico e microbiológico dos surtos de DTA ocorridos no estado de Minas Gerais, foi realizado um estudo descritivo e retrospectivo dos eventos de DTA investigados entre 2010 e 2014. Neste período foram analisadas 470 amostras de alimentos provenientes de 258 surtos. Nestes eventos foram registrados 4.662 adoecimentos, 659 hospitalizações e 3 vítimas fatais. A análise dos dados demonstrou que as residências foram o local de maior ocorrência dos surtos. Entretanto, a maior média de casos por local e a maior taxa de internação foram verificadas nos eventos festivos e nos refeitórios industriais, respectivamente. Dentre os micro-organismos isolados, Estafilococos Coagulase Positiva foi o agente de maior frequência (33,2%). No que se refere às categorias de alimentos envolvidas nos surtos, as preparações mistas foram o grupo mais frequente (35,2%).

Development of an amperometric immunosensor for detection of staphylococcal enterotoxin type A in cheese.

This paper reports a novel electrochemical immunosensor for the sensitive detection of staphylococcal enterotoxin A (SEA) based on self-assembly monolayer (SAM) and protein A immobilization on gold electrode. Three different methods of protein A immobilization were tested: physical adsorption, cross-linking using glutaraldehyde and covalent binding after activation with N-hydroxysuccinimide (NHS)/N-ethyl-N'-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) on cysteamine-modified gold electrode. The EDC/NHS method for protein A immobilization was selected to lead development of the biosensor. The coating steps of the surface modification were characterized by cyclic voltammetry and the biosensor response by chronoamperometry. The advantages of the immunosensor were exposed in its high sensitivity and specificity. The proposed amperometric immunosensor was successfully used for determination of SEA in contaminated and non-contaminated cheese samples with excellent responses.

A case study of a massive staphylococcal food poisoning incident.

In the summer of 1998, approximately 8000 individuals gathered to celebrate a Catholic priest's ordination in Minas Gerais, Brazil. Within hours of food consumption, 4000 patients experienced acute gastroenteritis, and approximately 2000 (50%) overwhelmed Emergency Departments of 26 local hospitals. Of the triaged patients, 396 ( approximately 20%) required subsequent admission, and of these patients, 81 ( approximately 20%) were admitted to intensive care units. A total of 16 ( approximately 20% of those admitted to the ICU) patients progressed on to develop irreversible multi-system shock and expired while hospitalized. The trace-back investigation implicated food preparers who were culture positive for enterotoxigenic Staphylococcus aureus as the source of contamination. This study provides information on the magnitude and severity of oral exposure to Staphylococcal enterotoxin.

An outbreak of staphylococcal food poisoning in the Municipality of Passos, MG, Brazil

An outbreak of staphylococcal food poisoning involving 42 people who had eaten a meal at a restaurant in the Municipality of Passos, Minas Gerais, Brazil, is reported. Thirty-one of the individuals became ill with vomiting, diarrhea and dizziness within 30 minutes after eating the meal. The foods suspected were: chicken pancake, rice, beans, tomato sauce and mashed chick-peas. Large numbers (> 2.0x10(8) CFU/g) of enterotoxigenic staphylococci were present in the chicken pancake. These strains produced enterotoxins A, B and D. Swabs from the nasal cavity and throat and from under the fingernails of food handlers were cultured for the detection of enterotoxigenic staphylococci carriers. Four out of five of them were healthy carriers of enterotoxin A, B, C and D producing Staphylococcus aureus at the sites cultured and one of them was also a nasal carrier of TSST-1 toxin producing S. aureus. These results indicate that the food handlers would have been the source of the food contamination

Surto de toxinfecçäo alimentar causado pela açäo simultânea de enterotoxina estafilocócica e Salmonella enteritidis - Estudo de caso / outbrak of food toxical infection caused by simultaneous action of Staphylococcal enterotoxin and Salonella Enteritidis

