Where is the prevalence of genes for extended spectrum cephalosporins high?

The prevalence of genes for extended spectrum cephalosporins is particularly high in US livestock due to the significant use of antibiotics in agricultural settings, especially in the production of food animals. Livestock farming often employs these drugs to prevent and treat infections as well as to promote growth, leading to an increased selection pressure for antibiotic-resistant bacteria. The overuse and mismanagement of antibiotics in these environments contribute to the spread of resistance genes among bacterial populations. This situation is further exacerbated by the close proximity of livestock to humans and the environment, facilitating the potential transfer of these genes to human pathogens and other ecological habitats.

While other areas, such as terrestrial mammals, aquatic species, and wild animals, can also harbor resistance genes, the concentration and prevalence are notably higher in livestock due to the scale of antibiotic use and farming practices in the United States. This highlights the importance of implementing effective antimicrobial stewardship practices in agriculture to control the spread of resistance.