Large Burden of Community-Acquired Pneumonia Hospitalizations Among Older US Adults

New results from a prospective surveillance study published in the Journal of the American Medical Association indicate a significant burden of hospitalizations due to community-acquired pneumonia (CAP) among US adults, with the largest burden of disease found in adults ages 65 years or older. Furthermore, the investigators observed that a sizable portion of CAP was caused by Streptococcus pneumoniae, specifically from serotypes included in the 21-valent pneumococcal conjugate vaccine (PCV21; V116, Capvaxie; Merck).¹

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V116 Can Prevent Severe Illness, But Serotypes Still Infect Patients

Since 2024, following its approval by the FDA, V116 has been recommended by the Advisory Committee on Immunization Practices (ACIP) for adults ages 65 years and older and those with specific risk factors for the prevention of invasive pneumococcal disease and pneumonia due to Streptococcus pneumoniae. Clinical trials affirm the capability of V116 to demonstrate a robust immunogenic response in patients ages 18 to 64 years at heightened risk of pneumococcal infection.^2-4

Although the introduction of effective PCVs has drastically reduced the burden of pneumococcal disease and CAP, there is still a risk of Streptococcus pneumoniae serotypes not covered in a vaccine infecting individuals. It remains critical to properly monitor the burden of pneumococcal pneumonia in addition to the serotypes causing the illness. A myriad of challenges prevent such effective, thorough serotype monitoring from taking place, including pitfalls of traditional diagnostic techniques and highly sensitive pneumococcal cultures.¹

Novel techniques, including the use of serotype-specific urinary antigen detection (SSUAD) assays, have become helpful in identifying numerous pneumococcal serotypes in patients with noninvasive pneumonia. Use of SSUAD assays could allow for a more comprehensive assessment of the incidence of adult hospitalizations due to pneumonia. Therefore, the authors initiated a multicenter, prospective, active surveillance study to determine the incidence of hospitalizations for all-cause CAP, pneumococcal CAP, and pneumococcal CAP caused by serotypes included in the V116 vaccine.^1,5

Older Adults Remain Burdened by CAP Hospitalizations

This analysis was part of the ongoing Pneumococcal Pneumonia Epidemiology, Urine Serotyping, and Mental Outcomes (PNEUMO) program, which was designed by investigators at Vanderbilt University Medical Center to examine the epidemiology of hospitalizations due to CAP among adults. Participating hospitals identified adults hospitalized with clinical and radiographic evidence of CAP. Those enrolled between September 2018 and October 2022 were included in the analysis.¹

In total, 2016 patients hospitalized for all-cause CAP were included in the study population. According to the authors, the overall estimated annual incidence of hospitalizations due to all-cause CAP was 340 (95% CI, 323–358) per 100,000 adults. Notably, incidence was found to consistently increase with age. For pneumococcal CAP and pneumococcal CAP due to V116 serotypes, the annual incidence of hospitalizations was 43 (95% CI, 41-46) and 30 (95% CI, 29-32) per 100,000 adults, respectively.¹

The investigators also sought to determine the distribution of detected pneumococcal serotypes. Going by each included year in the study, SSUAD testing detected the most pneumococcal serotypes during year 1 of the study (100 serotypes), with the lowest during year 4 (28 serotypes). In the most recent study year (year 4), SSUAD testing detected 12 serotypes included in the 15-valent PCV (PCV15), 20-valent PCV (PCV20), and V116 vaccines; 4 serotypes not included in V116; 4 serotypes included in both PCV20 and V116; and 8 serotypes included in V116 but not in PCV15 or PCV20.1

Greater Uptake of V116 Could Prevent Hospitalizations

Ultimately, the authors determined that 14% of hospitalizations due to CAP had evidence of Streptococcus pneumoniae infection, and many detected pneumococcal serotypes corresponded to those included in the V116 vaccine. Furthermore, the incidence of CAP hospitalizations increased significantly with age. The data indicates a high burden of hospitalizations among older adults, but many of the serotypes causing these infections are covered in V116, necessitating greater vaccine proliferation and distribution.¹

A key aspect of this study was it taking place during the COVID-19 pandemic, which caused numerous disruptions across society and corresponding alterations in the circulation of respiratory illnesses. The authors noted that they maintained active surveillance throughout the pandemic, a key aspect of ensuring reliable results from this trial.¹

Pneumococcal CAP clearly remains a critical cause of hospitalizations, especially among older adults, in the US. Pharmacists and primary care providers should note the increased burden of hospitalizations among this population and target this group with interventions designed to increase uptake of a pneumococcal vaccine.¹

REFERENCES

1. Grijalva CG, Johnson KD, Resser JJ, et al. All-Cause and Pneumococcal Community-Acquired Pneumonia Hospitalizations Among Adults in Tennessee and Georgia. JAMA Netw Open. 2025;8(8):e2524783. doi:10.1001/jamanetworkopen.2025.24783

2. Gallagher A. FDA Approves V116 for Prevention of Invasive Pneumococcal Disease and Pneumonia. Pharmacy Times. Published June 18, 2024. Accessed August 7, 2025. https://www.pharmacytimes.com/view/fda-approves-v116-for-prevention-of-invasive-pneumococcal-disease-and-pneumonia

3. Halpern L. ACIP Votes to Recommend Pneumococcal 21-Valent Conjugate Vaccine for Adult Populations. Pharmacy Times. Published July 2, 2024. Accessed August 7, 2025. https://www.pharmacytimes.com/view/acip-votes-to-recommend-pneumococcal-21-valent-conjugate-vaccine-for-adult-populations

4. Halpern L. Pneumococcal 21-Valent Conjugate Vaccine Generates Positive Response in Adults at Increased Risk of Disease. Pharmacy Times. Published October 21, 2024. Accessed August 7, 2025. https://www.pharmacytimes.com/view/pneumococcal-21-valent-conjugate-vaccine-generates-positive-response-in-adults-at-increased-risk-of-disease

5. Wunderink RG, Self WH, Anderson EJ, et al. Pneumococcal Community-Acquired Pneumonia Detected by Serotype-Specific Urinary Antigen Detection Assays. Clin Infect Dis. 2018;66(10):1504-1510. doi:10.1093/cid/cix1066