MRSA bacteraemia: North/South Study of MRSA in Ireland 1999

Abstract

<h2>Abstract</h2> Retrospective aggregate data on all <i>Staphylococcus aureus</i> isolates recovered from blood cultures during 1998 were collected in both jurisdictions on the island of Ireland, Northern Ireland (North) and the Republic of Ireland (South), as part of the North/South Study of MRSA in Ireland 1999. A postal questionnaire was used to gather the data, and all diagnostic microbiology laboratories in the North and 98% of laboratories in the South participated. <i>S. aureus</i> bacteraemia occurred at rates of 20.4 per 100000 population in the North and 24.5 per 100000 in the South (missing data from one laboratory). In the North, 22% of patients who had blood cultures positive for <i>S. aureus</i> had methicillin-resistant <i>S. aureus</i> (MRSA) and 25% of <i>S. aureus</i> isolates were MRSA (some patients had more than one isolate). In the South, 31% of patients who had blood cultures positive for <i>S. aureus</i> had MRSA and 36% of <i>S. aureus</i> isolates were MRSA. There was a marked variation in rates between different regions. The percentage of patients with blood cultures positive for <i>S. aureus</i> that had MRSA was considerably lower in the North (22%) than in the South (31%), and in both jurisdictions was lower than that found in England and Wales in 1999 (37%). It is recommended that data on <i>S. aureus</i> bacteraemia and methicillin-resistance rates (already available in many laboratories) are gathered at regional and national level for the surveillance of antimicrobial resistance.