Incidence and clinical outcomes of pneumonia in persons with down syndrome in the United States.

BACKGROUND: Persons with Down syndrome (DS) experience an increased risk of pneumonia. We determined the incidence and outcomes of pneumonia and relationship to underlying comorbidities in persons with and without DS in the United States. METHODS: This retrospective matched cohort study used de-identified administrative claims data from Optum. Persons with DS were matched 1:4 to persons without DS on age, sex, and race/ethnicity. Pneumonia episodes were analyzed for incidence, rate ratios and 95 % confidence intervals, clinical outcomes, and comorbidities. RESULTS: During 1-year follow-up among 33796 persons with and 135184 without DS, the incidence of all-cause pneumonia (pneumonia) was substantially higher among people with DS than those without DS (12427 vs. 2531 episodes/100000 person-years; 4.7-5.7 fold increase). Persons with DS and pneumonia were more likely to be hospitalized (39.4 % vs. 13.9 %) or admitted to the ICU (16.8 % vs. 4.8 %). Mortality was higher 1 year after first pneumonia (5.7 % vs. 2.4 %; P < 0.0001). Results were similar for episodes of pneumococcal pneumonia. Specific comorbidities were associated with pneumonia, particularly heart disease in children and neurologic disease in adults, which only partially mediated the effect of DS on pneumonia. CONCLUSIONS: Among persons with DS, incidence of pneumonia and associated hospitalizations were increased; mortality among those with pneumonia was comparable at 30 days, but higher at 1 year. DS should be considered an independent risk condition for pneumonia.

Misdiagnosis of Clostridioides difficile Infections by Standard-of-Care Specimen Collection and Testing among Hospitalized Adults, Louisville, Kentucky, USA, 2019-20201.

Although Clostridioides difficile infection (CDI) incidence is high in the United States, standard-of-care (SOC) stool collection and testing practices might result in incidence overestimation or underestimation. We conducted diarrhea surveillance among inpatients >50 years of age in Louisville, Kentucky, USA, during October 14, 2019-October 13, 2020; concurrent SOC stool collection and CDI testing occurred independently. A study CDI case was nucleic acid amplification test‒/cytotoxicity neutralization assay‒positive or nucleic acid amplification test‒positive stool in a patient with pseudomembranous colitis. Study incidence was adjusted for hospitalization share and specimen collection rate and, in a sensitivity analysis, for diarrhea cases without study testing. SOC hospitalized CDI incidence was 121/100,000 population/year; study incidence was 154/100,000 population/year and, in sensitivity analysis, 202/100,000 population/year. Of 75 SOC CDI cases, 12 (16.0%) were not study diagnosed; of 109 study CDI cases, 44 (40.4%) were not SOC diagnosed. CDI incidence estimates based on SOC CDI testing are probably underestimated.

Hospital discharge diagnosis position: impact on adult pneumonia burden estimates.

OBJECTIVES: Pneumonia hospitalization studies using administrative claims rely on pneumonia coded in the first discharge diagnosis field over pneumonia in any coded field, and few have evaluated disposition following discharge. This study reports the total disease burden and discharge disposition among patients with pneumonia coded in any diagnosis field. STUDY DESIGN: Retrospective database review. METHODS: Data from the 2014 National Inpatient Sample of the Healthcare Cost and Utilization Project, a population-weighted, 20% sample of all US community hospitalizations, were analyzed for all pneumonia hospitalizations in adults aged 18 to 64 years and 65 years or older. Number of hospitalizations, hospital stay length, direct medical costs, in-hospital mortality, patient discharge disposition, illness severity, and likelihood of dying were evaluated based on the diagnosis field of pneumonia as a discharge diagnosis (eg, first, second, third, or further). RESULTS: In 2014, an estimated 2.4 million US adult hospitalizations were associated with pneumonia in any of the discharge diagnosis positions (33%-35% in first, 33%-36% in second, and 29%-34% in further positions). When estimates were based only on hospitalizations with pneumonia in the first diagnosis field, approximately 66% of hospitalizations, 78% of hospital days, 87% of in-hospital deaths, 76% and 73% of transfers to short-term hospitals and skilled nursing facilities, 68% of discharges with home health care services, and 82% of direct medical costs were excluded. CONCLUSIONS: Pneumonia hospitalizations were associated with substantial health care resource utilization and in-hospital mortality. Relying only on pneumonia in the first hospital diagnosis field may potentially underestimate the burden associated with pneumonia hospitalizations.

