Vaccination protocol: first six months of life
| Vaccination | Birth | One month | Two months | Four months | Six months |
| IPV | X1-150 | X | X | ||
| OPV | X | X | |||
| HBV | X | X | X | ||
| DTP | X | X | X | ||
| HiB | X | X |
↵1-150 Only study group A received IPV at birth.
IPV, enhanced inactivated poliovirus vaccine, one ampoule intramuscularly (RIVM, Bilthoven, Holland); OPV, oral poliovirus vaccine, two drops by mouth (SmithKline Beecham, Rixemsart, Belgium); HBV, hepatitis B vaccine, 0.5 ml (10 μg/0.5 ml) intramuscularly (Engerix; SmithKline Beecham, Belgium); DTP, diphtheria-tetanus-pertussis vaccine, 0.5 ml intramuscularly (Pasteur Merieux, Lyon, France); HiB, Haemophilus influenzaeB vaccine intramuscularly (H-B-VAX; Merck, Sharp and Dohme, West Point, USA).