Prevalence of ESβL, AmpC and Colistin-Resistant E. coli in Meat: A Comparison between Pork and Wild Boar

Abstract

A global increase in Escherichia coli (E. coli) resistant to cephalosporins (extended-spectrum β-lactamases (ESβLs) and AmpC β-lactamases) has been recorded in the last 20 years. Similarly, several studies have reported the spread of colistin resistance in Enterobacteriaceae isolated from food and the environment. The aim of the present study was to evaluate the prevalence of ESβL, AmpC and colistin-resistant E. coli isolated from pork and wild boar meat products in the Emilia Romagna region (North Italy). The isolates were analysed phenotypically (considering both resistant and intermediate profiles) and genotypically. The prevalence of genotypically confirmed ESβL and AmpC E. coli was higher in pork meat products (ESβL = 11.1% vs. AmpC = 0.3%) compared to wild boar meat (ESβL = 6.5% vs. AmpC = 0%). Intermediate profiles for cefotaxime (CTX) and ceftazidime (CAZ) were genotypically confirmed as ESβL in pork meat isolates but not for wild boar. Four E. coli from wild boar meat were resistant to colistin but did not harbour the mcr-1 gene. E. coli isolated from wild boar meat seem to show aspecific antimicrobial resistance mechanisms for cephalosporins and colistin. The prevalence of resistant isolates found in wild boar is less alarming than in pork from farmed domestic pigs. However, the potential risk to consumers of these meat products will require further investigations.

Antimicrobial Resistance Glides in the Sky—Free-Living Birds as a Reservoir of Resistant Escherichia coli With Zoonotic Potential

“…This result proved that application of phenotypical methods often limited to several antimicrobials, or identification of selected resistance determinants, may lead to underestimation of real AMR status. Similar conclusions were also presented in another study (Rega et al, 2021). That was perfectly illustrated by the E. coli recognized as wild type, isolated from a marsh harrier sampled in nature.…”

Resistance Patterns, mcr-4 and OXA-48 Genes, and Virulence Factors of Escherichia coli from Apennine Chamois Living in Sympatry with Domestic Species, Italy

“…The phenotypic colistin resistance and related mcr genes were reported in wild mammals including fallow deer in Europe [ 17 ], Barbary macaques in Africa [ 13 ] and Père David’s deer in Asia [ 14 ]. In Italy, phenotypic resistance to colistin without evidence of resistance genes was reported in isolates from hunted wild boars in Emilia Romagna [ 18 ], while phenotypic resistance along with mcr-1 and mcr-2 genes were recently detected in hunted wild boars in Tuscany [ 16 ]. In this study, the phenotypic resistance to colistin was reported in isolates from sympatric domestic and wild ungulates, while in the group of non-sympatric animals it was only detected in livestock.…”

“…The blaTEM gene was reported in resistant E. coli from wild boars in Portugal, Poland, and Spain and it was considered by some authors the most frequent gene conferring resistance to β-lactams [ 43 , 45 , 46 ]. Otherwise, in Italy, a low prevalence of bla TEM was reported in resistant isolates from wild boars collected in Emilia Romagna and Lombardy regions [ 18 , 44 ]. Previously, the bla CMY-1 was mainly detected in avian wildlife [ 42 ] and with a low prevalence in resistant E. coli from wild boars in Spain [ 43 ].…”

“…Previously, the bla CMY-1 was mainly detected in avian wildlife [ 42 ] and with a low prevalence in resistant E. coli from wild boars in Spain [ 43 ]. Regarding bla CMY-2, it was earlier reported in hedgehogs, roe deer, and American minks in Spain [ 42 ], while in Italy the bla CMY-2 gene was found in wild boars, badgers, wolves, foxes, and mouflons [ 18 , 28 , 44 ]. The detection of bla SHV, bla TEM, bla CMY-1, and bla CMY-2 in this study is in line with the previous reports and it allows the addition of red deer and Apennine chamois to the list of European wild species showing this genetic resistance profile [ 18 , 28 , 42 , 43 , 44 ].…”

“…Colistin has been used extensively for decades in the treatment and prevention of infectious diseases in veterinary medicine; as a matter of fact, in 2011 polymyxins were the fifth most sold class of antimicrobials for treating food-producing animals in Europe [ 11 ]. Resistance to colistin has increasingly been reported among wild and domestic animals [ 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 ] and a potential horizontal transmission from animals to humans was suggested [ 19 ]. In this context, the use of colistin has been regulated in Europe [ 20 ] and banned as a growth promoter in China [ 21 ].…”