TABLE 2.

Characteristics of the 20 human S. aureus isolates that were sent as DNA samples to the five participating laboratories in a blinded fashion and used as controls

Sample ID		Spa type (based on Sanger sequencing)	Comment/reference
Ring trial	Original
NGSRT01	00468	t011	Livestock-associated MRSA
NGSRT02	00551	t011	Livestock-associated MRSA, identical cgMLST genotype as NGSRT01
NGSRT03	01346	t011	Livestock-associated MRSA
NGSRT04	01354	t010	Classical hospital-acquired MRSA
NGSRT05	01360	t011	Livestock-associated MRSA, identical cgMLST genotype as NGSRT03
NGSRT06a	02180	t002	Central European community-acquired PVLb-positive MRSA
NGSRT07a	02482	t008	US typical community-acquired PVL-positive MRSA
NGSRT08a	02560	t044	Central European community-acquired PVL-positive MRSA
NGSRT09a	02638	t012	Classical hospital-acquired MRSA
NGSRT10a	02786	t843	mecC-positive MRSA
NGSRT11a	02949	t843	mecC-positive MRSA
NGSRT12a	02994	t003	Classical hospital-acquired MRSA
NGSRT13a	03039	t032	Classical hospital-acquired MRSA
NGSRT14a	COL	t008	MRSA strain COL
NGSRT15a	COL	t008	Duplicate of MRSA reference strain COL
NGSRT16	ATCC 25923	t021	MSSA quality control strain ATCC 25923
NGSRT17	P1	t001	Isolate P1 from reference 23
NGSRT18	P3	t001	Isolate P3 from reference 23
NGSRT19	P4	t001	Isolate P4 from reference 23, identical cgMLST genotype as NGSRT18
NGSRT20	P12	t001	Isolate P12 from reference 23

^aThese samples were separately cultivated, and DNA was extracted and sequenced as controls.

^bPVL, Panton-Valentine leukocidin.