To protect people against serious infectious diseases,
children are vaccinated in the Netherlands from 2 months of age.
One of those diseases is pertussis. Pertussis is caused by a bacterium and can lead to an
acute and serious respiratory infection.
The bacterium is spread by coughing and can result in weeks or even in months of
prolonged coughing episodes which are very exhaustive for children.
Not, or not entirely, vaccinated babies are extra vulnerable,
and when they are infected, they are at risk to be admitted to the intensive care.
Despite vaccination, the number of pertussis cases in the Netherlands increased since 1996,
with the largest epidemic in 2012.
In other countries, this increase in pertussis notification is also reported.
The age at which pertussis prevalence is highest in the Netherlands,
was in 2001 in children 4 to 6 years of age.
To protect this group a booster vaccination against pertussis was
introduced in 2001 for children 4 years of age.
After this booster vaccination, the pertussis prevalence shifted to children
8 to 15 years of age.
The number of reported pertussis cases in adults increased as well.
Older children can still suffer from pertussis.
In some countries, like Germany, children aged 9 till 11 are being vaccinated with
an extra pertussis vaccine to protect this age group.
Whether this booster vaccination at 9 years of age provides long-term protection,
is yet unclear. The RIVM will develop a study to investigate the effect of
a booster vaccination against
pertussis in children 9 years of age. By vaccinating 9 year old children in this
study against pertussis,
three points will be investigated.
1, determine the level of protection against pertussis by vaccination.
2, assess if these children are better and prolonged protected against pertussis
and 3, evaluate on the long-term if such an extra vaccination can contribute
to a decline in pertussis transition to unvaccinated babies.