Occurrence, genetic diversity and resistance profiles of Salmonella enterica from Brazilian sausages collected at production facilities.

This study aimed to investigate the occurrence and the genetic diversity of Salmonella enterica subsp. enterica in sausages from Southern Brazil, evaluate virulence genes and determine the phenotypic and genotypic basis of antimicrobial and sanitizer resistance. Salmonella was detected in sausage samples with an overall prevalence of 5.5%. The prevalent serovars were S. Infantis and S. Rissen. Pulsed-field gel electrophoresis (PFGE) analysis yielded nine distinct PFGE profiles, and some of them were recurrently recovered in the same establishment on different dates. Among tested isolates, 28.5% showed resistance to at least one antimicrobial agent and a multidrug-resistance (MDR) profile was observed in 21.4%. Resistance occurred most frequently to ampicillin, sulfonamide, trimethoprim/sulfamethoxazole, and trimethoprim. Regarding the genotypic antimicrobial resistance profile, S. Schwarzengrund carried tet(B), strA, strB, and sul2 genes. Benzalkonium chloride and chlorhexidine were more effective than peracetic acid and sodium hypochlorite, showing lower minimum inhibitory concentration values. Six Salmonella serovars were found, demonstrating a potential risk of salmonellosis associated with consuming this food. Salmonella carrying virulence genes, MDR profile, and tolerance to sanitizers is a public health concern and a challenge for the food industry, suggesting that new strategies should be developed to control this pathogen. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-023-05809-w.

Salmonella Serovars Isolated from Poultry Breeding Flocks under the Brazilian Official Control Programme Between 2016 and 2018

The control of Salmonella in the poultry production chain combined with biosecurity measures is an important tool to maintain and guarantee the sanitary status of Brazilian flocks. The aim of this work was to compare official laboratory data on molecular typification of Salmonella isolates from poultry breeding flocks in different Brazilian states between 2016 and 2018 and identify the production category with the most positive flocks, in light of current legislation. Surveillance data of positive samples from the official Brazilian Salmonella Control Programme sent to Federal Agricultural Defence Laboratory of São Paulo (LFDA-SP) after molecular characterization were analysed. These data were subject to an exploratory study, undergoing a descriptive statistical analysis followed by the use of frequency and non-parametric hypothesis tests. Overall, 49 serovars were detected in poultry broiler-breeder and layer-breeder flocks. Salmonella ser. Heidelberg, Salmonella ser. Anatum, Salmonella ser. Newport, Salmonella ser. Schwarzengrund and Salmonella ser. Mbandaka were the five most common isolated serovars. The data shows that there is an opportunity to improve biosecurity measures in parent breeder flocks. A total of 16 serovars were identified in turkey-breeders. Salmonella ser. Anatum, Salmonella ser. Newport, Salmonella ser. Brandenburg, Salmonella ser. Litchfield, and Salmonella ser. Livingstone were the most common ones. The four official controlled serovars represented a small part of the isolated strains. These data demonstrate the importance of an official program in Brazil for Salmonella surveillance in breeder flocks combined with biosecurity measures.(AU)

Multidrug Resistance and Virulence Profiles of Salmonella Isolated from Swine Lymph Nodes.

Salmonella spp. is a foodborne pathogen present in the pork production chain, leading to potential contamination of end products and causing salmonellosis cases and outbreaks worldwide. The emergence of multidrug-resistant (MDR) Salmonella spp., especially isolates obtained from animal origin food, is a global concern. This study aimed to isolate Salmonella from swine mesenteric lymph nodes (MLN) and to characterize the virulence and antibiotic resistance profiles. MLN samples were obtained from a swine slaughterhouse and subjected to Salmonella spp. isolation. Ten MLN samples were positive and 29 isolates were identified based on PCR (invA and ompC) and serotyping: Derby, Cerro, and Give. Pulsed-field gel electrophoresis allowed to group the isolates based on their serotypes, resulting in three major clusters. All isolates presented the virulence-related genes pefA, sipA, sopB, spaN, and pagC. Relatively high numbers of Salmonella spp. were resistant to neomycin, polymyxin B, ciprofloxacin, tetracycline, and nalidixic acid. Furthermore, 25 isolates presented simultaneous resistance to three or more antibiotic classes, being characterized as MDR. The obtained results confirmed the relevance of swine as reservoirs of Salmonella spp. in the pork production chain and demonstrated the MDR profiles of isolates. Proper control and surveillance are required to avoid the contamination of end products.