The epidemiologic and biologic basis for classifying older age as a high-risk, immunocompromising condition for pneumococcal vaccine policy.

INTRODUCTION: Immunosenescence is a normal biologic process involving deterioration of protective immune responses. Consequently, older adults experience increased risk of infectious diseases, particularly pneumonia, and its leading bacterial cause, Streptococcus pneumoniae. Pneumococcal vaccine recommendations are often limited to adults with specific medical conditions despite similar disease risks among older adults due to immunosenescence. AREAS COVERED: This article reviews epidemiologic, biologic, and clinical evidence supporting the consideration of older age due to immunosenescence as an immunocompromising condition for the purpose of pneumococcal vaccine policy and the role vaccination can play in healthy aging. EXPERT OPINION: Epidemiologic and biologic evidence suggest that pneumococcal disease risk increases with age and is comparable for healthy older adults and younger adults with immunocompromising conditions. Because immunocompromising conditions are already indicated for pneumococcal conjugate vaccines (PCVs), a comprehensive public health strategy would also recognize immunosenescence. Moreover, older persons should be vaccinated before reaching the highest risk ages, consistent with the approach for other immunocompromising conditions. To facilitate PCV use among older adults, vaccine technical committees (VTCs) could classify older age as an immunocompromising condition based on the process of immunosenescence. With global aging, VTCs will need to consider immunosenescence and vaccine use during healthy aging.

One-Year Quality of Life Post-Pneumonia Diagnosis in Japanese Adults.

BACKGROUND: Pneumonia is a common, serious illness in the elderly, with a poorly characterized long-term impact on health-related quality of life (HRQoL). The Japanese Goto Epidemiology Study is a prospective, active, population-based surveillance study of adults with X-ray/CT scan-confirmed community-onset pneumonia, assessing the HRQoL outcome quality-adjusted life-years (QALYs). We report QALY scores and losses among a subset of participants in this study. METHODS: QALYs were derived from responses to the Japanese version of the EuroQol-5D-5L health-state classification instrument at days 0, 7, 15, 30, 90, 180, and 365 after pneumonia diagnosis from participants enrolled from June 2017 to May 2018. We used patients as their own controls, calculating comparison QALYs by extrapolating EuroQol-5D-5L scores for day -30, accounting for mortality and changes in scores with age. RESULTS: Of 405 participants, 85% were aged ≥65 years, 58% were male, and 69% were hospitalized for clinically and radiologically confirmed pneumonia. Compliance with interviews by patients or proxies was 100%. Adjusted EuroQol-5D-5L scores were 0.759, 0.561, 0.702, and 0.689 at days -30, 0 (diagnosis), 180, and 365, respectively. Average scores at all time points remained below the average day -30 scores (P ≤ .001). Pneumonia resulted in a 1-year adjusted loss of 0.13 QALYs (~47.5 quality-adjusted days) (P < .001). CONCLUSIONS: Substantial QALY losses were observed among Japanese adults following pneumonia diagnosis, and scores had not returned to prediagnosis levels at 1 year postdiagnosis. QALY scores and cumulative losses were comparable to those in US adults with chronic heart failure, stroke, or renal failure.

County-level Predictors of Coronavirus Disease 2019 (COVID-19) Cases and Deaths in the United States: What Happened, and Where Do We Go from Here?

BACKGROUND: The United States has been heavily impacted by the coronavirus disease 2019 (COVID-19) pandemic. Understanding microlevel patterns in US rates of COVID-19 can inform specific prevention strategies. METHODS: Using a negative binomial mixed-effects regression model, we evaluated the associations between a broad set of US county-level sociodemographic, economic, and health status-related characteristics and cumulative rates of laboratory-confirmed COVID-19 cases and deaths between 22 January 2020 and 31 August 2020. RESULTS: Rates of COVID-19 cases and deaths were higher in US counties that were more urban or densely populated or that had more crowded housing, air pollution, women, persons aged 20-49 years, racial/ethnic minorities, residential housing segregation, income inequality, uninsured persons, diabetics, or mobility outside the home during the pandemic. CONCLUSIONS: To our knowledge, this study provides results from the most comprehensive multivariable analysis of county-level predictors of rates of COVID-19 cases and deaths conducted to date. Our findings make clear that ensuring that COVID-19 preventive measures, including vaccines when available, reach vulnerable and minority communities and are distributed in a manner that meaningfully disrupts transmission (in addition to protecting those at highest risk of severe disease) will likely be critical to stem the pandemic.

