TABLE 1.

Irish MRSA isolates investigated from each study period and typed by MLST and SCCmec typing

Isolate phenotypeaNo. of isolates investigated in study periodb:No. of isolates typed by:
A (1971-75)B (1976-84)C (1985-87)D (1989)E (1992-93)F (1998)G (1999)H (2002)MLSTSCCmec typing
Early MRSA111
Phenotype II15515
Phenotype III111
AR01434
AR02333
AR05111
AR061441081127
AR07.0/07.222292717
AR07.3/07.4133299
AR09222
AR11414
AR13441532626
AR14441132222
AR15212
AR22212
AR23111
AR43202020
AR44222
ARNT (urea +ve)c12366
New01d111
New02d111
New03d2244
Unf01e111
Total in this study11511528177124130172
Total in original study2035067104321220714398NAfNA
  • a The most prevalent phenotypes during each study period are underlined. —, isolates exhibiting this phenotype were not recovered during the study period.

  • b Isolates from groups A to F were from Dublin; isolates in group G were from the North and South of Ireland; isolates in group H were from the South of Ireland. References for the original study with each group are as follows: group A (reference 5); B (5); C (4); D (39, 42); E (39, 42); F (42); G (3, 44); H (38, 43).

  • c No AR type could be assigned. PFGE analysis showed that most urease-positive isolates exhibiting the AR06 pattern yielded PFGE patterns unlike the patterns obtained from other AR06 isolates. Hence, assigning urease-positive AR06 isolates to AR type 06 was considered incorrect, and these isolates were assigned to no type (NT) pending PFGE, MLST, and SCCmec analysis.

  • d These isolates were not assigned an AR type because they produced unfamiliar AR patterns; the AR type is pending on the results of plasmid screening, enterotoxin profiling, PFGE, phage typing, biotyping, MLST, and SCCmec typing.

  • e This isolate yielded an unfamiliar AR pattern and was not assigned an AR type, pending the outcome of MLST and SCCmec typing results in this study.

  • f NA, not applicable.