Detection of Methicillin-Resistant Staphylococci Isolated from Food Producing Animals: A Public Health Implication

Abstract

The emergence of antibiotic-resistant bacteria in food animals is a potential public health concern. Staphylococci are a significant opportunistic pathogen both in humans and dairy cattle. In the present study, the genotypic characterization of methicillin-resistant staphylococcal strains recovered from dairy cattle in a rural community (Okada, Edo State, Nigeria) was investigated. A total of 283 samples from cattle (137 milk samples and 146 nasal swabs) were assessed between February and April 2015. Antimicrobial susceptibility was performed by Kirby-Bauer disc diffusion method. Polymerase chain reaction (PCR) assay was employed for the detection of 16S rRNA, mecA and Panton-Valentine Leucocidinis (PVL) genes. The staphylococcal strains were identified through partial 16S ribosomal ribonucleic acids (rRNA) nucleotide sequencing, and Basic Local Alignment Search Tool (BLAST) analysis of the gene sequence showed that the staphylococcal strains have 96%–100% similarity to Staphylococcus aureus (30), S. epidermidis (17), S. haemolyticus (15), S. saprophyticus (13), S. chromogenes (8), S. simulans (7), S. pseudintermedius (6) and S. xylosus (4). Resistance of 100% was observed in all Staphylococcus spp. against MET, PEN, CLN, CHL and SXT. Multi-drug resistant (MDR) bacteria from nasal cavities and raw milk reveals 13 isolates were MDR against METR, PENR, AMXR, CLNR, CHLR, SXTR CLXR, KANR, ERYR, and VANR. Of all isolates, 100% harboured the mecA gene, while 30% of the isolates possess the PVL gene. All S. aureus harboured the PVL gene while other Staphylococcus spp. were negative for the PVL gene. The presence of methicillin-resistant Staphylococcus spp. isolates in dairy cattle is a potential public health risk and thus findings in this study can be used as a baseline for further surveillance.

Antibiotic resistance profile of Pseudomonas aeruginosa isolated from aquaculture and abattoir environments in urban communities

“…It has been previously reported that antimicrobials are widely used in food animal production settings for treatment/prevention and for growth promotion [9,11]. Studies have also revealed that 50%-90%…”

“…The presence of these organisms coupled with their inherent capacity to resist multiple antibiotics is an enigmatic problem of public health importance [5]. These multidrug resistant pathogenic bacterial isolates which might have emanated from the carcases as a consequence of the continuous use and misuse of antimicrobials as therapeutic/ prophylactic agent as well as growth promoters can be transferred via the food chain to humans [8,9]. Resistance to antimicrobials by pathogenic bacterial isolates can also be a consequence of the ability of the organisms to harbour resistant genes and transmit these genes within bacterial populations via horizontal gene transfer and mobile genetic elements (transposons, plasmids, etc.)…”

Isolation and characterization of antibiotic susceptibility profile of <i>Salmonella</i> species isolated from abattoir environment

“…It has been reported that antibiotics are widely used in food animal production for therapy and prevention of bacterial infection and for growth promotion (Igbinosa et al, 2016). Studies have also shown that 50-90% of drugs administered to farm animals are excreted into the environment either un-metabolized or as metabolic intermediates which even though inactive, may undergo transformation to the active form in the environment (Dahshan et al, 2010;Cabral et al,…”

Prevalence of Methicillin-Resistant Staphylococcus aureus and Other Staphylococcus Species in Raw Meat Samples Intended for Human Consumption in Benin City, Nigeria: Implications for Public Health

“…Staphylococci are pathogens that can cause a range of diseases which are significant to public health [1] and are important food-borne pathogens [1,2]. They are considered the third most significant cause of disease in the world among reported food-borne illnesses [3] coupled with their pathogenicity, which depends on various bacterial surface components [4].…”

“…They are considered the third most significant cause of disease in the world among reported food-borne illnesses [3] coupled with their pathogenicity, which depends on various bacterial surface components [4]. Though the precise role of a particular virulent determinant in relation to infection is difficult to establish, the production of leucocidal toxins, which are expressed by leucocidal genes detected in the genome of staphylococcal isolates recovered from infections resulting in deep and soft tissue infections (furunculosis, severe necrotizing pneumonia and cutaneous abscesses), suggests an important virulence factor in staphylococci: that they harbor the panton-valentine leucocidin (PVL) gene [1,5] which is an attribute for community-acquired methicillin-resistant staphylococci isolates [5]. The secretion of synergohymenotropic toxins resulting from the expression of the PVL gene forms pores in the membrane of host defense cells due to the synergistic action of two secretory proteins, which are designated as LukS-PV and LukF-PV.…”