β-Lactam Resistance Genes: Characterization, Epidemiology, and First Detection of bla_CTX-M-1 and bla_CTX-M-14 in Salmonella spp. Isolated from Poultry in Brazil—Brazil Ministry of Agriculture's Pathogen Reduction Program

Abstract

Salmonella spp. are widespread in nature; however, human infections occur mainly through ingestion of contaminated food, specially poultry and eggs. In Brazil, the Ministry of Agriculture (MAPA) oversees food production in general, with the goal of preventing transmission of pathogens through the food chain. In 2004, MAPA initiated a program to monitor and control levels of Salmonella in poultry during slaughter. This study analyzes isolates from MAPA's program for β-lactam resistance and the resistance genes involved, as well as the geographic distributions of potentially clonal populations of resistant isolates within Brazil. Initially, 1,939 Salmonella spp. isolated between 2004 and 2011 were examined. These isolates were tested for antimicrobial susceptibility, and 100 isolates resistant or intermediate to ampicillin and ceftriaxone were screened initially for the presence of blaSHV, blaTEM, blaOXA, blaPSA, blaCMY-1, and blaCMY-2 genes. There were 55 isolates whose resistance genes were not identified by this panel and these isolates are the subject of this report. These 55 isolates were differentiated into 31 distinct ribogroups, with multiple β-lactam resistance genes, including AmpC blaCMY, blaTEM, blaCTX-M-1, blaCTX-M-2, blaCTX-M-8, and blaCTX-M-14. Isolates carrying variants of blaCTX-M were identified in three geographic regions. Salmonella carrying particular genetic variants of blaCTX-M and belonging to the same ribogroup were identified from multiple poultry slaughtering facilities. In some instances, these presumptive clonal-related isolates were from facilities over 300 miles apart, indicating potential clonal spread between two geographic regions. This is the first report of blaCTX-M-1 and blaCTX-M-14 in Salmonella in Brazil.

Prevalence and Diversity of Salmonella Serotypes in Ecuadorian Broilers at Slaughter Age

“…Although bla TEM and bla SHV are reported as common genes in resistant Salmonella [ 43 , 63 ], these resistance genes were not found in our strains. However, studies in Brazil and USA have identified the bla CTX-M genes as the most prevalent ESBL genes in Salmonella recovered from poultry [ 64 , 65 ] which is in accordance with our results. It should be taken into account that, even though the main families of beta-lactamases were included in this study, resistance to beta-lactams present in the negative strains could be mediated by other ESBL or AmpC genes [ 14 , 66 ].…”

Fecal Colonization of Extended-Spectrum Beta Lactamase-Producing Salmonella spp. in Broilers in Lorestan Province of Iran

“…in Iran are scarce. In line with our findings, bla CTX-M was the predominant ESBL gene recovered from Salmonella in poultry, 24,41,60,61 while some others reported bla TEM 25,62 and bla SHV as the most abundant ESBL genes. 63,64 The bla SHV gene, responsible for resistance to ampicillin, was not detected herein which coincides with the results revealed from Ecuador, northeastern Algeria, China, and northern Egypt.…”

Antimicrobial Resistance in Farm Animals in Brazil: An Update Overview

“…Studies indicate that these genes are mainly carried by E. coli and nontyphoid Salmonella, but also by Escherichia fergusonii, Klebsiella pneumoniae, Citrobacter diversus, and Proteus mirabilis [136][137][138][139][140]. Reports include animals on farms [36,[136][137][138][141][142][143][144][145][146][147], whole carcasses, or meat pieces available in Brazilian retail markets [69,136,138,140,145,148,149], and exported chicken meat [150][151][152]. The same genes were detected in turkeys with clinical signs of colibacillosis [153].…”