Transmission of β-lactamases in the pork food chain: A public health concern

Martina Rega; Laura Andriani; Antonio Poeta; Chiara Casadio; Giuseppe Diegoli; Silvia Bonardi; Mauro Conter; Cristina Bacci

doi:10.1016/j.onehlt.2023.100632

Transmission of β-lactamases in the pork food chain: A public health concern

One Health. 2023 Sep 24:17:100632. doi: 10.1016/j.onehlt.2023.100632. eCollection 2023 Dec.

Authors

Martina Rega¹, Laura Andriani¹, Antonio Poeta², Chiara Casadio³, Giuseppe Diegoli⁴, Silvia Bonardi¹, Mauro Conter¹, Cristina Bacci¹

Affiliations

¹ Food Hygiene and Inspection Unit, Veterinary Science Department, University of Parma, Strada del Taglio, 10, 43126 Parma, Italy.
² Azienda Unità Sanitaria Locale (AUSL) sede Reggio Emilia, via Amendola 2, 42122 Reggio Emilia, Italy.
³ Azienda Unità Sanitaria Locale (AUSL) sede Modena, Via S. Giovanni del cantone, 23 41121 Modena, Italy.
⁴ Emilia-Romagna Region, Collective Prevention and Public Health Service, viale Aldo Moro 21, 40127 Bologna, Italy.

Abstract

Antimicrobial resistance (AMR) is a risk for public health that requires management in a One Health perspective, including humans, animals, and the environment. The food production chain has been identified as a possible route of transmission of AMR bacteria to humans. The most critical issue regards resistance to the Critically Important Antimicrobials (CIAs), such as β-lactams antibiotics. Here, pigs were analysed along the entire food producing chain, including feces, carcasses and pork products (fresh meat, fermented and seasoned products) ensuring treaciability of all samples. Escherichia coli were isolated and their ability to produce ESBL and AmpC β-lactamases was evaluated both phenotypically and genotypically. Strains with the same AMR profile from feces, carcasses, and meat products were selected for phylogenetic and comparative genomic analyses to evaluate the possible "farm-to-fork" transmission of β-lactams resistant bacteria. Results showed that the percentage of ESBL strains in fecal E. coli was approximately 7% and increased slightly in the pork food chain: the 10% of ESBL E. coli isolated from carcasses and the 12.5% of isolates from fresh meat products. AmpC E. coli were found only in feces, carcasses, and fresh meat with a low prevalence. Results showed that of the 243 pigs followed along the entire food chain genetic similarities in E. coli isolated from farm-to-fork were found in only one pig (feces, carcasses and fresh meat). Frequent similarities were shown in resistant E. coli isolates from carcasses and fresh meat or fermented product (three pork food chain). Moreover, in one case, bacteria isolated from fresh meat and fermented product were genotypically similar. Concluding, direct transmission of β-lactams resistance from farm-to-fork is possible but not frequent. Further studies are needed to improve risk communication to consumers and access to clear and reliable information and health concerns on food.

Keywords: AmpC; ESBL; Meat; Pork food chain; Public health; β-lactamases.