Illustrative examples of probable transfer of resistance determinants from food animals to humans: Streptothricins, glycopeptides, and colistin

Abstract

Use, overuse, and misuse of antimicrobials contributes to selection and dissemination of bacterial resistance determinants that may be transferred to humans and constitute a global public health concern. Because of the continued emergence and expansion of antimicrobial resistance, combined with the lack of novel antimicrobial agents, efforts are underway to preserve the efficacy of current available life-saving antimicrobials in humans. As a result, uses of medically important antimicrobials in food animal production have generated debate and led to calls to reduce both antimicrobial use and the need for use. This manuscript, commissioned by the World Health Organization (WHO) to help inform the development of the WHO guidelines on the use of medically important antimicrobials in food animals, includes three illustrations of antimicrobial use in food animal production that has contributed to the selection—and subsequent transfer—of resistance determinants from food animals to humans. Herein, antimicrobial use and the epidemiology of bacterial resistance are described for streptothricins, glycopeptides, and colistin. Taken together, these historical and current narratives reinforce the need for actions that will preserve the efficacy of antimicrobials.

Plasmid-Mediated mcr-1 Colistin Resistance in Escherichia coli from a Black Kite in Russia

“…In veterinary medicine, apart from therapeutic purposes, colistin is used also as an in-feed growth promoter in livestock in some Asian countries, including India, Japan, and Vietnam (2). As a result of growing concern about emerging mobile colistin resistance, the use of colistin in food-producing animals is globally limited or banned (3). Plasmid-mediated colistin resistance gene mcr-1 has been described in more than 40 countries, with the majority of reports coming from inpatients and domestic animals.…”

A review on the current situation and challenges of colistin resistance in poultry production

“…However, during the last two decades, the situation has dramatically changed. The emergence of multidrug-resistant (MDR), extremely drugresistant (XDR) or even pan-drug-resistant (PDR) bacteria (Jeannot et al, 2017) is responsible for the deaths of 700,000 people annually; this is estimated to surpass cancer victims by 2050 (O'Neill, 2016;Webb et al, 2017). In a world close to the "post-antibiotic era", colistin has resurged as a last-resort drug in the arsenal against resistant bacteria such as carbapenemase-producers, A. baumannii and P. aeruginosa.…”

“…On the other side of the Atlantic, the United States Food and Drug Administration (FDA) and the Public Health Agency (PHA) of Canada have never licenced a colistin-containing product for oral use in livestock. There is, however, a documented off-label use allowed by regulation loopholes (Webb et al, 2017). At the global level, China is by far the leading colistin producer (17.5 million tonnes) and, at the same time, the largest consumer absorbing over 90% of its production (Liu et al, 2016).…”

“…Colistin products are chiefly administered in group treatments through the oral route via feed or, more often, via drinking water. The 495 tonnes of polymyxins consumed in 2013 in Europe were predominantly administered orally to swine and poultry (Webb et al, 2017). In France, for example, exposure of pigs to colistin accounted for one-third of the total exposure to antimicrobials and the corresponding proportion was even higher for poultry (Kempf et al, 2013).…”

“…Epidemiological data and the widespread use of colistin in animal husbandry have led to the belief that transmissible colistin resistance has emerged and is being transferred from animals to humans . Among food-producing animals, a multitude of investigations has demonstrated a notable prevalence of colistin resistance in poultry worldwide, especially in Asia (Kempf et al, 2016;Jeannot et al, 2017;Webb et al, 2017).…”