The prevalence of antimicrobial-resistant bacteria has dramatically increased in hospitals worldwide during the last decades. Within hospitals, Staphylococcus aureus is a major human pathogen, with methicillin-resistant S. aureus (MRSA) causing serious hospital complications (3).
Genotype analyses of MRSA hospital isolates have confirmed the existence of epidemic clones with great capacity to spread and to fit in hospital environments. One of these clones, UK EMRSA-16, is one of the two main causes of MRSA infections in the United Kingdom, and together UK EMRSA-15 and EMRSA-16 cause 95% of MRSA bacteremias. UK EMRSA-16 has been studied extensively and has been confirmed to be the causal agent of most hospital staphylococcal outbreaks in the United Kingdom. Although it has been considered to be largely restricted to the United Kingdom, two recent multicenter studies have shown that this clone is also present in Belgium, Finland, Sweden, and Denmark (2, 4).
In this letter, we briefly and urgently communicate that we have detected the UK EMRSA-16 multiresistant clone as an epidemic clone in a university hospital in Tenerife, Spain. To our knowledge, this is the first time that hospital establishment of the EMRSA-16 clone in Spain has been reported. We have ensured the clonal nature of our isolates by development and integrative analyses of three different molecular approaches: pulsed-field gel electrophoresis, staphylococcal cassette chromosome mec (SCCmec) multiplex PCR assay, and multilocus sequence typing (1, 4, 5). Results from these analyses show that the clone is ST36-MRSA-II according to the nomenclature of Enright et al. (2) (UK-16 pulsotype, SCCmec type II, ST36). We have data from 1998 to 2002 that show how it started to colonize the hospital in 1999 and progressively displaced other MRSA clones, such as the Iberian one. At this time, the epidemic UK-16 clone constitutes 63.5% of the MRSA isolates of the hospital, and its spread has coincided with a substantial increase in the incidence of MRSA infections over the last 2 years (results not shown). Indeed, its high epidemicity is thought to be the key to its success in hospitals.
The fact that Tenerife Island is one of the most visited tourist destinations in Europe and has a very high rate of British arrivals each year emphasizes the need, recently pointed out, for closer international collaboration to monitor the spread of current epidemic strains as well as the emergence of new ones (4).
Acknowledgments
We thank Félix Claverie-Martín for his helpful critical input in the preparation of this letter.
This work was supported by grants 2001/020 from the Consejería de Educación, Cultura y Deportes, Canary Islands Autonomous Government, to S.M.-A., 2001/3150 from Fondo de Investigación Sanitaria, and BIO2002/00953 from Ministerio de Ciencia y Tecnología, Spanish Government, to S.M.-A. E.P.-R. was supported by a Ph.D. grant from Consejería de Educación, Cultura y Deportes, Canary Islands Autonomous Government. S.M.-A. was supported by Fondo de Investigación Sanitaria, Spain, contract 99/3060.
REFERENCES
- 1.Enright, M. C., N. P. Day, C. E. Davies, S. J. Peacock, and B. Spratt. 2000. Multilocus sequence typing for characterization of methicillin-resistant and methicillin-susceptible clones of Staphylococcus aureus. J. Clin. Microbiol. 38:1008-1015. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 2.Enright, M. C., D. A. Robinson, G. Randle, E. J. Feil, H. Grundmann, and B. Spratt. 2002. The evolutionary history of methicillin-resistant Staphylococcus aureus (MRSA). Proc. Natl. Acad. Sci. USA 99:7687-7692. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 3.Lowy, F. D. 1998. Staphylococcus aureus infections. N. Engl. J. Med. 339:520-532. [DOI] [PubMed] [Google Scholar]
- 4.Murchan, S., M. E. Kaufmann, A. Deplano, R. de Ryck, M. Struelens, C. E. Zinn, V. Fussing, S. Salmenlinna, J. Vuopio-Varkila, N. El Solh, C. Cuny, W. Witte, P. T. Tassios, N. Legakis, W. van Leeuwen, A. van Belkum, A. Vindel, I. Laconcha, J. Garaizar, S. Haeggman, B. Olsson-Liljequist, U. Ransjo, G. Coombes, and B. Cookson. 2003. Harmonization of pulsed-field gel electrophoresis protocols for epidemiological typing of strains of methicillin-resistant Staphylococcus aureus: a single approach developed by consensus in 10 European laboratories and its application for tracing the spread of related strains. J. Clin. Microbiol. 41:1574-1585. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 5.Oliveira, D. C., and H. de Lencastre. 2002. Multiplex PCR strategy for rapid identification of structural types and variants of the mec element in methicillin-resistant Staphylococcus aureus. Antimicrob. Agents Chemother. 46:2155-2161. [DOI] [PMC free article] [PubMed] [Google Scholar]