This depends on how old the child is and what immunisations have been missed.

If the immunisation schedule was not started when it should have been, immunisations can be started immediately with the normal time intervals between immunisations, e.g. the second DPT would follow 4 weeks after the first.

However, some immunisations may not be given as they are no longer needed or they are not safe in an older child:

• Pertussis vaccine is not given after 18 months.
• Hib and BCG are not given over 1 year.
• Measles need not be repeated if it is given after 18 months.

If immunisations were started correctly, but later immunisations were missed, these can be given using the normal time intervals between immunisations. If the immunisation schedule is interrupted it need not be started again from the beginning.