Childhood Pneumonia Hospitalizations Fell Sharply After PCV13 Introduction

Rates of all-cause hospitalized pneumonia (AC-hPNA) among children in the United States fell by 51% to 57% across all age groups in the decade following the 2010 recommendation for routine childhood vaccination with the 13-valent pneumococcal conjugate vaccine (PCV13), according to a retrospective cohort study published in Vaccines.¹

Using claims data from more than 10 million children, researchers found that hospitalization rates nonetheless remained several-fold higher among children with underlying medical conditions and that disparities persisted for Black children younger than 2 years, lower-income children aged 2 to 5 years, and middle-income children aged 6 to 17 years.¹

The study drew on claims data from Optum's de-identified Clinformatics Data Mart Database, spanning January 2008 through December 2019. The analysis included 9.4 million children younger than 18 years, contributing 10.1 million unique qualifying periods of continuous healthcare coverage. Approximately 26% were younger than 2 years, 14% were aged 2 to 5 years, and 60% were aged 6 to 17 years.¹

Researchers identified episodes of AC-hPNA from inpatient admissions with a diagnosis of pneumonia in the principal position or respiratory failure in the principal position paired with pneumonia in the secondary position. Rates were calculated across 4 periods—pre-PCV13 (2008-2009), peri-PCV13 (2010-2012), post-PCV13#1 (2013-2016), and post-PCV13#2 (2017-2019)—and stratified by age, race, comorbidity profile, and annual household income (HHI).¹

Sharp Declines in Hospitalizations, But Persistent Gaps

AC-hPNA rates declined across every age group studied. Among children younger than 2 years, rates fell from 410.2 per 100,000 person-years (95% CI, 391.7-429.5) in the pre-PCV13 period to 177.0 per 100,000 person-years (95% CI, 165.4-189.4) in the post-PCV13#2 period, an incidence rate ratio (IRR) of 0.43 (95% CI, 0.40-0.47) corresponding to a 57% relative reduction.¹

Among children aged 2 to 5 years, rates dropped from 265.6 (95% CI, 254.9-276.7) to 129.0 (95% CI, 122.3-136.0) per 100,000 person-years, an IRR of 0.49 (95% CI, 0.45-0.52) and a 51% relative reduction. Children aged 6 to 17 years saw rates fall from 63.0 (95% CI, 60.1-65.9) to 30.0 (95% CI, 28.3-31.9) per 100,000 person-years, an IRR of 0.48 (95% CI, 0.44-0.51) and a 52% relative reduction.¹

Declines occurred across all race, comorbidity, and HHI subgroups, with IRRs during the post-PCV13#2 period (vs pre-PCV13) ranging from 0.37 (95% CI, 0.27-0.49) to 0.63 (95% CI, 0.49-0.81), or relative reductions of 37% to 63%. Even so, comorbidity profile drove the largest remaining disparity. During the post-PCV13#2 period, AC-hPNA incidence among at-risk children was 5.04 times higher (95% CI, 4.07-6.24) than among low-risk children aged younger than 2 years, 5.64 times higher (95% CI, 4.84-6.57) among those aged 2 to 5 years, and 8.84 times higher (95% CI, 7.75-10.08) among those aged 6 to 17 years.¹

Smaller but statistically significant disparities also persisted by race and income. Among children younger than 2 years, AC-hPNA incidence was 1.43 times higher (95% CI, 1.05-1.97) among Black children compared with white children. Among children aged 2 to 5 years, incidence was 1.24 times higher (95% CI, 1.04-1.49) among those with an HHI below $50,000 compared with those at $100,000 or above, and among children aged 6 to 17 years, incidence was 1.21 times higher (95% CI, 1.04-1.41) among those with an HHI of $50,000 to $99,999 compared with the highest-income group.¹

The authors cautioned that the observed declines are likely multifactorial and may not be entirely attributable to PCV13, potentially also reflecting changes in practice patterns and expanded in-home medical services. Because the study measured all-cause rather than pneumococcal-specific pneumonia, it could not isolate the vaccine's precise contribution.¹

What This Means for Pharmacists

The Advisory Committee on Immunization Practices first recommended the 7-valent pneumococcal conjugate vaccine for children younger than 5 years in 2000, followed by PCV13 in 2010. Further, 15-valent (PCV15) and 20-valent (PCV20) conjugate vaccines joined the childhood schedule in 2022 and 2023. Current CDC guidance calls for a 4-dose series of PCV15 or PCV20 at 2, 4, 6, and 12 through 15 months, and children who started their series with PCV13 can complete it with PCV15 or PCV20 without restarting.^1,2

The American Academy of Pediatrics likewise recommends routine vaccination for all infants and children aged 2 to 59 months, with additional doses for children aged 2 to 18 years who have high-risk conditions—now expanded to include moderate to severe persistent asthma, chronic liver disease, and chronic kidney disease—and credits PCV introduction since 2000 with what it calls a "dramatic decline" in invasive pneumococcal disease.³

The study authors pointed to EHR-based reminder and recall systems to support vaccine series completion in at-risk children, community partnerships to reach populations with persistently high disease burden, and efforts to reduce structural barriers such as transportation and clinic access as potential strategies to close the remaining gaps.¹

Pharmacists who administer or recommend vaccines are positioned to help close these gaps, but a separate systematic review of 24 studies found that pharmacists' knowledge of pneumococcal vaccination is often unsatisfactory—ratings of "good knowledge" ranged from 39.02% to 68.2% depending on the study and threshold used—and that pharmacists recommended pneumococcal vaccination to patients less consistently than influenza vaccination, with recommendation rates across studies ranging from 45.3% to 66.6%.⁴

REFERENCES

1. Rozenbaum MH, Averin A, Weycker D, et al. Residual Disparities in US Children Hospitalized Due to All-Cause Pneumonia Following Implementation of Childhood PCV13 in National Immunization Program. Vaccines (Basel). 2026;14(8):679. Published 2026 Aug 6. doi:10.3390/vaccines14080679

2. Centers for Disease Control and Prevention. Recommended vaccines for children. CDC. February 25, 2026. Accessed September 2, 2026. https://www.cdc.gov/pneumococcal/vaccines/children.html

3. American Academy of Pediatrics. Pneumococcal vaccines. AAP. October 9, 2025. Accessed September 2, 2026. https://www.aap.org/en/patient-care/immunizations/pneumococcal-vaccines/

4. Waszkiewicz M, Wnuk K, Świtalski J, Augustynowicz A. Knowledge, attitudes, and beliefs of pharmacists regarding vaccinations against influenza and pneumococci - a systematic review. Hum Vaccin Immunother. 2025;21(1):2489889. doi:10.1080/21645515.2025.2489889