Salmonella in Chicken and Pork Meat as a Likely Major Contributor to Foodborne Illness in Peru.

Nontyphoidal Salmonella is one of the major causes of self-limiting diarrheal disease and the most common foodborne pathogen worldwide. It is an important contributor to the burden of foodborne illness in South America, including Peru, where chicken and pork are important vehicles for Salmonella infection. Salmonella infections are underreported, particularly in low- and middle-income countries where concerted action tackling Salmonella along the chicken and pork chains, from primary production to retail, is urgently needed. To support and inform the implementation of new strategies to reduce Salmonella contamination of chicken and pork, this study describes the frequency and distribution of foodborne outbreaks attributed to Salmonella in Peru and evaluates the level of Salmonella in chicken and pork meat sold in markets of three regions of Peru. To that end, we analyzed historical reports of foodborne outbreaks, levels of Salmonella in chicken and pork sold in markets, and the number of mesophiles in the collected meat samples. As a result, the microbiological analysis reveals a widespread contamination of chicken (77.1%) and pork (26.8%) with Salmonella. It also pinpoints Salmonella as the causative agent in nearly half of the outbreaks (47.0%) where the potential origin is identified over a 11-year period with chicken, mayonnaise, and pork being the most likely food vehicles. These results suggest that Salmonella is a major contributor to foodborne illness in Peru and that the monitoring of mesophiles could be a good strategy for surveillance, generating data to support source attribution studies and ultimately evidence-informed policies.

Development of recombinant subunit vaccine targeting InvH protein of Salmonella Typhimurium and evaluation of its immunoprotective efficacy against salmonellosis.

Salmonella Typhimurium is the most prevalent non-host specific Salmonella serovars and a major concern for both human and animal health systems worldwide contributing to significant economic loss. Type 3 secretion system (T3SS) of Salmonella plays an important role in bacterial adherence and entry into the host epithelial cells. The product of invH gene of Salmonella is an important component of the needle complex of the type 3 secretion system. Hence, the present study was undertaken to clone and express the 15 kDa InvH surface protein of Salmonella Typhimurium in an E. coli host and to evaluate its immune potency in mice. The purified recombinant InvH (r-InvH) protein provoked a significant (p < 0.01) rise in IgG in the inoculated mice. The immunized mice were completely (100%) protected against the challenge dose of 107.5 LD50, while protection against challenge with the same dose of heterologous serovars was 90%. The bacterin-vaccinated group showed homologous protection of 60% against all three serovars. Findings in this study suggest the potential of the r-InvH protein of S. Typhimurium as an effective vaccine candidate against Salmonella infections.

Genotyping and antimicrobial resistance profiles of chicken originated Salmonella Enteritidis isolates.

Salmonellosis is a common foodborne zoonosis worldwide. The most common Salmonella serovar in humans is Salmonella enterica subsp. enterica serovar Enteritidis (50.3%) in the world. The main transmission route for S. Enteritidis is consumption of contaminated poultry products. Therefore, it is important to determine the diversity and spread of chicken-originated S. Enteritidis isolates in order to monitor and control salmonellosis. Pulsed-field gel electrophoresis (PFGE) and multiple locus variable number of tandem repeats analysis (MLVA) are frequently used for typing of S. Enteritidis isolates. This study aimed to determine the antimicrobial resistance (AMR) profiles and MLVA and PFGE genotypes of chicken-originated S. Enteritidis isolates. A total of 200 S. Enteritidis isolated from chicken broiler, layer, and breeder flocks from different locations in Turkey were investigated by Kirby-Bauer disk diffusion method, PFGE, and MLVA. The AMR test indicated that 57% of the S. Enteritidis isolates were susceptible to all antimicrobials, while 39% were resistant to at least one antimicrobial. The highest resistance (25%) was against ampicillin. Multi-drug resistance rate was low (21%) and mostly from broiler flocks (93%). All isolates were genotyped into 32 different PFGE genotypes (PT) and 34 different MLVA genotypes (MT). The dominant genotypes were PT6 (12.5%) and MT22 (50%). In specific sample groups, there was a correlation between genotypes, breeding type, geographic location, and isolation years of the isolates. There was no significant difference in the discrimination power of PFGE and MLVA. However, MLVA was more suitable for large sample groups and routine genotyping because it was easier, quicker, and less labor-intensive to use.

