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Pulmonary aspiration of gastric refluxate (PAGR) has been demonstrated in association with pulmonary inflammation in school aged children with Cystic Fibrosis (CF). We sought to determine if similar findings were present in preschool children. Pepsin was measured in Broncho-alveolar lavage (BAL) fluid collected from clinically stable preschool children with CF and controls. Elevated pepsin levels were found in a subgroup of children with CF, but this was not found to be associated with pulmonary infection, pulmonary inflammation or respiratory or gastrointestinal symptoms.

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Cryptosporidiosis caused by Cryptosporidium parvum infection is a major cause of enteric illness in man and there is a significant reservoir in animals, particularly young ruminant species. To preliminary assess the magnitude of the risk posed by contact with faeces produced by infected livestock, two microbiological risk assessments have been developed: one for the risk of human infection with C. parvum while camping on contaminated land recently grazed by infected suckler cattle and a comparable risk assessment for camping on land recently spread with contaminated cattle slurry. Using a worst-case scenario approach, the upper level of risk was estimated to be one infection in every 6211 person-visits for a camping event on land recently grazed by infected cattle. Translated into camping events of 100 persons, this risk estimate would most likely lead to zero (98% likelihood) or one infection (1% likelihood). The results for cattle slurry model are similar despite different pathways. Sensitivity analysis was conducted for the grazing cattle model only. This suggested that the time between grazing and camping was the most important control strategy, but increasing hand-washing frequency and the removal of cattle faeces before camping would also be beneficial. If the upper level of risk were to be judged unacceptable then further data would be required to more accurately estimate the risk of infection through these scenarios. Further research would also be required to assess the fraction of cases attributable to camping and/or environmental contact with Cryptosporidium oocysts.

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AIMS: To investigate the transfer of antibiotic resistance from a donor Salmonella Typhimurium DT104 strain to a recipient Escherichia coli K12 strain. METHODS AND RESULTS: Mating experiments were conducted in broth, milk and ground meat (beef) at incubation temperatures of 4, 15, 25 and 37 degrees C for 18 and 36 h. Ampicillin-resistance transfer was observed at similar frequencies in all transfer media at 25 and 37 degrees C (10(-4) to 10(-5) log(10 )CFU ml g(-1), transconjugants per recipient) for 18 h. At 15 degrees C, transfer was observed in ground meat in the recipient strain (10(-6), log10 CFU g(-1), transconjugants per recipient), but not in broth or milk. At 4 degrees C, transfer did not occur in any of the examined mediums. Further analysis of the E. coli K12 nal transconjugant strain revealed the presence of a newly acquired plasmid (21 kbp) bearing the beta-lactamase gene bla(TEM). Transconjugants isolated on the basis of resistance to ampicillin did not acquire any other resistant markers. CONCLUSION: This study demonstrates the transfer of antibiotic resistance in food matrices at mid-range temperatures. SIGNIFICANCE AND IMPACT OF THE STUDY: It highlights the involvement of food matrices in the dissemination of antibiotic-resistant genes and the evolution of antibiotic-resistant bacteria.

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A second-order quantitative Monte Carlo simulation model was developed for Escherichia coli O157:H7 contamination of beef trimmings in Irish abattoirs. The assessment considers initial contamination levels, cross-contamination and decontamination events during the cattle slaughter process. The mean simulated prevalence of E. coli O157:H7 on trimmings was 2.36% and the mean simulated counts of E. coli O157:H7 on contaminated trimmings was -2.69log(10)CFU/g. A parallel validation survey provided some confidence in the model predictions. An uncertainty analysis indicated that microbial test sensitivity is a significant factor contributing to model uncertainty and requires further investigation while also indicating that risk reduction measures should be directed towards reducing the hide to carcass transfer (correlation coefficient 0.25) during dehiding and reducing the initial prevalence and counts on bovine hides (correlation coefficients 0.19 and 0.16, respectively). A characterisation of uncertainty and variability indicating that further research is required to reduce parameter uncertainty and to achieve better understanding of microbial transfer in meat plants. The model developed in this study highlights the need for further development of quantitative risk assessments in the food industry.