Table 2.

Schedule of blood samples for immunology substudy (subset of groups V–Z)

Age (months)	2 months	3 months	12 months	Post-12 months*	24 months
Subgroup a			V-Y†	V-Y	V-Y
Sample volume			7.5 mL	2 mL	3.5 mL
Assays			ELISA, B cell	ELISA	ELISA
Subgroup b	V	W-Y	V-Y	V-Y
Sample volume	2 mL	2 mL	2 mL	7.5 mL
Assays	ELISA	ELISA	ELISA	ELISA, B cell
Subgroup c			V-Y	V-Y	V-Y
Sample volume			3.5 mL	7.5 mL	3.5 mL
Assays			ELISA	ELISA, B cell	ELISA
Subgroup d			V–Y	V–Y	V–Y
Sample volume			3.5 mL	3.5 mL	7.5 mL
Assays			ELISA, OPA‡	ELISA, OPA	ELISA, B cell
Subgroup Z-I					Z
Sample volume					3.5 mL
Assays					ELISA

*The post-12 months blood sample is collected at 12 months plus 7 days in subgroups a and b and at 12 months plus 28 days in subgroups c and d.

†3.5 mL sample for ELISA only in group W.

‡OPAs not performed in group W.

OPA, opsonophagocytic assay.