Epidemiological and clinicopathological findings in 15 fatal outbreaks of salmonellosis in dairy calves and virulence genes in the causative Salmonella enterica Typhimurium and Dublin strains.

Salmonella enterica is a major food-borne pathogen that affects cattle-rearing systems worldwide. Little information is available on the epidemiology and pathology of salmonellosis and the virulence genes (VGs) carried by Salmonella in spontaneous outbreaks in cattle. We describe epidemiological findings in 15 fatal outbreaks of salmonellosis in Uruguayan dairy farms and the age, clinical signs, and pathology in 20 affected calves. We also describe the serotypes and frequencies of 17 VGs in the causative Salmonella strains and explore their associations with epidemiological, clinical, and pathological findings. Salmonella Typhimurium and Dublin were identified in 11/15 and 4/15 outbreaks, respectively. The most frequent reason for consultation was digestive disease (8 outbreaks caused by S. Typhimurium), followed by sudden death (4 outbreaks, 3 caused by S. Dublin). Morbidity, mortality, and lethality ranged 4.8-100%, 3.8-78.9%, and 10-100%, without significant differences between serotypes. Diarrhea, the most common clinical sign (14 cases), was associated with the Typhimurium serotype (OR = 26.95), especially in ≤ 30-day-old calves with fibrinous enteritis as the main autopsy finding. The Dublin serotype affected ≥ 50-day-old calves and was associated with fibrinosuppurative splenitis (p = 0.01) and tubulointerstitial nephritis (OR = 48.95). The chances of the Dublin serotype increased significantly with age. There was low variability of VG across serotypes. The pefA gene was associated with the Typhimurium serotype (OR = 21.95), macroscopic enteritis (p = 0.03), and microscopic fibrinosuppurative splenitis (p = 0.04). Understanding the epidemiology, pathology, and virulence of S. enterica at the farm level is key to delineating prevention and control strategies to mitigate its impact on animal and human health.

Phylogenetic analyses of Salmonella detected along the broiler production chain in Trinidad and Tobago.

This study was conducted to determine the phylogenies of Salmonella strains isolated from cross-sectional studies conducted at hatcheries, broiler farms, processing plants, and retail outlets (broiler production chain) in Trinidad and Tobago over 4 yr (2016-2019). Whole-genome sequencing (WGS) was used to characterize Salmonella isolates. Core genome phylogenies of 8 serovars of public health significance were analyzed for similarities in origin and relatedness. In addition, Salmonella strains isolated from human salmonellosis cases in Trinidad were analyzed for their relatedness to the isolates detected along the broiler production chain. The common source of these isolates of diverse serovars within farms, within processing plants, between processing plants and retail outlets, and among farm-processing plant-retail outlet continuum was well-supported (bootstrap value >70%) by the core genome phylogenies for the respective serovars. Also, genome analyses revealed clustering of Salmonella serovars of regional (intra-Caribbean) and international (extra-Caribbean) origin. Similarly, strains of S. Enteritidis and S. Infantis isolated from human clinical salmonellosis in 2019 from Trinidad and Tobago clustered with our processing plant isolates recovered in 2018. This study is the first phylogenetic analysis of Salmonella isolates using WGS from the broiler industry in the Caribbean region. The use of WGS confirmed the genetic relatedness and transmission of Salmonella serovars contaminating chickens in broiler processing, and retailing in the country, with zoonotic and food safety implications for humans.

Genotypic and phenotypic quantitative microbial risk assessment model of human salmonellosis related to the consumption of chicken meat in the central region of Mexico.

