Table 1.

Source of E. coli strains used in this study; adapted from Hurrel et al. [19]

MLST sequence type	Strain number	Location recovered from NGT	Hospital	Date of isolation	Neonate	Feeding source	Duration (h)	Oral antibiotics given	Gastric pH	Age (wk)	Frequency of feeding
ST2076	1047	Biofilm	1	22/10/2007	116	RTF	12–18	No	4.5	2–3	Every 2 h
	1050	Lumen			116
	1051	Lumen			116
ST73	1009	Biofilm	2	05/06/2007	101	BMF	>48	No	4.0	>4	Every 2 h
	1010	Biofilm		12/06/2007	102	BMF	12–18	No	NG	>4	Every 2 h
	1015	Biofilm		12/06/2007	104	BM	24–48	No	3.5	3–4	Every 2 h
	1016	Lumen			104
ST95	904	Biofilm	2	24/04/2007	55	BM,IF	24–48	Yes	4.5	3–4	Every 3 h
	905	Lumen			55
	926	Biofilm		01/05/2007	61	BMF, RTF	6–12	No	NG	>4	Cont.
	927	Lumen			61
	929	Biofilm		01/05/2007	62	PIF	>48	No	5	>4	Cont.
	933	Lumen			62
	934	Biofilm		01/05/2007	63	RTF	18–24	No	3.5	3–4	Every 3 h
	910	Biofilm		03/05/2007	64	BMF, RTF	>48	No	4	1–2	Every 2 h
	912	Lumen			64
	913	Biofilm		03/05/2007	65	RTF	24–28	No	5.5	>4	Cont.
	917	Lumen			65
	923	Biofilm		08/05/2007	67	BMF	12–18	No	2.5	1–2	Every 2 h
	924	Lumen			67
	937	Lumen		08/05/2007	68	BMF, RTF	18–24	Yes	NG	3–4	Every 2 h
	939	Biofilm		08/05/2007	69	BMF	<6	No	4.5	1–2	Every 2 h
	943	Biofilm		08/05/2007	70	RTF, Th	24–48	No	4.0	>4	Every 2 h
	944	Lumen			70
	947	Lumen		08/05/2007	71	PIF, Th	<6 h	No	3.5	>4	Every 4 h
	949	Biofilm			71
ST127	780	Biofilm	2	16/01/2007	4	BM	18–24	No	3.5	>4	Every 2 h
	796	Biofilm		30/01/2007	17	BM, PIF	6–12	No	3–3.5	>4	Every 2 h
	786	Biofilm		17/02/2007	37	BMF, PIF, Th	18–24	No	4	>4	Every 3 h
ST394	1008	Lumen	2	06/06/2007	99	BMF, RTF, Th	>48	No	4.5	2–3	Every 3 h

Duration Period of time NG tube in place, BM Breast milk, NG Not given, BMF breast milk fortified, Cont. continuous feed, PIF reconstituted powdered infant formula, NGT nasogastric tube, IF infant formula, no further description given, RTF ready to feed formula, Th thickener added to feed