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Salmonella cases due to cross-contamination by, or consumption of, raw poultry continue to be a major public health concern. Processors have yet to identify an effective "kill step" in raw poultry production, and food safety interventions may target many compartments of the supply chain, from breeder and grandparent flocks to consumer cooking practices, complicating the prioritization of specific areas to effectively manage risk. Moreover, raw poultry can be contaminated by diverse Salmonella serovars, ranging from multidrug resistant Salmonella Infantis to pansusceptible Salmonella Kentucky sequence type 152, which has substantially reduced likelihood of causing human disease. "Farm-to-table" risk models help assess the public health impact of different Salmonella risk management strategies and thereby inform policy priorities. This article provides an overview of risk management practices that should be considered and evaluated in Salmonella risk assessments, including risk management strategies focusing on (i) preharvest; (ii) slaughter and further processing; (iii) consumer product handling; and (iv) regulatory approaches. Data and model needs to allow assessment of these risk management strategies are also discussed. The information presented here represents a critical step in ensuring that future Salmonella risk assessment and risk management efforts represent a comprehensive systems approach and consider all potential options for Salmonella risk reduction. [ABSTRACT FROM AUTHOR]

Irreversible processes taking place during nonlinear acoustic wave propagation are considered using a representation by loops in a thermodynamic parameter space. For viscous and heat conducting media, the loops are constructed for quasi-harmonic and sawtooth waves and the descriptive equations are formulated. The linear and nonlinear absorptions are compared. For relaxing media, the processes are frequency-dependent. The loops broadens, narrows, and bends. The linear and nonlinear relaxation losses of wave energy are shown. Residual stresses and irreversible strains appear for hysteretic media, and here, a generalization of Rayleigh loops is pictured which takes into account the nonlinearly frequency-dependent hereditary properties. These describe the dynamic behavior, for which new equations are derived. [ABSTRACT FROM AUTHOR]

Salmonella spp. continue to be a leading cause of foodborne morbidity worldwide. To assess the risk of foodborne disease, current national regulatory schemes focus on prevalence estimates of Salmonella and other pathogens. The role of pathogen quantification as a risk management measure and its impact on public health is not well understood. To address this information gap, a quantitative risk assessment model was developed to evaluate the impact of pathogen enumeration strategies on public health after consumption of contaminated ground turkey in the USA. Public health impact was evaluated by using several dose-response models for high- and low-virulent strains to account for potential under- or overestimation of human health impacts. The model predicted 2705-21 099 illnesses that would result in 93-727 reported cases of salmonellosis. Sensitivity analysis predicted cooking an unthawed product at home as the riskiest consumption scenario and microbial concentration the most influential input on the incidence of human illnesses. Model results indicated that removing ground turkey lots exceeding contamination levels of 1 MPN/g and 1 MPN in 25 g would decrease the median number of illnesses by 86-94% and 99%, respectively. For a single production lot, contamination levels higher than 1 MPN/g would be needed to result in a reported case to public health officials. At contamination levels of 10 MPN/g, there would be a 13% chance of detecting an outbreak, and at 100 MPN/g, the likelihood of detecting an outbreak increases to 41%. Based on these model prediction results, risk management strategies should incorporate pathogen enumeration. This would have a direct impact on illness incidence linking public health outcomes with measurable food safety objectives. [ABSTRACT FROM AUTHOR]