Antimicrobial Resistance and Genetic Lineages of <i>Staphylococcus aureus</i> from Wild Rodents: First Report of <i>mec</i>C-Positive Methicillin-Resistant <i>S. aureus</i> (MRSA) in Portugal
Vanessa Silva,
Sofia I. Gabriel,
Sofia B. Borrego,
Maria Teresa Tejedor-Junco,
Vera Manageiro,
Eugénia Ferreira,
Lígia Reis,
Manuela Caniça,
José L. Capelo,
Gilberto Igrejas,
Patrícia Poeta
Affiliations
Vanessa Silva
Microbiology and Antibiotic Resistance Team (MicroART), Department of Veterinary Sciences, University of Trás-os-Montes and Alto Douro (UTAD), 5000-801 Vila Real, Portugal
Sofia I. Gabriel
CESAM—Centro de Estudos do Ambiente e do Mar, Departamento de Biologia da Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal
Sofia B. Borrego
Direção Regional da Agricultura, Secretaria Regional da Agricultura e Desenvolvimento Rural, Quinta de São Gonçalo, 9500-343 Ponta Delgada, Portugal
Maria Teresa Tejedor-Junco
Research Institute of Biomedical and Health Sciences, University of Las Palmas de Gran Canaria, 35001 Canary Islands, Spain
Vera Manageiro
National Reference Laboratory of Antibiotic Resistances and Healthcare Associated Infections (NRL-AMR/HAI), Department of Infectious Diseases, National Institute of Health Dr Ricardo Jorge, 1649-016 Lisbon, Portugal
Eugénia Ferreira
National Reference Laboratory of Antibiotic Resistances and Healthcare Associated Infections (NRL-AMR/HAI), Department of Infectious Diseases, National Institute of Health Dr Ricardo Jorge, 1649-016 Lisbon, Portugal
Lígia Reis
National Reference Laboratory of Antibiotic Resistances and Healthcare Associated Infections (NRL-AMR/HAI), Department of Infectious Diseases, National Institute of Health Dr Ricardo Jorge, 1649-016 Lisbon, Portugal
Manuela Caniça
National Reference Laboratory of Antibiotic Resistances and Healthcare Associated Infections (NRL-AMR/HAI), Department of Infectious Diseases, National Institute of Health Dr Ricardo Jorge, 1649-016 Lisbon, Portugal
José L. Capelo
BIOSCOPE Group, LAQV@REQUIMTE, Chemistry Department, Faculty of Science and Technology, NOVA University of Lisbon, 2825-466 Almada, Portugal
Gilberto Igrejas
Department of Genetics and Biotechnology, Functional Genomics and Proteomics’ Unit, University of Trás-os-Montes and Alto Douro, 5000-801 Vila Real, Portugal
Patrícia Poeta
Microbiology and Antibiotic Resistance Team (MicroART), Department of Veterinary Sciences, University of Trás-os-Montes and Alto Douro (UTAD), 5000-801 Vila Real, Portugal
The frequent carriage of Staphylococcus aureus, including methicillin-resistant S. aureus (MRSA), by wild animals along with its zoonotic potential poses a public health problem. Furthermore, the repeated detection of the mecA gene homologue, mecC, in wildlife raises the question whether these animals may be a reservoir for mecC-MRSA. Thus, we aimed to isolate S. aureus and MRSA from wild rodents living in port areas and to characterize their antimicrobial resistance and genetic lineages. Mouth and rectal swab samples were recovered from 204 wild rodents. The samples were incubated in BHI broth with 6.5% of NaCl and after 24 h at 37 °C the inoculum was seeded onto Baird-Parker agar, Mannitol Salt agar and ORSAB (supplemented with 2 mg/L of oxacillin) plates. Species identification was confirmed by MALDI-TOF MS. The antimicrobial susceptibility testing was performed by the Kirby–Bauer disc diffusion method against 14 antibiotics. The presence of virulence and resistance genes was performed by PCR. The immune evasion cluster (IEC) system was investigated in all S. aureus. All isolates were characterized by MLST, spa- and agr typing. From 204 samples, 38 S. aureus were isolated of which six MRSA were detected. Among the six MRSA isolates, three harbored the mecC gene and the other three, the mecA gene. All mecC-MRSA isolates were ascribed to sequence type (ST) 1945 (which belongs to CC130) and spa-type t1535 whereas the mecA isolates belonged to ST22 and ST36 and spa-types t747 and t018. Twenty-five S. aureus were susceptible to all antibiotics tested. S. aureus isolates were ascribed to 11 MLST and 12 spa-types. S. aureus presents a great diversity of genetic lineages in wild rodents. This is the first report of mecC-MRSA in Portugal.
