IPD is the world’s number one vaccine-preventable cause of death among preschoolers at the moment.
Last year alone, it killed 41 infants in New Zealand.
The disease is caused by the common bacteria, Streptococcus pneumoniae.
At the minor end of the scale, it can cause localised ear or sinus infections.
But IPD occurs if the bacteria gets into the blood, resulting in a severe form of pneumonia, bacteraemia (blood infection) or meningitis, also potentially affecting the heart muscle, joints and abdomen.
Also of concern, treatment can be compromised due to rising rates of antibiotic resistance.
While New Zealand’s immunisation schedule included a PVC13 vaccine from 2014-17, Pharmac reverted to a 10-valent pneumococcal vaccine (PVC10) in 2017, because of low IPD case numbers at the time and to redirect funding into other vaccines.
However, new research from the University of Otago (Christchurch), shows IPD cases rose sharply in New Zealand preschool children between 2017 and 2021, particularly cases of the potentially life-threatening 19A IPD serotype.
New Zealand’s proportion of serotype 19A IPD cases increased from 11.5% to 29.5% for children under 5.
University of Otago paediatric infectious diseases specialist and study co-author Tony Walls said the World Health Organisation recommended a switch in the vaccine used in any national PVC programme should be considered, if the epidemiology of IPD changed significantly.
"This study, the first undertaken comparing IPD rates in both New Zealand and Australia, proves that significant change was occurring in New Zealand, and that an upgrade to the PVC13 vaccine was urgently required."
Late last year, in response to concerns about rising case numbers, Pharmac amended the national childhood immunisation schedule to include a 13-valent pneumococcal vaccine (PVC13).
Prof Walls said their research backed Pharmac’s decision to upgrade the vaccine from the existing 10-valent to a 13-valent vaccine.
However, he warned the recent switch may take a few years to significantly reduce the burden of the disease.
"Catch-up immunisations for children under 5 are not part of the PVC programme change, therefore those who received PVC10 may not have adequate protection against serotype 19A."
University of Auckland Immunisation Advisory Centre (IMAC) medical director Nikki Turner advised parents to consider getting their children the PVC13 vaccine — particularly infants under 1.
"For older children, up to the age of 5, yes, they may benefit from an extra dose of PVC13, but it’s not funded."
Children up to 5 were also now eligible for the funded meningococcal B vaccine, measles vaccine and flu vaccine, Prof Turner said.
The study authors said improving immunisation coverage nationwide, particularly in high-risk groups, should be a key aspect of any plan to reduce the impact of IPD due to serotype 19A.