Streptococcus pneumoniae serotype distribution and antimicrobial nonsusceptibility trends among adults with pneumonia in the United States, 2009‒2017.

Background In the United States, the 13-valent pneumococcal conjugate vaccine has been recommended for children since 2010 and for adults aged ≥65 years since 2014. We assessed S. pneumoniae antimicrobial nonsusceptibility among adults with suspected pneumonia from hospital settings. Methods Isolates were collected from 105 US sites between 2009 and 2017 in the SENTRY Antimicrobial Surveillance Program. Clinical and Laboratory Standards Institute methods were used for susceptibility testing. Serotypes were determined by cpsB sequence obtained by PCR or whole genome sequencing, plus multiplex PCR and/or Neufeld Quellung reactions as needed. Findings Of 7254 S. pneumoniae isolates analyzed, 63.6% and 36.4% were from patients aged 18‒64 and ≥65 years, respectively. Among all isolates, penicillin and ceftriaxone nonsusceptibility declined by 72.3% and 73.8%, respectively, with smaller changes observed for other antibiotics. Nonsusceptibility patterns were serotype-specific; for example, nonsusceptibility was relatively stable for serotype 19A but declined for 19F. Simultaneously, the percentage of serotype 19A isolates decreased from 17.4% to 3.9%, whereas for serotype 19F this percentage increased from 2.8% to 5.0%. The percentage of serotype 3 isolates that were nonsusceptible increased for select antibiotic classes, and the percentage of serotype 3 among all isolates increased minimally from 10.2% to 11.8%. Interpretation Overall pneumococcal nonsusceptibility patterns were influenced by distinct patterns within serotypes, indicating the likelihood of serotype-specific resistance mechanisms. Serotype 19A observations were consistent with vaccine-induced reductions in circulation with no change in the organism susceptibility, whereas the nonsusceptibility increases for serotypes 3 and 19F may indicate circulation of more antibiotic-resistant clones.

Diabetes mellitus as a vaccine-effect modifier: a review.

INTRODUCTION: Diabetes mellitus (DM) is a highly prevalent, chronic condition in adults worldwide. Little is known about the potential role of diabetes as an effect modifier of vaccine protective responses. AREAS COVERED: We conducted a literature review of the immunogenicity, efficacy and effectiveness of immunization in individuals, in studies that compared subjects with DM (DM+) and without DM (DM-). We found few published studies, which were only for vaccines against hepatitis B, influenza, pneumococcal disease, or varicela zoster. Except for a consistent attenuation of the immune response to hepatitis B vaccine among DM+ individuals, we found little other consistent evidence for DM as an effect modifier of vaccine responses. EXPERT OPINION: There are substantial gaps in our knowledge of the impact of DM on the immune response to immunization or effect of vaccination.

Lessons from mass vaccination response to meningococcal B outbreaks at US universities.

College students in the United States are at an increased risk for meningococcal serogroup B disease or MenB, which causes the majority of invasive meningococcal disease in the country among adolescents and young adults (62%) and also across all age groups (36%) as of 2018. Approximately one-third of MenB cases among college students occur during campus outbreaks, which trigger substantial public health concern and costs associated with conducting rapid mass vaccination campaigns in an emergency setting. Eleven US college outbreaks of MenB disease have occurred since the initial licensure and recommendation of two MenB vaccines in 2014/2015; both vaccines have been used as part of outbreak responses on campuses, but vaccine coverage and multidose series completion among the general adolescent population are very low (approximately 17% of 17-year-olds in the United States received ≥1 dose in 2018). This review recounts shifts in US meningococcal outbreak epidemiology, lessons from immunogenicity evaluations of MenB vaccines with outbreak strains, and recent college outbreak experiences and mass vaccination responses. The challenges of reactive MenB outbreak containment and potential benefits of preventive immunization of US adolescents are also considered.

US College Students Are at Increased Risk for Serogroup B Meningococcal Disease.

Publicly available surveillance data, Centers for Disease Control and Prevention reports, and other sources suggest that college students in the United States are at increased risk for meningococcus serogroup B (MenB) disease. US surveillance data from 2015 to 2017 show that the incidence of invasive meningococcal disease (IMD) was greater among college students than among those not attending college; the average annual incidence of MenB disease was >5-fold higher among college students, and all college IMD outbreaks between 2011 and March 2019 were caused by MenB.

