Multi-virulence of Campylobacter jejuni carried by chicken meat in Brazil.

Campylobacter jejuni is the most frequent cause of bacterial gastroenteritis; therefore, the characteristics of its epidemiology must be continuously investigated to support possible mitigating measures. This is particularly important when evaluating representative strains from the world's leading chicken meat exporter, Brazil. We evaluated a panel of 14 virulence genes in 359 strains of C. jejuni isolated from chilled broiler carcasses in Brazil. The genes were classified into five virulence categories (B: biofilm/motility; SS: secretion/cytotoxicity system; CI: invasion/colonization; GB: Guillain-Barré; and AE: adaptation to stress). The percentage of strains with stress adaptation genes (86.07%) indicates the ability to survive in unfavorable environments; in addition, the strains showed a risk of causing infections in humans due to the frequency of the hcp gene (97.77%). Genes related to Guillain-Barre syndrome (GBS) in 77.44% of strains are an additional concern, which must be monitored. The gene panel showed the presence of 124 virulence profiles. Individual analyses by carcass, slaughter establishment, and municipalities in which they were located showed high index variabilities (I.Var.) of 0.82, 0.87, and 0.78, respectively. Georeferencing indicated the state of Paraná as a hotspot for virulent strains. Higher levels of isolation and multi-virulence were identified in the summer, which is hot and humid in Brazil. Together, our results showed that the studied strains are a potential danger to public health and that there is an urgent need for their surveillance and the adoption of control measures, especially in the state of Paraná.

Salmonella enterica Serovar Minnesota Biofilms, Susceptibility to Biocides, and Molecular Characterization.

The presence of virulence genes, phylogenetic relationships, biofilm formation index (BFI), and ultrastructure in S. Minnesota at different temperatures (4, 25, and 36 °C) were analyzed. In addition, the ability of biocidal agents (chlorhexidine1%, sodium hypochlorite 1%, and peracetic acid 0.8%) to inhibit biofilms formed by 20 strains isolated from broiler slaughter plants from two Brazilian companies in 2009, 2010, and 2014 was determined. The presence of specific genes was evaluated by PCR and phylogeny between strains by pulsed-field gel electrophoresis. The BFI was determined using tryptone soy broth with 5% of chicken juice, and its structure was observed by scanning electron microscopy. The presence of specific genes indicated that S. Minnesota has the potential to cause disease in humans, adapting to adverse conditions. Temperatures of 25 and 36 °C favored biofilm formation, although at 4 °C, there was still biomass that could contaminate the final product. Tolerance to all biocides was identified in 12/20 (60%), representing a real risk of adaptation mechanisms development, especially regarding to resistance to sodium hypochlorite. Phylogenetic analysis indicated cross-contamination and spread among companies, which was probably related to biofilms formation. Results show the necessity of attention to this serovar considering its resistance to sodium hypochlorite, including the need for rigorous control, adopting low temperatures to prevent biofilms formation in the poultry industry.

Microbiological assessment at slaughter of chicken carcasses from commercial, backyard and semi-backyard production systems.

INTRODUCTION: Smaller scale, alternative, chicken production systems are gaining popularity globally. However, this brings public health and market confidence concerns, especially where there are no established standards of production. The aim of this study was to carry out a microbiological analysis of chicken carcasses from the commercial, backyard and semi-backyard production systems, slaughtered in the same slaughterhouse. METHODOLOGY: Samples of 102 chicken carcasses were taken in two steps of the slaughter (A: after bleeding; and B: after chiller tank) and were subjected to aerobic mesophilic, coliforms at 35 °C and coliforms at 45 °C counts, and Salmonella spp. detection. Salmonella spp. isolates were subjected to antimicrobial resistance analysis. RESULTS: At slaughter step A, carcasses from the backyard system had less contamination than carcasses from the commercial system, with a difference of 0.7 log10 CFU/mL. Salmonella was identified in carcasses of all production systems and in both slaughter steps. Nine chicken carcasses were positive for Salmonella and no significant difference was observed in the occurrence of Salmonella amongst the carcasses from different production systems. Two Salmonella isolates, that presented the highest resistance profiles (one isolate was resistant to eight and the other to six out of ten tested antibiotics), were identified on carcasses from the semi-backyard system. CONCLUSIONS: Carcasses from the backyard system had a lower microbial count at the initial step of the slaughter process than the commercial production system. In addition, greater resistance to antimicrobials was observed in Salmonella isolates from semi-backyard system.

First Report of Genetic Variability of Erysipelothrix sp. Strain 2 in Turkeys Associated to Vero Cells Morphometric Alteration.

Erysipelas is a disease caused by the Erysipelothrix genus, whose main species is the E. rhusiopathiae, the causative agent of animal erysipelas and human erysipeloid. We isolated Erysipelothrix sp. strain 2 (ES2) from turkey's organs during an outbreak in Brazilian commercial and breeder flocks with sepsis and high mortality levels. We studied 18 flocks, accounting for 182 samples, being eight flocks (84 samples) as ES2 positive with individuals demonstrating clinical symptoms and high mortality. We obtained the genetic variability of 19 samples with PFGE and found two clones, both from the same flock but different samples, and two clusters. Interestingly, we found 15 strains with high genetic variability among and within flocks. We have found a positive association between the proximity of ES2 positive turkey flocks and commercial swine sites through epidemiological analysis. We infected Vero cells with two different isolates and three distinct concentrations of ES2. After performing the morphometry, we recorded enlargement of the nucleus and nucleolus. Moreover, we performed fluorescence assays that resulted in apoptotic and necrotic cells. We demonstrated that ES2 could multiply in the extracellular medium and invade and survive inside Vero cells. For the first time, our finds show that ES2 may have similar behavior as E. rhusiopathiae as a facultative intracellular microorganism, which may represent a hazard for humans.

Características de virulência de Salmonella Heidelberg isoladas na cadeia avícola brasileira / Virulence characteristics of Salmonella Heidelberg isolated in the Brazilian poultry chain

S. Heidelberg é frequentemente isolada em produtos avícolas e associada a infecções alimentares humanas. Objetivou-se determinar a presença de genes de virulência em 62 cepas de S. Heidelberg isoladas na cadeia de produção avícola brasileira e inferir o seu potencial em causar infecções em humanos. Foi avaliado, por PCR, a presença dos genes avrA, invA, lpfA, agfA, sefA, luxS e sodC. Houve 100% de positividade para os genes avrA e invA, 98,4% para agfA, 96,8% para sodC, 87,1% para lpfA, 77,4% para luxS e ausência d o gene sefA. Os genes de virulência encontrados nas amostras alertam para a possível gravidade das infecções causadas por este sorovar. Estes resultados são importantes para maior compreensão dos perfis de patogenicidade de cepas circulantes de S. Heidelberg nos sistemas de produção avícola brasileiros.