In July 2010 a Strategy Workshop was convened to review New Zealand pertussis epidemiology and the Global Pertussis Initiative immunisation strategies. The meeting was co-chaired by the Ministry of Health with GlaxoSmithKline (GSK) providing the venue and some travel support.

Attendees included delegates from district health boards (DHBs), Environmental Science and Research (ESR), RNZCGP and the Ministry of Health’s Immunisation Technical Forum.

It has become increasingly clear that achieving high childhood immunisation coverage alone does not completely protect infants from pertussis. Both natural and vaccine derived immunity are not lifelong, lasting only a few years. This means that older siblings, adult household members and other adults, such as grandparents, with a cough illness can be a source of infection for those too young to have completed primary immunisation.1,2 At least 8% of adults with a cough illness of more than 7 days duration are likely to have pertussis.3 The source of infection of infants hospitalised with pertussis, when it can be identified, is usually an older household member, most commonly the mother.4

The Global Pertussis Initiative (GPI) addressed how best to control pertussis and described seven key strategies to improve pertussis control. These are:

New Zealand already has the three routine childhood vaccination strategies recommended by the GPI, namely an infant immunisation programme, a four year old childhood booster dose and an adolescent dose. Coverage for the infant schedule in New Zealand is increasing and now 90%, though only approximately one-half of children receive their immunisations on time, within four weeks.

Data on the coverage of the 4-year and 11-year booster doses are lacking. The recent epidemiology suggests that improved vaccination coverage has had an impact on the incidence of pertussis with the current epidemic not reaching the heights of prior epidemics.

Following presentations to set the scene and detailed discussion the key recommendations of the forum were to improve delivery of the current immunisation programme ensuring that 95% if infants received 3 doses of a pertussis containing vaccine by 6 months of age, to fund DHBs to offer pertussis immunisation to healthcare workers.

In particular, those who work with neonates and young children should receive a pertussis containing vaccine every 10 years and to pilot the promotion of cocoon immunisation around newborns. This would involve ensuring that, on diagnosis of pregnancy, all other children in the household are up-to-date with their immunisation schedules, immunising all mothers after birth unless a dose of a pertussis containing vaccine has been received within the last 10 years and providing information to new parents to encourage grandparents and other household and regular contacts to be immunised.

Universal adult immunisation and immunisation of childcare workers were not supported, at present, by the forum.

These recommendations, with greater supporting detail, have been forwarded to the Ministry of Health for consideration. A full report is available from Dr Stewart Reid at the email address below.