BREAKTHROUGH IPD FOLLOWING 13VPCV SCHEDULE CHANGE FROM 3+0 TO 2+1 AMONG AUSTRALIAN CHILDREN (ID 921)
- Sanjay Jayasinghe, Australia
- Sanjay Jayasinghe, Australia
- Ross Andrews, Australia
- Kristine Macartney,
- Christopher C. Blyth, Australia
Abstract
Background
In mid-2018, the Australian infant 13vPCV schedule changed from three primary doses (3+0) to two primary doses and a 12 month booster (2+1) to address increasing breakthrough cases of invasive pneumococcal disease (IPD), predominantly in children >12 months. We assess the impact of this schedule change on breakthrough IPD.
Methods
All cases of breakthrough IPD following 13vPCV (2012-2018) reported to the national notifiable diseases surveillance system were analysed by age, serotype and clinical syndrome. In addition, cases in the first 3 quarters post-schedule change were compared to corresponding period pre-change.
Results
Annual 13vPCV breakthrough case counts in children aged <5yrs (figure) increased progressively from 2012(n=3) to 2017(n=73) but declined in 2018 (n=65). Of 306 total cases, 297 were caused by serotypes 3(41%),19A(38%) and 19F(19%). Those aged 12-24 months accounted for 41% (n=125) of cases. Over two thirds of cases (n=211) were pneumonia and 12 were meningitis. Breakthrough cases in children aged >12 months post-schedule change were still more than that in the comparison pre-change period (41 versus 31).
Conclusions
The change to administer the third scheduled PCV dose as a booster (2+1)is expected to reduce breakthrough IPD by improving both direct and indirect protection from 13vPCV but discernible impact is not yet observed.