Chicken meat is often associated withSalmonella entericacontamination worldwide. This study proposes a risk assessment model for human salmonellosis linked to the domestic consumption of chicken meat in the central region of Mexico, incorporating genotypic and phenotypic data. SixS. entericagroups were used, considering the presence of specific virulence genes and multidrug resistance (MDR). Sixteen exposure scenarios were established considering retail point (RP1 = fresh market/butcher shop; RP2 = mini-super/supermarket), transportation, home storage, cooking, and cross-contamination. The model predicted a mean annual salmonellosis cases of 66,754 due to chicken consumption (CI95% 10775-231606). The mean probability of illness (Pill) among the exposure scenarios ranged from 2.5 × 10-9 to 3.7 × 10-6, 7.7 × 10-8 to 1.1 × 10-4, and 6.7 × 10-4 to 7.8 × 10-2 for low, moderate, and high virulence groups. Exposure scenarios with the highest Pill were not responsible for most cases due to their low frequency of occurrence. The high virulence/ MDR group was responsible for most cases (66.5 %), despite the low S. enterica prevalence (RP1 0.5 % and RP2 5.0 %). The years lost due to disability (YLD) value for MDR was 2.6 × higher than for non-MDR. Spearman rank showed that the inputs with higher influence on the variability of salmonellosis depended on the type of exposure scenario. For example, the cooking temperature and time had the most significant influence in the scenarios where S. enterica can survive after cooking. Including the microbial genotypic and phenotypic characteristics in risk assessment modeling highlights the importance of focusing on high-virulent and MDR strains, which are not the most frequent but represent the highest public health risk.

Salmonella enterica in soybean production chain: Occurrence, characterization, and survival during soybean storage.

This study aimed to determine Salmonella enterica occurrence along the soybean meal production chain (raw material, in-processing samples, final products, and in the environment of five processing plants), characterize the isolates, and assess the survival of Salmonella Senftenberg 775W in soybeans stored under different temperature conditions. Among 713 samples analyzed, 12.9% (n = 92) were positive for Salmonella enterica. Dust collected inside and outside processing plants (n = 148) comprised the samples with the highest positivity for Salmonella enterica, 47.3%. The occurrence of Salmonella enterica varied among the different processing plants. Twenty-nine (n = 29) Salmonella serotypes were isolated, with S. Mbandaka as the most frequent serotype, whereas S. Typhimurium was mainly linked to final product samples (soybean meal). S. Senftenberg 775W did not survive for a long time in soybean stored at 20-37 °C, but at 20 °C, cells were viable for more than 60 days. This study suggests that soybean meal may harbor Salmonella serotypes related to foodborne disease outbreaks in humans and can be responsible for Salmonella introduction into livestock and, consequently, in foods of animal origin. This study provides crucial data on contamination pathways of Salmonella in the soybean production chain, contributing to the understanding of Salmonella epidemiology which is strategic for the development of preventive and control measures to reduce the burden of salmonellosis linked to products of animal origin.

Salmonella spp. in low water activity food: Occurrence, survival mechanisms, and thermoresistance.

The occurrence of disease outbreaks involving low-water-activity (aw ) foods has gained increased prominence due in part to the fact that reducing free water in these foods is normally a measure that controls the growth and multiplication of pathogenic microorganisms. Salmonella, one of the main bacteria involved in these outbreaks, represents a major public health problem worldwide and in Brazil, which highlights the importance of good manufacturing and handling practices for food quality. The virulence of this pathogen, associated with its high ability to persist in the environment, makes Salmonella one of the main challenges for the food industry. The objectives of this article are to present the general characteristics, virulence, thermoresistance, control, and relevance of Salmonella in foodborne diseases, and describe the so-called low-water-activity foods and the salmonellosis outbreaks involving them.

Nontyphoidal Salmonella in Food from Latin America: A Systematic Review.

In Latin America, nontyphoidal Salmonella (NTS) is one of the most important etiological agents of foodborne infections; it can survive in soil, water, and food even after processing. Here, we aimed to perform a systematic review by collecting data on the prevalence, serotypes, and antimicrobial resistance (AMR) of NTS isolated from different food products in Latin America, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Out of 1766 studies screened, 244 reports from 13 Latin American countries were eligible. Among these, 182 reported NTS prevalence, 87 reported NTS serotypes, and 83 reported serotypes with AMR patterns. The NTS prevalence ranged from 0.005% to 93.3%, regardless of country and food. Meat showed the highest NTS prevalence. Enteritidis, Typhimurium, and Derby were the most frequently observed serotypes in different food products. The serotypes Enteritidis, Typhimurium, and Infantis, isolated from animal products, showed the highest AMR rate. The presence of NTS in fruits and vegetables, which are generally consumed raw or as ready-to-eat food, indicates a high risk of salmonellosis from consuming these foods. Thus, the reduction of this pathogen in the food chain requires a One Health approach, involving good agricultural and manufacturing practices, low antimicrobial use, and proper waste management.

Retrospective whole-genome comparison of Salmonella enterica serovar Enteritidis from foodborne outbreaks in Southern Brazil.