Whole-genome sequencing analysis and CRISPR genotyping of rare antibiotic-resistant Salmonella enterica serovars isolated from food and related sources.

For decades, Salmonella Typhimurium and Salmonella Enteritidis have prevailed in several countries as agents of salmonellosis outbreaks. In Brazil, the largest exporter of poultry meat, relatively little attention has been paid to infrequent serovars. Here, we report the emergence and characterization of rare serovars isolated from food and related sources collected between 2014 and 2016 in Brazil. Twenty-two Salmonella enterica isolates were analyzed through the use of whole-genome sequencing (WGS) and clustered regularly interspaced short palindromic repeats (CRISPR) genotyping. These isolates were classified into 10 infrequent serovars, including S. Abony, S. Isangi, S. Rochdale, S. Saphra, S. Orion, S. Ouakam, S. Grumpensis, S. Carrau, S. Abaetetuba, and S. Idikan. The presence of six antimicrobial resistance (AMR) genes, qnrB19, blaCMY-2, tetA, aac(6')-Iaa, sul2 and fosA7, which encode resistance to quinolones, third-generation cephalosporin, tetracycline, aminoglycoside, sulfonamide and fosfomycin, respectively, were confirmed by WGS. All S. Isangi harbored qnrB19 with conserved genomic context across strains, while S. Abony harbored blaCMY-2. Twelve (54.5%) strains displayed chromosomal mutations in parC (Thr57→Ser). Most serovars were classified as independent lineages, except S. Abony and S. Abaetetuba, which phylogenetically nested with Salmonella strains from different countries. CRISPR analysis revealed that the spacer content was strongly correlated with serovar and multi-locus sequence type for all strains, independently confirming the observed phylogenetic patterns, and highlighting the value of CRISPR-based genotyping for Salmonella. These findings add valuable information to the epidemiology of S. enterica in Brazil, where the emergency of antibiotic-resistant Salmonella continues to evolve.

Antimicrobial Resistance in Nontyphoidal Salmonella Isolates from Human and Swine Sources in Brazil: A Systematic Review of the Past Three Decades.

Salmonella is the leading cause of foodborne illnesses worldwide. The widespread use of antimicrobials as prophylactic, therapeutic, and growth promoters in both livestock and human medicine has resulted in selective pressure regarding antimicrobial-resistant (AMR) bacteria. This systematic review summarizes phenotypic antimicrobial resistance profiles in Salmonella isolates from human and swine sources between 1990 and 2018 in Brazil. The 20 studies that matched the eligibility criteria-isolates from pigs and humans from Brazil, between 1990 and 2016, containing information on the number of Salmonella isolates, and applying the disk diffusion susceptibility method-were included. During the assessed period, Salmonella strains isolated from swine sources displayed the highest resistance rates for tetracycline (20.3%) and sulfonamides (17.4%). In contrast, human isolates displayed the highest resistance rates against ampicillin (19.8%) and tetracycline (17%). Salmonella Typhimurium was the most frequent AMR isolate from both swine and human sources, corresponding to 67% of all isolates. From 2001 to 2005, tetracycline and ampicillin were the top antimicrobial resistance compounds, and the most frequently detected in swine and human sources, respectively. A total of 63 and 58 multiple drug resistance profiles were identified in swine and human isolates, respectively. Antimicrobial resistance has decreased throughout the 1990-2016 period, except for gentamicin and nalidixic acid in swine and human isolates, respectively. The results indicate that Salmonella isolated from human and swine display resistance against clinically important antimicrobials, indicating that swine are possibly one of the main vectors for spreading human salmonellosis in Brazil.

Salmonella serovars in laying hen flocks and commercial table eggs from a region of São Paulo state, Brazil

