Immunisation status and demographic characteristics of New Zealand infants at 1 year and 2 years of age.

AIMS To ascertain the immunisation status of a cohort of infants at 1 year and 2 years of age. METHODS The Plunket National Child Health Study is a longitudinal study of 4286 New Zealand children, based on an ethnically stratified and geographically representative sample of children born between 2 July 1990 and 30 June 1991. The immunisation status of these children was examined at 1 year and 2 years of age. RESULTS By 1 year and 2 years of age, 92.5% and 83.3%, respectively, had received all their age appropriate immunisations. Children who were incompletely immunised at 2 years of age were more likely to have mothers who were of high parity, or had higher or lower levels of education, or who had a later initial attendance at the doctor for this pregnancy, or who did not attend antenatal classes. The most common reason why immunisations had been delayed was because of ill health (of the children) at the time of the immunisation. Only 1.4% had had no immunisations at all by 2 years of age. CONCLUSIONS This study challenges the widely held views that New Zealand has a poor child health immunisation record, and that antiimmunisation beliefs are widespread. New Zealand needs systems in place which give current immunisation rates rather than relying on point prevalence or retrospective studies. Information about contraindications to immunisation needs to be reinforced with immunisation providers and advisors, and parents.