Calves as Main Reservoir of Antibiotic Resistance Genes in Dairy Farms.

A side effect of antibiotic usage is the emergence and dissemination of antibiotic resistance genes (ARGs) within microbial communities. The spread of ARGs among pathogens has emerged as a public health concern. While the distribution of ARGs is documented on a global level, their routes of transmission have not been clarified yet; for example, it is not clear whether and to what extent the emergence of ARGs originates in farms, following the selective pressure exerted by antibiotic usage in animal husbandry, and if they can spread into the environment. Here we address this cutting edge issue by combining data regarding antimicrobial usage and quantitative data from selected ARGs (blaTEM, blaCTXM, ermB, vanA, qnrS, tetA, sul2, and mcr-1) encoding for resistance to penicillins, macrolides-lincosamides-streptogramins, glycopeptides, quinolones, tetracyclines, sulfonamides, and colistin at the farm level. Results suggest that dairy farms could be considered a hotspot of ARGs, comprising those classified as the highest risk for human health and that a correlation existed between the usage of penicillins and blaTEM abundances, meaning that, although the antibiotic administration is not exclusive, it remains a certain cause of the ARGs' selection and spread in farms. Furthermore, this study identified the role of calves as the main source of ARGs spread in dairy farms, claiming the need for targeted actions in this productive category to decrease the load of ARGs along the production chain.

Insight into an outbreak of Salmonella Choleraesuis var. Kunzendorf in wild boars.

An unusual mortality of wild boars occurred in Italy from 2012 to 2015 due to Salmonella Choleraesuis infection. In order to confirm the occurrence of an outbreak of S. Choleraesuis in wild boars and to epidemically characterise the unique S. Choleraesuis biovar, a collection of isolates belonging to wild boars was investigated from the phenotypic, molecular and genomic points of view (PFGE and WGS). Moreover, the possibility of transmission to domestic pigs and humans, temporally and geographically close to the wild boar epidemic, was tested by also including in the panel isolates from infected domestic pigs and from one human case of infection. Wild boar isolates displayed a high genetic correlation, thus suggesting they are part of the same outbreak, with a common invasiveness potential. Conversely, no correlation between pig isolates and those from the other sources (wild boars and human) was found. However, the phylogenetic and PFGE analyses suggest a high degree of similarity between the human and the investigated wild boar outbreak isolates, implying the potential for the spread of Salmonella Choleraesuis among these species.

A Comparative Genomic Analysis Provides Novel Insights Into the Ecological Success of the Monophasic Salmonella Serovar 4,[5],12:i:.

Over the past decades, Salmonella 4,[5],12:i:- has rapidly emerged and it is isolated with high frequency in the swine food chain. Although many studies have documented the epidemiological success of this serovar, few investigations have tried to explain this phenomenon from a genetic perspective. Here a comparative whole-genome analysis of 50 epidemiologically unrelated S. 4,[5],12:i:-, isolated in Italy from 2010 to 2016 was performed, characterizing them in terms of genetic elements potentially conferring resistance, tolerance and persistence characteristics. Phylogenetic analyses indicated interesting distinctions among the investigated isolates. The most striking genetic trait characterizing the analyzed isolates is the widespread presence of heavy metals tolerance gene cassettes: most of the strains possess genes expected to confer resistance to copper and silver, whereas about half of the isolates also contain the mercury tolerance gene merA. A functional assay showed that these genes might be useful for preventing the toxic effects of metals, thus supporting the hypothesis that they can contribute to the success of S. 4,[5],12:i:- in farming environments. In addition, the analysis of the distribution of type II toxin-antitoxin families indicated that these elements are abundant in this serovar, suggesting that this is another factor that might favor its successful spread.

Risk communication by health professionals: an analysis of press releases drafted by Italian veterinarians.

The aim of this study is to analyse and evaluate the knowledge concerning risk communication acquired by veterinarians during a national training course. The study analyses 694 press releases written during the training course. Textual variables and indexes were considered to identify the linguistic structures used by veterinarians. At first, the analysis of press releases focused on the descriptive demographic variables, then stylistic and editorial variables were considered, and finally a lexicographic analysis was performed on the textual variables. The texts were found to have a moderate level of readability due to the use of scientific and technical terms. This study shows the need to improve training activities to develop effective risk communication, especially in terms of the language used, in order to facilitate interactions among veterinarians, mass media, and citizens.

Food safety and hygiene lessons in the primary school: implications for risk-reduction behaviors.

OBJECTIVE: This study describes an effective educational program to improve children's knowledge about characteristics of microorganisms and food contamination, and their personal hygiene behaviors. MATERIALS AND METHODS: Between November 2011 and March 2012, a health campaign, targeted at fifth-grade students of 12 public primary compulsory schools, was conceived. Participants were divided into two classes, a theoretical class and a practical class based on two different teaching approaches. To address children's knowledge and behaviors on the program topics and to monitor the effectiveness of the health campaign on changing pre-existent concepts and habits, pre- and post-intervention questionnaires were administered both to students and parents. Poisson and binomial mixed models were performed. RESULTS: Two hundred forty-nine children were enrolled. Results show an overall improvement in children's knowledge both for the practical and theoretical classes (incident risk ratios [IRRs]: 1.2, 95% confidence interval (CI) 1.1-1.2, p<0.001 and 1.1, 95% CI 1.0-1.1, p<0.001, post- versus pre-intervention). The same effect was observed for children's behavior, comparing post- versus pre-intervention for both groups (IRRs were 3.4, 95% CI 2.2-5.2, p<0.001 and 3.2 95% CI 1.9-5.5, p<0.001). CONCLUSION AND APPLICATIONS: The methodology described in this article might be usefully adopted to conduct food safety classes, contributing to the amelioration of children's awareness on food related risks and leading to significant benefit for primary prevention.