Salmonella enterica serovar Enteritidis is frequently isolated from animal-source foods associated with human salmonellosis outbreaks. This serovar was spread to animal (mainly poultry) farms worldwide in the 1980s, and it is still detected in foods produced in many countries, including Brazil. The present study reports a retrospective genome-wide comparison of S. Enteritidis from foodborne outbreaks in Southern Brazil in the last two decades. Fifty-two S. Enteritidis isolates were obtained from foodborne outbreaks occurring in different cities of the Brazilian southernmost State, Rio Grande do Sul (RS), from 2003 to 2015. Whole-genome sequences (WGS) from these isolates were obtained and comparatively analyzed with 65 additional genomes from NCBI. Phylogenetic and Bayesian analyses were performed to study temporal evolution. Genes related to antibiotic resistance and virulence were also evaluated. The results demonstrated that all S. Enteritidis isolates from Southern Brazil clustered in the global epidemic clade disseminated worldwide originally in the 1980s. Temporal analysis demonstrated that all Brazilian isolates had a tMRCA (time to most recent common ancestor) in 1986 with an effective population size (Ne) increase soon after until 1992, then becoming constant up to now. In Southern Brazil, there was a significant decrease in the spreading of S. Enteritidis in the last decade. In addition, three antibiotic resistance genes were detected in all isolates: aac(6')-Iaa, mdfA, and tet(34). These results demonstrate the high frequency of one only specific S. Enteritidis lineage (global epidemic clade) in foodborne outbreaks from Southern Brazil in the last two decades.

Modeling Salmonella spp. inactivation in chicken meat subjected to isothermal and non-isothermal temperature profiles.

Salmonella genus has foodborne pathogen species commonly involved in many outbreaks related to the consumption of chicken meat. Many studies have aimed to model bacterial inactivation as a function of the temperature. Due to the large heterogeneity of the results, a unified description of Salmonella spp. inactivation behavior is hard to establish. In the current study, by evaluating the root mean square errors, mean absolute deviation, and Akaike and Bayesian information criteria, the double Weibull model was considered the most accurate primary model to fit 61 datasets of Salmonella inactivation in chicken meat. Results can be interpreted as if the bacterial population is divided into two subpopulations consisting of one more resistant (2.3% of the total population) and one more sensitive to thermal stress (97.7% of the total population). The thermal sensitivity of the bacteria depends on the fat content of the chicken meat. From an adapted version of the Bigelow secondary model including both temperature and fat content, 90% of the Salmonella population can be inactivated after heating at 60 °C of chicken breast, thigh muscles, wings, and skin during approximately 2.5, 5.0, 9.5, and 57.4 min, respectively. The resulting model was applied to four different non-isothermal temperature profiles regarding Salmonella growth in chicken meat. Model performance for the non-isothermal profiles was evaluated by the acceptable prediction zone concept. Results showed that >80% of the predictions fell in the acceptable prediction zone when the temperature changes smoothly at temperature rates lower than 20 °C/min. Results obtained can be used in risk assessment models regarding contamination with Salmonella spp. in chicken parts with different fat contents.

An outbreak of Salmonella enterica subsp. enterica serovar Give associated with foodborne illness in the department of Vichada, Colombia, 2015 / Brote de Salmonella enterica subsp. enterica serovar Give asociado con enfermedad transmitida por alimentos en Vichada, Colombia, 2015.

Introduction: Salmonella enterica subsp. enterica serovar Give is found in ruminants, pigs, poultry, and aquatic environments, but rarely in humans. In Colombia, this serotype was ranked 11th. in the laboratory surveillance of acute diarrheal disease between 2000 and 2013. Objective: To characterize phenotypic and genotypic isolates of Salmonella related to an outbreak of foodborne Illness in the department Vichada in the fifth epidemiological week of 2015. Materials and methods: Following the Instituto Nacional de Salud method, we tested 37 fecal samples for Salmonella spp. while the sample of canned sardines was processed according to the ISO 6579:2002 Cor.1:2004 standard. The isolates were confirmed by serology and/or real-time PCR, antimicrobial susceptibility tests, and pulsed-field gel electrophoresis with the XbaI and BlnI enzymes. Results: All human isolates (11) and that from food (1) were identified as S. Give. The food isolate exhibited tetracycline resistance. PFGE analysis with XbaI grouped ten isolates from samples of human origin in pattern COIN15JEXX01.0005 and the remaining isolates in COIN15JEXX01.0006 with 96.3% similarity. All isolates were confirmed with the BlnI enzyme, and four (three human isolates and the one from food) were matched to the pattern COIN15JEXA26.002 with 95.65% similarity. Conclusion: Our study confirmed that canned sardines were related to the transmission of S. Give in the outbreak, which is the third one caused by this serotype in Colombia.

