Methicillin resistant Staphylococcus aureus (MRSA) carriage in different free-living wild animal species in Spain

Methicillin-resistant Staphylococcus aureus (MRSA) is a life-threatening pathogen in humans and its presence in animals is a public health concern. The aim of this study was to measure the prevalence of MRSA in free-living wild animals. Samples from red deer (n= 273), Iberian ibex (n= 212), Eurasian Griffon vulture (n= 40) and wild boar (n= 817) taken from different areas in Spain between June 2008 and November 2011 were analyzed. Characterization of the isolates was performed by spa typing, multi-locus sequence typing (MLST) and antimicrobial susceptibility testing. A low prevalence of MRSA was found with 13 isolates obtained from 12 animals (0.89%; 95% CI: 0.46-1.56). All MRSA sequence types belonged to ST398 (t011 and t1451) and ST1 (t127). Genotypes and antimicrobial susceptibility patterns (tetracycline resistance in ST398 and clindamycin-erythromycin-tetracycline resistance in ST1) suggest that the MRSA found probably originated in livestock (ST398) or humans (ST1). This is the first report of MRSA carriers in free-living wild animals in Europe. Although our data showed that MRSA prevalence is currently low, free-living wild animals might act as reservoir and represent a potential risk for human health.This work was partially supported by the Ministry of Science and Innovation within the Program of Interaction between wild animals and livestock (FAU200600011; FAU2008-00021) and by the Autonomous Community of Madrid, Spain (S0505/AGR-0265; S2009/AGR-1489). Eurasian Griffon vultures were captured within the Territorial Cooperation Programme Spain-France-Andorra (NECROPIR-EFA 130/09). E. Serrano was supported by the Beatriu de Pinós programme (BP-DGR 2011) of the Catalan Science and Technology System and N. Navarro-Gonzalez by the FPU programme of the Ministry of Education (Spain).Peer Reviewe