Salmonella spp. is the main originator of human foodborne diseases worldwide and is mainly transmitted by food containing eggs. In Brazil, as a result of the lack of studies and data collection very little is known about the prevalence of Salmonella spp. in laying hen flocks and commercial table eggs. Consequently the present study was elaborated and aimed at generating data about Salmonella spp. in part of the Brazilian egg production chain. Eight flocks of day-old chicks, eight flocks of adult laying hens (four vaccinated with bacterin against Salmonella Enteritidis and four unvaccinated) and commercial table eggs from four supermarkets were examined. Salmonella spp. was isolated in 50 % of the newly hatched chicks, 25 % of the adult flocks and 1.5 % of egg samples examined. S. enterica subsp. enterica 4,12:r:-, S. Mbandaka, S. enterica subsp. enterica 6,7: z10:-, S. Enteritidis and S. Havana were the serovars isolated in birds. In commercial table-eggs S. Mbandaka, S. enterica subsp. enterica 6,7: z10:- and S. Braenderup were isolated. These results show that Salmonella spp. is present in laying hen flocks and consequently in eggs destined for human consumption. Probably, some of the Salmonella serovars are being introduced in egg farms by vertical via.(AU)

Salmonella serovars in laying hen flocks and commercial table eggs from a region of São Paulo state, Brazil

Salmonella spp. is the main originator of human foodborne diseases worldwide and is mainly transmitted by food containing eggs. In Brazil, as a result of the lack of studies and data collection very little is known about the prevalence of Salmonella spp. in laying hen flocks and commercial table eggs. Consequently the present study was elaborated and aimed at generating data about Salmonella spp. in part of the Brazilian egg production chain. Eight flocks of day-old chicks, eight flocks of adult laying hens (four vaccinated with bacterin against Salmonella Enteritidis and four unvaccinated) and commercial table eggs from four supermarkets were examined. Salmonella spp. was isolated in 50 % of the newly hatched chicks, 25 % of the adult flocks and 1.5 % of egg samples examined. S. enterica subsp. enterica 4,12:r:-, S. Mbandaka, S. enterica subsp. enterica 6,7: z10:-, S. Enteritidis and S. Havana were the serovars isolated in birds. In commercial table-eggs S. Mbandaka, S. enterica subsp. enterica 6,7: z10:- and S. Braenderup were isolated. These results show that Salmonella spp. is present in laying hen flocks and consequently in eggs destined for human consumption. Probably, some of the Salmonella serovars are being introduced in egg farms by vertical via.

Atividade antimicrobiana do óleo essencial de rizomas de açafrão (Curcuma longa L. ) e gengibre (Zingiber officinale Roscoe) frente a salmonelas entéricas isoladas de frango resfriado / Antimicrobial activity of essential oil from Curcuma longa and Zingiber officinale rhizomes against enteric Salmonella isolated from chicken

Objetivou-se com este trabalho identificar, quantificar os constituintes, e avaliar a atividade antibacteriana dos óleos essenciais extraídos de rizomas de açafrão (Curcuma longa L.) e gengibre (Zingiber officinale Roscoe) cultivados nas condições de Manaus/AM frente a 14 salmonelas entéricas isoladas de frango resfriado. A extração dos óleos essenciais foi realizada utilizando-se aparelho tipo Clevenger e a composição determinada por Cromatografia Gasosa acoplada a Espectrometria de Massas (CG-MS). A atividade antibacteriana foi realizada com o emprego de técnica de microdiluição em caldo. O óleo essencial de gengibre se mostrou expressivamente mais eficiente do que o óleo de açafrão, tanto em termos de ação bacteriostática (concentração inibitória mínima de 2500 a 5000 µg.mL-1) quanto bactericida (concentração bactericida mínima de 5000 a 10000 µg.mL-1) observando-se variação apenas em duas as amostras em termos de resistência a ação bactericida deste óleo. Assim, o óleo essencial de gengibre, representa uma alternativa para o controle de Salmonella enterica, entretanto, demais estudos abordando o sinergismo com alimentos são indicados.

The objective of this work was to identify, quantify constituents and evaluate the antibacterial activity of essential oils from rhizomes of turmeric (Curcuma longa L.) and ginger (Zingiber officinale Roscoe) grown under conditions of Manaus/AM front of enteric salmonella isolated from chilled poultry. The extraction of essential oils was performed using the Clevenger type apparatus and composition determined by Gas Chromatography coupled to Mass Spectrometry (GC-MS). The antibacterial activity was performed with the use of microdilution broth. The essential oil of ginger proved significantly more efficient than tumeric oil, both in terms of bacteriostatic action (minimum inhibitory concentration 2500-5000 mg µg mL-1) and bactericidal (minimum bactericidal concentration 5000-10000 mg µg mL-1) observing changes in only two samples in terms of resistance to bactericidal activity of this oil. Thus, the essential oil of ginger, is an alternative for the control of Salmonella enterica, however, other studies addressing the synergism with food are indicated.