Introducción. Salmonella enterica subsp. enterica serovar Give se encuentra en mamíferos rumiantes, cerdos, aves y ambientes acuáticos, pero rara vez en humanos. En Colombia este serotipo ocupó el decimoprimer lugar en frecuencia en la vigilancia por laboratorio de la enfermedad diarreica aguda entre el 2000 y el 2013. Objetivo. Caracterizar el fenotipo y el genotipo de S. Give en aislamientos relacionados con un brote de enfermedad transmitida por alimentos en el departamento de Vichada en la quinta semana epidemiológica del 2015. Materiales y métodos. Se buscó Salmonella spp. en 37 muestras de materia fecal con el método de estudio del Instituto Nacional de Salud. La muestra de sardinas enlatadas fue procesada según la norma ISO6579:2002 Cor.1:2004. Se determinó el serotipo en los aislamientos confirmados mediante serología o PCR en tiempo real, y se hicieron pruebas de sensibilidad a antimicrobianos y electroforesis en gel de campo pulsado con las enzimas Xbal y BlnI. Resultados. Todos los aislamientos de origen humano (11) y el aislamiento del alimento (1), se identificaron como S. Give y este último presentó resistencia a la tetraciclina. El análisis por PFGE-XbaI agrupó bajo el patrón COIN15JEXX01.0005 diez aislamientos de origen humano y a los restantes bajo el COIN15JEXX01.0006, con un 96,3 % de similitud. Los resultados de todos los aislamientos se confirmaron con la enzima BlnI; cuatro de ellos (tres humanos y el del alimento) se agruparon bajo el patrón COIN15JEXA26.002, con un porcentaje de similitud del 95,65 %. Conclusión. El estudio confirmó que las sardinas enlatadas se relacionaron con la transmisión de S. Give en el brote, que es el tercero ocasionado por este serotipo en Colombia.

Development and characterization of a carvacrol nanoemulsion and evaluation of its antimicrobial activity against selected food-related pathogens.

Carvacrol has been recognized as an efficient growth inhibitor of food pathogens. However, carvacrol oil is poorly water-soluble and can be oxidized, decomposed or evaporated when exposed to the air, light, or heat. To overcome these limitations, a carvacrol nanoemulsion was developed and its antimicrobial activity against food pathogens evaluated in this study. The nanoemulsion containing 3% carvacrol oil, 9% surfactants (HLB 11) and 88% water, presented good stability over a period of 90 days. In general, the carvacrol nanoemulsion (MIC: 256 µg ml-1 for E. coli and Salmonella spp., 128 µg ml-1 for Staphylococcus aureus and Pseudomonas aeruginosa) exhibited improved antimicrobial activity compared to the free oil. The carvacrol nanoemulsion additionally displayed bactericidal activity against Escherichia coli, P. aeruginosa and Salmonella spp. Therefore, the results of this study indicated that carvacrol oil nanoemulsions can potentially be incorporated into food formulations, wherein their efficacy for the prevention and control of microbial growth could be evaluated.

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.

Probiotic Lactobacilli Improved Growth Performance and Attenuated Salmonella Typhimurium Infection Via Jak/Stat Signaling in Broilers