Infeçäo alimentar envolvendo dezesseis pessoas foi investigado em março degado em março de 1977 na cidade de Passos-MG. Quatorze 87,5(por cento), foram acometidas com os seguintes sintomas: náuseas, vômitos, cefaléia, febre, dores abdominais e diarréia. De acordo com a investigaçäo o alimento suspeito foi uma torta gelada, sem cobertura e sem recheio, servida como sobremesa. A análise do alimento revelou que o referido episódio foi causado pela açäo simultânea de enterotoxina estafilocócica C, D e Salmonella enteritidis

Salmonelas isoladas de queijos tipo "Coalho": caracterizaçäo sorológica e resistência a agentes antimicrobianos - Recife(PE) / Salmonella isolated from \"curd\" of cheese: sorological characterization and resistence to antimicrobial agents - Recife(PE)

Com o objetivo de isolar, identificar e avaliar a resistência antimicrobiana de linhagens de Salmonella, 107 amostras de queijo tipo "coalho" foram colhidas no período de janeiro a maio de 1997, no comércio varejista de Recife(PE). As amostras, obtidas de estabelecimentos comerciais que acondicionavam o produto em temperatura ambiente, variando entre 29,0 e 33,0§C eram transportadas em embalagens plásticas hermeticamente fechadas, sob refrigeraçäo por via aérea até Belo Horizonte (MG) onde eram prontamente analisadas pelo Serviço de Microbiologia de Alimentos da Fundaçäo Ezequiel Dias (FUNED). O isolamento e identificaçäo de Salmonella foram realizados segundo metodologia preconizada por VANDERZANT & SPLITTSTOESSER (1992). Das amostras analizadas, 8,41(por cento)(9/107) apresentaram-se positivas para Samonellas. Samonella I (011:-:1,6;018;6,7:K:-;3,10:y:-,6,7:-:enz;13,23:z:-); Samonella sp. Samonella enteritidis foi identificada individualmente em 11,11 (por cento) (1/9) das amostras. Apenas Samonella enterica subsp I (6,7:-:enz) apresentou frequência de 22,22 (por cento) de positividade (2/9). As linhagens isoladas apresentaram resistência frente a 37,5 (por cento) (6/16) dos produtos antimicrobianos testados: ampicilina, tetraciclina, cefotaxima, sulfametropina, trimetoprin e sulfazotrim. A sensibilidade foi observada em 62,5(por cento) (10/16), frente aos seguintes antimicrobianos: ciprofloxacina, tobramicina, ceftazidima, amoxacilina, polimixina B, gentamicina, cloranfenicol, amicacina, ofloxacina e cefoxitina

Enterotoxigenic staphylococci from food handlers working in an industrial kitchen in Belo Horizonte, MG (Brazil)

Cinquenta e cinco indivíduos säos, manipuladores de alimentos de uma cozinha industrial em Belo Horizonte, MG, foram examinados quanto a presença de estafilococos enterotoxigênicos. Trinta e dois (58,2 por cento) apresentaram-se portadores de S. aureus e 17 (30,9 por cento) de S. aureus enterotoxigênico, estes, assim distribuídos: 8 nasais, 9 de cavidade orofaríngea e 7 de leito subungueal. Onze manipuladores carrearam linhagens enterotoxigênicas em apenas um dos 3 sítios e um carreou linhagem produtora de enterotoxina B, concomitantemente em todos 3 sítios pesquisados. Quatro cepas se mostraram produtoras de enterotoxina A, 10 de enterotoxina B, 4 de enterotoxina C e 6 de enterotoxina A e B. Considerando-se que, 30,9 por cento dos manipuladores de cozinha industrial que produzia em 1992, em Belo Horizonte, 80.000 refeiçöes/dia, caracterizaram portadores de S. aureus enterotoxigênico, o resultado obtido pode ser considerado significativamente elevado

Intoxicaçäo por Staphylococcus aureus provocada por queijo "tipo Minas" / Staphylococcal food poisoning by cheese \"tipo Minas\"

Queijo "tipo Minas" padrão produzido de forma não industrial em uma fazenda do município de Itatiaiuçu, MG, apresentando 2.0x10elevado à sétima potência UFC de Staphylococcus aureus enterotoxigênico/g, provocou intoxicação em sete pessoas em Belo Horizonte, MG.