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O076 - EFFECTIVENESS AND IMPACT OF 13-VALENT PNEUMOCOCCAL VACCINES AGAINST INVASIVE DISEASE CAUSED BY SEROTYPE 3 PNEUMOCOCCUS: RESULTS OF SPIDNET, A EUROPEAN MULTICENTRE STUDY (2012-2019) (ID 561)
Serotype 3 is the second most frequent serotype causing invasive pneumococcal disease (IPD) in the European countries participating in the S. pneumoniae Invasive Disease network (SpIDnet). We measured the 13-valent conjugate vaccine (PCV13) effectiveness (VE) and impact (VI) of vaccination programmes using this vaccine on serotype 3 IPD.
We used the indirect cohort method to measure VE among 12-59-month-old children using data collected between 2012 and 2019 in nine SpIDnet sites. We calculated VE=(1-vaccination odds ratio)*100, adjusted for age, underlying conditions, notification year and site. Using surveillance data from five sites with PCV13 uptake >90%, we calculated site-specific incidence rate ratios (IRR) comparing serotype 3 IPD incidence in 2019 with the mean incidence during the PCV7 period by age group (<5, 5-64, 65+ years). We calculated VI=(1-pooled IRR)*100 using random effects meta-analysis.
PCV13 VE against serotype 3 IPD was 67% (95%CI: 38; 82) (cases/vaccinated=104/67; controls/vaccinated=875/813). In 2019, serotype 3 IPD incidence increased by 13% (-96 to 35) in children aged < 5 years, by 5% (-27 to 13) in 5-64 year-olds and by 8% (-7 to 25) in 65+ year-olds.
Our results suggest a moderate PCV13 effectiveness in children and no vaccine impact in the three age groups included after nine years of the vaccine use. This suggests no effect on the carriage of this serotype. Effectiveness against serotype 3 IPD and serotype 3 carriage needs to be improved in future vaccine formulations.
Acknowledgments: SpIDnet was funded by participating sites and European Centre for Disease Prevention and Control.