Characterization of mannitol-fermenting methicillin-resistant staphylococci isolated from pigs in Nigeria

Abstract

This study was conducted to determine the species distribution, antimicrobial resistance pheno- and genotypes and virulence traits of mannitol-positive methicillin-resistant staphylococci (MRS) isolated from pigs in Nsukka agricultural zone, Nigeria. Twenty mannitol-positive methicillin-resistant coagulase-negative staphylococcal (MRCoNS) strains harboring the mecA gene were detected among the 64 Staphylococcus isolates from 291 pigs. A total of 4 species were identified among the MRCoNS isolates, namely, Staphylococcus sciuri (10 strains), Staphylococcus lentus (6 strains), Staphylococcus cohnii (3 strains) and Staphylococcus haemolyticus (one strain). All MRCoNS isolates were multidrug-resistant. In addition to β-lactams, the strains were resistant to fusidic acid (85%), tetracycline (75%), streptomycin (65%), ciprofloxacin (65%), and trimethoprim/sulphamethoxazole (60%). In addition to the mecA and blaZ genes, other antimicrobial resistance genes detected were tet(K), tet(M), tet(L), erm(B), erm(C), aacA-aphD, aphA3, str, dfrK, dfrG, cat pC221, and cat pC223. Thirteen isolates were found to be ciprofloxacin-resistant, and all harbored a Ser84Leu mutation within the QRDR of the GyrA protein, with 3 isolates showing 2 extra substitutions, Ser98Ile and Arg100Lys (one strain) and Glu88Asp and Asp96Thr (2 strains). A phylogenetic tree of the QRDR nucleotide sequences in the gyrA gene revealed a high nucleotide diversity, with several major clusters not associated with the bacterial species. Our study highlights the possibility of transfer of mecA and other antimicrobial resistance genes from MRCoNS to pathogenic bacteria, which is a serious public health and veterinary concern.

Frequency and Characterization of Antimicrobial Resistance and Virulence Genes of Coagulase-Negative Staphylococci from Wild Birds in Spain. Detection of tst-Carrying S. sciuri Isolates

“…It is necessary to note the high tetracycline resistance rate (60%) observed among the S. lentus isolates with respect to the overall tetracycline rate of CoNS (17%), which was mostly mediated by the tet (K) gene. Similar resistance rates in S. lentus were detected in isolates recovered from livestock [ 29 , 35 ], which could be attributable to the extended use of this antimicrobial in veterinary medicine. The location of dfr (K) next to the tet (L) gene in one S. lentus isolate suggests their location in a pKKS2187-like plasmid previously reported among MRSA-CC398 and MRCoNS of pig origin [ 29 , 36 ].…”

“…Similar resistance rates in S. lentus were detected in isolates recovered from livestock [ 29 , 35 ], which could be attributable to the extended use of this antimicrobial in veterinary medicine. The location of dfr (K) next to the tet (L) gene in one S. lentus isolate suggests their location in a pKKS2187-like plasmid previously reported among MRSA-CC398 and MRCoNS of pig origin [ 29 , 36 ]. This supports the hypothesis that red kites could acquire CoNS from livestock carrion at the vulture restaurant via direct contact or the food chain.…”

“…S. lentus was the second species most frequently recovered in this study and was especially prevalent among red kites. This staphylococcal species is commonly detected among farm animals and people with professional exposure to livestock [ 16 , 28 , 29 ]. More frequent colonization of obligate and frequent scavengers by S. sciuri and S. lentus suggests that despite being respiratory tract colonizers, carrion feeding may increase the exposure.…”

Antimicrobial Resistance in Food Animals and the Environment in Nigeria: A Review

“…This category included 42 studies, with the inclusive eligibility criteria in which diverse phenotypic or genotypic methods were utilized ([14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55], Tables S1–S3). These studies sought to detect the presence and extent of AMR in collected samples with a selected panel of antibiotics.…”

“…The 80 studies excluded did not directly relate to the objectives or yielded information that could be subjected to organized peer review and data analysis. The 59 included studies were sorted into three categories of 42 antimicrobial resistance studies [14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55], 16 antimicrobial residue studies [56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71], and 1 antiseptic or disinfectants study [72]. The PRISMA-style flowchart was modified and used for this analytical review (Figure S1) [73].…”