Emerging Infectious Disease ISSN: 1080-6059

Isolate Removal Methods and Methicillin-resistant Staphylococcus aureus Surveillance

Fenfang Li*

, Tracy L. Ayers†, Sarah Y. Park†, F. DeWolfe Miller*, Ralph MacFadden†, Michele Nakata†, Myra Ching Lee†, and Paul V. Effler†

Author affiliations: *University of Hawaii School of Medicine, Honolulu, Hawaii, USA; †Hawaii Department of Health, Honolulu, Hawaii, USA

Effect of duplicate isolate removal on Staphylococcus aureus susceptibility to oxacillin, by clinical setting*

Method	ICU		Non-ICU		Outpatient
Method	No. isolates	No. susceptible (%, 95% CI)	No. isolates	No. susceptible (%, 95% CI)	No. isolates	No. susceptible (%, 95% CI)
No removal	843	465 (55, 52–59)	3,894	1,971 (51, 49–52)	9,858	7,281 (74, 73–75)
Cerner, 3 d	712	387 (54, 51–58)	3,363	1,705 (51, 49–52)	9,590	7,101 (74, 73–75)
NCCLS, 3 d	708	384 (54, 51–58)	3,328	1,682 (51, 49–52)	9,559	7,078 (74, 73–75)
Cerner, 10 d	629	355 (56, 53–60)	3,090	1,614 (52, 50–54)	9,500	7,045 (74, 73–75)
NCCLS, 10 d	616	352 (57, 53–61)	3,038	1,584 (52, 50–54)	9,461	7,020 (74, 73–75)
Cerner, 30 d	589	345 (59, 55–63)	2,849	1,569 (55, 53–57)	9,280	6,907 (74, 74–75)
NCCLS, 30 d	574	341 (59, 55–63)	2,772	1,534 (55, 53–57)	9,222	6,875 (75, 74–75)
Most resistant	545	317 (58, 54–62)	2,426	1,355 (56, 54–58)	8,427	6,295 (75, 74–76)
Cerner, 90 d	574	339 (59, 55–63)	2,681	1,525 (57, 55–59)	8,905	6,667 (75, 74–76)
NCCLS, 90 d	558	335 (60, 56–64)	2,563	1,480 (58, 56–60)	8,802	6,617 (75, 74–76)
Cerner, 365 d	564	336 (60, 56–64)	2,578	1,485 (58, 56–60)	8,589	6,444 (75, 74–76)
NCCLS, 365 d	545	332 (61, 57–65)	2,426	1,420 (59, 57–60)	8,427	6,368 (76, 75–76)
Most susceptible	545	334 (61, 57–65)	2,426	1,468 (61, 59–62)	8,427	6,433 (76, 75–77)

*d, days; ICU, intensive care unit; NCCLS, National Committee for Clinical Laboratory Standards; CI, confidence interval.