The vaccine against Poliomyelitis is mandatory.By the age of 8 weeks it is normal to start the vaccination against: polio, diphtheria, tetanus, pertussis (whooping cough), meningitis, hepatitis B, pneumonia, and pneumococcal infection. By the age of 1 it is recommended to start the vaccination against measles, mumps, and rubella (German measles). By the age of 13/15 months it is recommended to start the vaccination against meningitis C. Some of these vaccinations will need to be renewed later on.
A time schedule of the common vaccines:
http://www.kindengezin.be/img/oktober2015vaccinatieschema.pdf