This study aimed to investigate the effect of Lactobacillus plantarum DPP8 and Lactobacillus acidophilus C7282 in feed supplementation on growth performance, Salmonella invasion, inflammation, and mediating signaling in broilers infected with Salmonella Typhimurium (S. Typhimurium). A total of 240 broilers at day old were randomly allocated into four groups, orally infected with S. Typhimurium and supplemented with individual or combined Lactobacilli DPP8 and C7282 at doses of 0 (control), 1010 (individual), or 2.0 × 1010 (combination) cfu/kg of diet for 21 d. The results showed that supplementing Lactobacilli improved (p 0.05) feed intake and body weight gain and decreased (p 0.05) S. Typhimurium load in the caecum, harder gland, spleen and bursa of Fabricius. Also, the supplements decreased (p 0.05) interleukin (1/2/4), tumor necrosis factor and interferon in the serum, enhanced (p 0.05) interleukin 10, and downregulated gene expressions of inflammatory mediators including Janus kinase (Jak2/3), signal transducer and activator of transcription protein (STAT3/4/5/6) in the intestinal mucosa. In contrast, diets containing DPP8 exhibited greater effects on the inhibition of the pathogen and inflammatory response than C7282. The obtained data suggest that Lactobacilli C7282 and DPP8 can be used as feed additives to inhibit colonization and translocation of S. Typhimurium and inflammatory responses via downregulating Jak/STAT signaling in broilers.(AU)

Probiotic Lactobacilli Improved Growth Performance and Attenuated Salmonella Typhimurium Infection Via Jak/Stat Signaling in Broilers

This study aimed to investigate the effect of Lactobacillus plantarum DPP8 and Lactobacillus acidophilus C7282 in feed supplementation on growth performance, Salmonella invasion, inflammation, and mediating signaling in broilers infected with Salmonella Typhimurium (S. Typhimurium). A total of 240 broilers at day old were randomly allocated into four groups, orally infected with S. Typhimurium and supplemented with individual or combined Lactobacilli DPP8 and C7282 at doses of 0 (control), 1010 (individual), or 2.0 × 1010 (combination) cfu/kg of diet for 21 d. The results showed that supplementing Lactobacilli improved (p 0.05) feed intake and body weight gain and decreased (p 0.05) S. Typhimurium load in the caecum, harder gland, spleen and bursa of Fabricius. Also, the supplements decreased (p 0.05) interleukin (1/2/4), tumor necrosis factor and interferon in the serum, enhanced (p 0.05) interleukin 10, and downregulated gene expressions of inflammatory mediators including Janus kinase (Jak2/3), signal transducer and activator of transcription protein (STAT3/4/5/6) in the intestinal mucosa. In contrast, diets containing DPP8 exhibited greater effects on the inhibition of the pathogen and inflammatory response than C7282. The obtained data suggest that Lactobacilli C7282 and DPP8 can be used as feed additives to inhibit colonization and translocation of S. Typhimurium and inflammatory responses via downregulating Jak/STAT signaling in broilers.

Phylogenetic structure of Salmonella Enteritidis provides context for a foodborne outbreak in Peru.

Salmonella Enteritidis, an important foodborne zoonosis, has a dramatically increased number of cases around the world. To explore the phylogenetic structure of Peruvian Salmonella Enteritidis strains and their relationship with an outbreak occurred in 2018, we analyzed a comprehensive strains of S. Enteritidis received by the National Institute of Health during the period 2000-2018. A total of 180 strains were characterized by microbiological procedures, serotyping and whole genome sequencing. Based on genome sequences annotated, virulence factors and accessory genes were identified. Phylogenetic and population structure analysis were also analyzed based on SNPs. The phylogenetic analysis grouped the genomes into two well-supported clades that were consistent with population structure analysis. The clinical and food strains corresponding to the outbreak were included in the same cluster, which presented the sdhA gene, related to the increase of the virulence of this pathogen. The phylogenetic relationship of Peruvian S. Enteritidis suggests the presence of four S. enteritidis population with high epidemiological importance.

Contaminação por Salmonella spp. durante o processamento de aves em abatedouros frigoríficos / Salmonella spp. contamination during poultry processing in slaughterhouses

A carne de aves e seus derivados estão entre os principais alimentos incriminados nos surtos de doenças veiculadas por alimentos (DVA) devido ao risco de veiculação de Salmonella spp. O controle é complexo porque existem inúmeras vias pelas quais essa bactéria pode contaminar a carne de aves e derivados, com várias possibilidades ao longo da cadeia produtiva. Falhas nas condições de manejo durante a criação de frangos de corte e nos procedimentos higiênicosanitários durante as operações de abate e manipulação das carcaças influenciam na contaminação por esse microrganismo nas indústrias. Abatedouros frigoríficos de aves são altamente automatizados e, apesar dos avanços tecnológicos, a carne de frango ainda é passível de contaminação, uma vez que lotes negativos podem se tornar positivos para Salmonella spp. devido a contaminação cruzada provocada por lotes infectados abatidos no mesmo dia ou devido à utilização de equipamentos e utensílios compartilhados. O extravasamento de conteúdo gastrointestinal durante a evisceração é a principal fonte de contaminação das carcaças por Salmonella spp. nos abatedouros. Na presente revisão, foram abordados aspectos gerais sobre o gênero Salmonella spp., com ênfase nas etapas do processamento de aves que propiciam contaminação de carcaças e nas respectivas estratégias que visam à mitigação do risco de veiculação desse microrganismo, considerando também a legislação pertinente.

