Increasing Rates of Invasive Pneumococcal Disease in Children Vaccinated Against Streptococcus pneumoniae, 2017-2024
TL;DR
There is a significant increase in IPD among older children (> 5 Y) and adolescents who received PCV13 at the authors' hospital, and the need for ongoing surveillance and perhaps updated vaccination recommendations for children is highlighted.
Abstract
Streptococcus pneumoniae (SP) is the leading cause of bacterial pneumonia and pneumonia-related deaths in children <5 years of age. Routine immunization with pneumococcal conjugated vaccines (PCV) has led to a decrease in rates of invasive pneumococcal disease (IPD). The CDC reports a 95% drop in IPD in children <5 Y (1998-2021), including a 99% decrease by serotypes included in PCV13. Recently, we observed increasing IPD rates in otherwise healthy children (≥5 years), an age group which is not routinely surveyed for IPD. Identify and compare children IPD, stratified by age during 3 periods: before/during/after the COVID-19 pandemic, emphasizing risk factors and completeness of PCV. Retrospective analysis of children with IPD (1/2017-12/2024) using electronic medical records (EMR); IPD is defined as patient (<19Y) hospitalized with confirmation of SP isolated from a normally sterile body site. SP isolates from 1/2023-1/2025 were molecularly characterized (whole genomic sequencing for serotyping and virulence factors). Descriptive statistics on the following population characteristics were examined for frequencies and comparisons between IPD and non-hospitalized SP cases: Demographic (age, race, sex, insurance type, completeness of PCV and DTaP); clinical conditions and culture results including antimicrobial susceptibility; variables stratified by age group (< 5Y to > 5Y). Serotyped isolates were analyzed for presence within PCV 13. Bivariate logistic regression to assess association between IPD and completeness of PCV will be done, and those factors determined a priori for SP carriage or infection will be determined; multivariate logistic regression will then be conducted to assess the association between IPD and age, adjusted for those risk factors. All tests for significance will be based on a p-value of < 0.05. There is a significant increase in IPD among older children (> 5 Y) and adolescents who received PCV13 at our hospital. From 228 IPD cases (2021-2024), there were 58 hospital admissions post pandemic in 2023 alone, compared to a collective of 48 admissions in 2020-2022. 133 (58.3%) patients > 5 years old and 52 (23%) were < 2 years of age. Patient racial identities were 58% Black and 25% White. The most common IPD diagnosis was sepsis (52%), followed by pneumonia and meningitis. The rates and severity of infections are similar to those <5 years. (11 isolates (1/2023-12/2024) are available for serotyping and WGS.) The persistent increasing trend of IPD in older children and adolescents highlights the need for ongoing surveillance and perhaps updated vaccination recommendations for children.