Prevalence and Emergence of Extended-Spectrum Cephalosporin-, Carbapenem- and Colistin-Resistant Gram Negative Bacteria of Animal Origin in the Mediterranean Basin

Abstract

In recent years, extended ESBL and carbapenemase producing Gram negative bacteria have become widespread in hospitals, community settings and the environment. This has been triggered by the few therapeutic options left when infections with these multi-drug resistant organisms occur. The emergence of resistance to colistin, the last therapeutic option against carbapenem-resistant bacteria, worsened the situation. Recently, animals were regarded as potent antimicrobial reservoir and a possible source of infection to humans. Enteric Gram negative bacteria in animals can be easily transmitted to humans by direct contact or indirectly through the handling and consumption of undercooked/uncooked animal products. In the Mediterranean basin, little is known about the current overall epidemiology of multi-drug resistant bacteria in livestock, companion, and domestic animals. This review describes the current epidemiology of ESBL, carbapenemase producers and colistin resistant bacteria of animal origin in this region of the world. The CTX-M group 1 seems to prevail in animals in this area, followed by SHV-12 and CTX-M group 9. The dissemination of carbapenemase producers and colistin resistance remains low. Isolated multi-drug resistant bacteria were often co-resistant to non-beta-lactam antibiotics, frequently used in veterinary medicine as treatment, growth promoters, prophylaxis and in human medicine for therapeutic purposes. Antibiotics used in veterinary medicine in this area include mainly tetracycline, aminoglycosides, fluoroquinolones, and polymyxins. Indeed, it appears that the emergence of ESBL and carbapenemase producers in animals is not related to the use of beta-lactam antibiotics but is, rather, due to the co-selective pressure applied by the over usage of non-beta-lactams. The level of antibiotic consumption in animals should be, therefore, re-considered in the Mediterranean area especially in North Africa and western Asia where no accurate data are available about the level of antibiotic consumption in animals.

Colistin-resistant Escherichia coli carrying mcr-1 in food, water, hand rinse, and healthy human gut in Bangladesh

“…Also, eight E. coli strains isolated from street food (n = 3), surface water (n = 2) and healthy human gut (n = 3) had the macrolide resistance gene mphA, which reflects the higher percentage of erythromycin and azithromycin resistance within the isolates (Table 3). Although we have not tested the strains for plasmid carriage, ESBL and mcr-1 genes can co-exist on the same plasmid and therefore could facilitate dissemination of colistin resistance [34]. The E. coli strains carrying mcr-1 were heterogenous genetically, as confirmed by PFGE ( Fig.…”

Prevalence of antimicrobial resistance genes and integrons in commensal Gram-negative bacteria in a college community

“…Previous studies have shown food and the environment to contain ARG found in pathogenic bacteria (12, 23, 24). Environmental reservoirs of ARG-containing pathogens include lakes and rivers (18), wastewater treatment plants (25, 26), houseflies (27), livestock (12, 28, 29), soil and manure (29, 30), retail meat products (12, 31–33), companion animals (5, 6, 8, 28, 34), alfalfa sprouts (35), retail spinach (15), and other vegetables (36). The findings from these studies indicate that human health may be impacted by uptake of pathogens from the environment, many of which harbor ARG on mobile genetic elements.…”

“…Antibiotics are also used in food animal production as growth promoters. Extensive use of antibiotics over the last several decades has led to the rapid emergence and spread of resistant microbes, especially among enteric bacteria (11, 12). Due to the nature and complexity of the microbial communities harbored in our intestinal environment, the human gut has been recognized as a potential reservoir of ARG (3, 13, 14).…”

“…Due to the nature and complexity of the microbial communities harbored in our intestinal environment, the human gut has been recognized as a potential reservoir of ARG (3, 13, 14). However, ARG are also found in food animal intestines as well as in a variety of produce items humans eat (12, 13, 15–17, 21–34). Thus, food may serve as sources of ARGs that enter the human intestine.…”

Extensive antimicrobial resistance and plasmid-carrying resistance genes in mcr-1-positive E. coli sampled in swine, in Guangxi, South China

“…Due to the widespread use of β-Lactam antimicrobial in human and veterinary medicine, the number of extended-spectrum β-lactamase (ESBL)-producing E. coli is rising rapidly worldwide [16,17]. In addition, relevant studies on CREC have been increased in worldwide scale, while CREC is multi-drug resistant microorganism that is difficult to treat and has a high fatality rate on infection [18,19].…”