Prevalence of Methicillin-Resistant S. aureus, Extended-Spectrum β-Lactamase-Producing E. coli, and Vancomycin-Resistant E. faecium in the Production Environment and Among Workers in Low-Capacity Slaughterhouses in Poland

<b>Background:</b> Small-scale food animal production is common worldwide but often underestimated as a source of antimicrobial resistance. This study aimed to determine the prevalence of MRSA and VRE-<i>E. faecium</i>, and ESBL-<i>E. coli</i> bacteria among workers and within the production environment of low-capacity slaughterhouses, as well as to analyze the antimicrobial resistance patterns of these bacteria and their ability to form biofilms. <b>Methods:</b> The measurements were carried out in three low-capacity slaughterhouses in Poland. Bioaerosol samples, swabs from the production environment fomite and carcasses, meat samples, and swabs from workers' hands and nostrils were taken. The strains' susceptibility to antibiotics was assessed using the disk diffusion method, and their biofilm-forming potential was assessed using the microplate method. Isolates were also tested for the presence of genes related to biofilm formation and resistance to antiseptics. <b>Results:</b> In this study, 13.8%, 20.5%, and 14.9% of the samples (<i>n</i> = 268) were positive for MRSA, ESBL-<i>E. coli</i>, and VRE-<i>E. faecium</i>, respectively, with the highest detection rates on pork carcasses and surfaces. MRSA and ESBL-<i>E. coli</i> bacteria were also detected in swabs from workers' hands and nasal swabs, and in bioaerosol samples. Most isolates revealed multidrug resistance, including 89% of MRSA, 76% of ESBL-<i>E. coli</i>, and 83% of VRE-<i>E. faecium</i>. The majority of them were also capable of biofilm formation-81%, 65%, and 75%, respectively-emphasizing their survival capabilities in slaughterhouse environments. <b>Conclusions:</b> The slaughterhouse workers are regularly exposed to antibiotic-resistant bacteria such as MRSA, ESBL-<i>E. coli</i>, and VRE-<i>E. faecium</i>. To reduce these risks, it is essential for small slaughterhouses to strictly follow hygiene protocols, enhance the separation between clean and contaminated areas, improve ventilation, and ensure the use of protective measures.