TABLE 2.

Ambler classification for clinical and challenge isolates

Group	CPO detect result	No. of isolates that were:					Total
		Class A	Class B	Class D	Indeterminate	CPO negative
All isolates	Class A	122	0	4	7	4	137
	Class B	3	126	3	1	12	145
	Class D	0	2	134	10	6	152
	Indeterminate	18	27	10	9a	12	76
	Negative	3	6	0	1	932	942
Total		146	161	151	28	966	1,452
Enterobacterales isolates	Class A	106	0	0	7	0	113
	Class B	3	81	1	0	9	94
	Class D	0	2	97	5	1	105
	Indeterminate	15	18	2	1	11	47
	Negative	3	1	0	1	735	740
Total		127	102	100	14	756	1,099

^aOne of these indeterminate results was for an Enterobacterales isolate.