Chapter 12 : The Evolution of Antibiotic-Resistant Microbes in Foods and Host Ecosystems

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In the years between the introduction of antibiotic therapy and the mid-1970s, antibiotic-resistant bacteria were generally restricted to the hospital setting and epidemic diseases which were not major issues in much of the industrialized world. In this chapter, the development of tetracycline-resistant (Tc) fish pathogens and bacteria associated with aquaculture environments is discussed. Antibiotic residues may be found in a variety of foods produced around the world. Currently, unlabeled but high levels of cephalosporins (ceftiofur) are allowed in some foods. Rules exist which aim to minimize the level of antibiotic residues found in food products; however, not all foods are tested, nor is it clear that the standards required by farms in North America and Europe are followed when the food is produced for overseas consumption. The majority of the novel genes were mobile elements carrying antibiotic resistance and virulence genes. are normal inhabitants of the intestinal flora of most mammals, birds, and humans, as well as from soil, surface waters, plants, vegetables, raw foods such as milk and meat, and fermented meats such as Italian salami or raw sausage. Studies have shown that fish foods, even unlabeled ones, may contain antibiotic-resistant bacteria and/or antibiotic residues. This chapter also illustrates a few examples in which specific antibiotic resistance genes, regions of DNA, and/or plasmids have been found in bacteria from very different ecosystems, from different parts of the world, and in bacteria that are host species-specific.

Citation: Roberts M. 2009. The Evolution of Antibiotic-Resistant Microbes in Foods and Host Ecosystems, p 213-229. In Jaykus L, Wang H, Schlesinger L (ed), Food-Borne Microbes. ASM Press, Washington, DC. doi: 10.1128/9781555815479.ch12
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