Abstract

The elderly and adults with medical risk conditions remain at high risk of invasive pneumococcal disease (IPD), highlighting the importance of adequate preventive efforts. In an observational population-based study in Norway (pop ≥ 5 years, 2009–2017) covering six years post-PCV13 implementation, we explored the incidence and risk of IPD associated with age and comorbidities. We obtained the data on 5535 IPD cases from the Norwegian Surveillance System for Communicable Diseases and the population data from Statistics Norway. To define comorbidities, we obtained ICD-10 codes from the Norwegian Patient Registry for the cases and the Norwegian population. The average annual decrease in PCV13 IPD incidence was significant in all risk groups and decreased post-PCV13 introduction by 16–20% per risk group, implying a nondifferential indirect protection from the childhood vaccination. The IPD incidence remained high in the medical risk groups. The relative importance of medical risk conditions was 2.8 to 6 times higher in those aged 5–64 versus ≥65 years for all types of IPD, since age itself is a risk factor for IPD. In groups without medical risk, the risk of IPD was eight times higher in those aged ≥65 compared to those 5–64 years (RR 8.3 (95% CI 7.3–9.5)). Our results underscore the need for age- and risk-group-based prevention strategies.

Highlights

  • Accepted: 18 August 2021Vaccination with pneumococcal conjugate vaccines (PCVs) in children has had a profound effect on the epidemiology of invasive pneumococcal disease (IPD) of both targeted and nontargeted age groups [1,2]

  • We extended the Norwegian part of the European studies to 2009–2017, including the six years post-PCV13 introduction to explore the impact and serotype distribution of IPD among medical risk groups and the elderly in a mature PCV13 program, and we were able to calculate incidence rates through inclusion of data on the size of the risk groups in the population

  • The PCV13 IPD incidence rate has become low in all groups, limiting the potential for prevention through PCV13 vaccination, whereas PPV23 serotypes still account for a substantial proportion of IPD in groups targeted for pneumococcal vaccination

Read more

Summary

Introduction

Accepted: 18 August 2021Vaccination with pneumococcal conjugate vaccines (PCVs) in children has had a profound effect on the epidemiology of invasive pneumococcal disease (IPD) of both targeted and nontargeted age groups [1,2]. Some previous studies have reported on the magnitude of the increased risk compared with the general population [5,9,10,11], they are limited by the data being from before 2013 [5,11,12], that the risk conditions are only presented in broad compound groups [9], or that they report from non-European settings [10] This renews the interest in exploring risk groups for IPD and the influence of various underlying medical conditions on the IPD epidemiology

Methods
Results
Discussion
Conclusion
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call