Table 1.

Study subjects and their vaccination status prior to study initiation.

Subject number*	Age	Sex	Previous Hib vaccinations (year)
2	32	F	None
9	33	M	None
11	44	F	None
12	30	M	ProHIBiT® (Berna, 1991, 2 shots)
21	31	F	None
22	45	M	None

*Numbers are not consecutive, as these volunteers were part of a cohort receiving different vaccines. Subjects included in this study are not reflecting a selection, but include all subjects receiving the ActHIB vaccine. Vaccinations and collection of blood were done in March 2020.