Salmonella Contamination in Ready-to-Eat Tilapia Sashimi Processing Plants

Inactivation of Salmonella Typhimurium, Escherichia coli, and Staphylococcus aureus in Tilapia Fillets (Oreochromis niloticus) with Lactic and Peracetic Acid through Fogging and Immersion

This study investigated the antimicrobial effects of lactic acid (LA) (3%) and peracetic acid (PA) (300 ppm) on tilapia fillets (Oreochromis niloticus) by fogging (15 min) or by immersion (2 s) in a pool of Escherichia coli (NEWP 0022, ATCC 25922, and a field-isolated strain), Staphylococcus aureus (ATCC 25923 and a field-isolated strain), and Salmonella Typhimurium (ATCC 13311 and ATCC 14028), as well as the effects on the physicochemical characteristics of the fillets. Fogging was effective and the best application method to control S. Typhimurium regardless of the acid used, promoting reductions of 1.66 and 1.23 log CFU/g with PA and LA, respectively. Regarding E. coli, there were significant reductions higher than 1 log CFU/g, regardless of the treatment or acid used. For S. aureus, only immersion in PA showed no significant difference (p < 0.05). For other treatments, significant reductions of 0.98, 1.51, and 1.17 log CFU/g were observed for nebulized PA, immersion, and LA fogging, respectively. Concerning the pH of the samples, neither of the acids used differed from the control. However, treatments with LA, and fogging with PA, reduced the pH compared to immersion in PA. As for color parameters, L* and a* values showed changes regardless of the acid or method used, resulting in an improved perception of fillet quality. These results indicate that fogging and immersion are alternatives for reducing S. Typhimurium, E. coli, and S. aureus in tilapia fillets.

Persistence of microbiological hazards in food and feed production and processing environments

Listeria monocytogenes (in the meat, fish and seafood, dairy and fruit and vegetable sectors), Salmonella enterica (in the feed, meat, egg and low moisture food sectors) and Cronobacter sakazakii (in the low moisture food sector) were identified as the bacterial food safety hazards most relevant to public health that are associated with persistence in the food and feed processing environment (FFPE). There is a wide range of subtypes of these hazards involved in persistence in the FFPE. While some specific subtypes are more commonly reported as persistent, it is currently not possible to identify universal markers (i.e. genetic determinants) for this trait. Common risk factors for persistence in the FFPE are inadequate zoning and hygiene barriers; lack of hygienic design of equipment and machines; and inadequate cleaning and disinfection. A well-designed environmental sampling and testing programme is the most effective strategy to identify contamination sources and detect potentially persistent hazards. The establishment of hygienic barriers and measures within the food safety management system, during implementation of hazard analysis and critical control points, is key to prevent and/or control bacterial persistence in the FFPE. Once persistence is suspected in a plant, a 'seek-and-destroy' approach is frequently recommended, including intensified monitoring, the introduction of control measures and the continuation of the intensified monitoring. Successful actions triggered by persistence of L. monocytogenes are described, as well as interventions with direct bactericidal activity. These interventions could be efficient if properly validated, correctly applied and verified under industrial conditions. Perspectives are provided for performing a risk assessment for relevant combinations of hazard and food sector to assess the relative public health risk that can be associated with persistence, based on bottom-up and top-down approaches. Knowledge gaps related to bacterial food safety hazards associated with persistence in the FFPE and priorities for future research are provided.

Clinical Characteristics and Drug Resistance Analysis of 90 Cases of Children with Salmonella Enteritis

Objective. To summarize the clinical characteristics and drug sensitivity analysis of children with Salmonella enteritis in our hospital, explore the characteristics and drug resistance of Salmonella infection, and guide the rational clinical use of drugs. Methods. The clinical data of 90 pediatric Salmonella enteritis patients treated in our hospital from January 2015 to January 2020 were selected as the observation group of this retrospective study, and 90 patients with non-Salmonella enteritis were selected at the same time as a control group. Discuss the clinical characteristics of Salmonella, drug sensitivity analysis, infection characteristics, and drug resistance and guide the rational clinical use of drugs. Results. The susceptibility rates of 15 antibiotics from high to low were imipenem and meropenem, piperacillin, cefoperazone, compound trimethoprim, chloramphenicol, and ceftazidime. Salmonella strains were both resistant to imipenem and meropenem. Salmonella is sensitive and has a low rate of resistance to quinolones (ciprofloxacin) and a high rate of resistance to cephalosporins (ceftriaxone, cefotaxime, ceftazime, and cefpiramide), both reached more than 28%. Salmonella has the highest resistance to penicillin and erythromycin, both at 85.00% and above. Among 90 children with Salmonella enteritidis food poisoning, 32 were hospitalized, 21 cases were hospitalized less than 7 days, and 11 cases were 7-14 days. The longest hospital stay was 12 days, the shortest was 1 day, and the average was 6.1 days. Seven people stayed for observation and 51 people were discharged after treatment. All the children recovered without death. Conclusion. In clinical practice, antibiotics should be used rationally based on drug susceptibility results. In the case of poor efficacy of cephalosporins, amoxicillin and potassium clavulanate, piperacillin, tazobactam, or imipenem, cephalosporin antibiotics can be considered the first choice for clinical empiric medication.