Poultry meat and its derivatives are the main food involved in foodborne outbreaks due to the risk of transmitting Salmonella spp. The control is complex because there are several routes in which this bacterium can contaminate poultry meat, with several possibilities along the production chain. Failures in handling conditions during the rearing of broilers and in hygienic-sanitary procedures during slaughter steps and handling of carcasses in industries influence the contamination by this microorganism. Poultry slaughterhouses are highly automated and, despite technological advances, poultry meat is still susceptible to contamination mainly due the fact that negative animals can become contaminated with Salmonella spp. due cross contamination with infected animals when slaughtered at the same day or due the use of contaminated equipment and utensils. The extravasation of gastrointestinal content during evisceration is the main source of contamination of carcasses with Salmonella spp. in poultry slaughterhouses. In this review, general aspects about the genus Salmonella spp. were addressed, with emphasis on the stages of poultry processing that allow contamination of carcasses and the respective strategies used to mitigate the risk of transmitting this microorganism considering the relevant legislation.

Antimicrobial Resistance in Salmonella Serovars Isolated From an Egg-Producing Region in Brazil

Fowl paratyphoid infections are caused by different Salmonella serovars that can affect a wide range of hosts. Due to its complex epidemiology, Salmonella serovar identification is crucial for the development and implementation of monitoring and control programs in poultry farms. Moreover, the characterization of the antimicrobial resistance profiles of Salmonella strains isolated from livestock is relevant to public health because they are a common causative agent of foodborne diseases. The objective of this study was to investigate the presence of Salmonella spp. and to identify the antimicrobial resistance profiles of strains isolated in the midwestern region of São Paulo state, which accounts for the highest production of table eggs in Brazil. For this purpose, 2008 fecal samples were collected on 151 commercial layer farms and submitted to microbiological analyses. Twenty-two serovars were isolated from 80 (52.9%) farms, among which S. Mbandaka and S. Braenderup were the most prevalent. All isolates expressed resistance to at least one of the 23 antimicrobials tested, and the highest resistance rates were determined against streptomycin (93.5%) and sulfonamide (84.6%). Moreover, multidrug resistance was observed in 41% of the isolates and the maximum drug resistance profile was against ten different antimicrobials. Therefore, the identification of Salmonella serovars in poultry production provides epidemiological knowledge to develop prevention and control measures in order to ensure poultry health and to prevent human infection by multiresistant strains.(AU)

Antimicrobial Resistance in Salmonella Serovars Isolated From an Egg-Producing Region in Brazil

Fowl paratyphoid infections are caused by different Salmonella serovars that can affect a wide range of hosts. Due to its complex epidemiology, Salmonella serovar identification is crucial for the development and implementation of monitoring and control programs in poultry farms. Moreover, the characterization of the antimicrobial resistance profiles of Salmonella strains isolated from livestock is relevant to public health because they are a common causative agent of foodborne diseases. The objective of this study was to investigate the presence of Salmonella spp. and to identify the antimicrobial resistance profiles of strains isolated in the midwestern region of São Paulo state, which accounts for the highest production of table eggs in Brazil. For this purpose, 2008 fecal samples were collected on 151 commercial layer farms and submitted to microbiological analyses. Twenty-two serovars were isolated from 80 (52.9%) farms, among which S. Mbandaka and S. Braenderup were the most prevalent. All isolates expressed resistance to at least one of the 23 antimicrobials tested, and the highest resistance rates were determined against streptomycin (93.5%) and sulfonamide (84.6%). Moreover, multidrug resistance was observed in 41% of the isolates and the maximum drug resistance profile was against ten different antimicrobials. Therefore, the identification of Salmonella serovars in poultry production provides epidemiological knowledge to develop prevention and control measures in order to ensure poultry health and to prevent human infection by multiresistant strains.