Rates of hospitalization for community-acquired pneumonia among US adults: A systematic review.

BACKGROUND: Community-acquired pneumonia (CAP) is associated with significant disease burden in adults but has not been measured uniformly. Reconciling differences across studies is critical for understanding the true burden of CAP. METHODS: We performed a systematic literature review of the incidence of hospitalized CAP among US adults and described the impact of key study characteristics on these estimates. RESULTS: After review of 8361 articles as of January 31, 2019, we identified 28 studies with 41 unique estimates of hospitalized CAP incidence. Among adults ≥65 years of age, annual rates of hospitalized CAP ranged from 847 to 3500 per 100,000 persons with median = 1830. Rates were lower in studies that excluded patients with healthcare-associated (but community-onset) pneumonia (HCAP; median = 2003 vs 1286; P = 0.02) or immunocompromising conditions (median = 1895 vs 1409; P = 0.27) compared to those that did not. Rates of CAP were also lower in studies that used more restrictive criteria for diagnosing pneumonia (eg, pneumonia coded in any diagnosis position [median = 2270] vs pneumonia coded in the first position only [median = 1375] in studies of administrative claims; P = 0.02). For adults <65 years of age, rates of CAP were lower (range: 89 to 1138 per 100,000; median = 199). CONCLUSIONS: CAP causes a significant disease burden among adults, particularly among those ≥65 years of age. Commonly-applied exclusion criteria (eg, persons with HCAP or immunocompromising conditions) or restrictive case definitions (eg, only including pneumonias coded in the primary diagnosis position) have led to systematic underestimation of CAP incidence in many previous studies. In studies that did not apply these restrictive criteria, the rate of hospitalization was approximately 2000 per 100,000 annually. Understanding the true burden of adult CAP is critical for highlighting the ongoing need for expanded prevention programs, including vaccination.

Meningococcal vaccination: a discussion with all adolescents, whether college-bound or not.

Introduction: Adolescents and young adults are the primary reservoirs and transmitters of meningococci. In the US, meningococcal serogroup B (MenB) disease predominates over A, C, W, and Y; ACIP-recommended MenACWY and MenB vaccines are available. We investigated invasive meningococcal disease (IMD) burden and vaccination among non-college adolescents.Methods: IMD incidence by college attendance status and vaccination rates were analyzed using publicly available surveillance data.Results: 64/158 IMD cases occurred in non-college 18-24-year-olds during 2015-2017. Among non-college cases, the MenACWY vaccination rates were 38%-57% vs 90%-100% among college cases when vaccination status was known; MenB vaccination was 0% vs 0%-7%, respectively. In 2018, 17.2% of all 17-year-olds received ≥1 dose of multidose MenB vaccines; ≤50% completed the series.Conclusion: Meningococcal vaccination is emphasized for college-bound adolescents, but non-college adolescents bear much of the disease burden. Low vaccine receipt preserves their risk, underscoring the need to protect all adolescents through vaccination.

Pneumococcal conjugate vaccine against serotype 3 pneumococcal pneumonia in adults: A systematic review and pooled analysis.

BACKGROUND: Serotype 3 pneumococcal disease has not substantially declined at the population level after the routine introduction of 13-valent pneumococcal conjugate vaccine (PCV13) into pediatric immunization programs across the globe. This epidemiological finding has generated debate regarding the effectiveness of PCV13 against serotype 3 disease. Evaluating PCV13 effectiveness against serotype 3 is especially critical in adults, where serotype 3 makes up an important amount of remaining pneumococcal disease. METHODS: We performed a systematic review of the published literature to assess the direct effectiveness of PCV13 against serotype 3 community-acquired pneumonia (CAP) among adults. We then estimated overall vaccine effectiveness (VE) using a pooled analysis of the individual-level, raw data. RESULTS: Two published studies met inclusion criteria. One was a randomized controlled trial conducted in the Netherlands and published in 2014. The other was a recently-published case-control study conducted in Louisville, Kentucky that used a test-negative design (TND). We also identified a third TND study conducted in Argentina that was recently presented as a conference abstract but is not yet published. All three studies were conducted in adults aged ≥65 years. PCV13 VE against serotype 3 hospitalized CAP was 52.5% (95%CI: 6.2-75.9%) from the pooled analysis of individual-level data from all three studies. Results were similar if the unpublished estimate was excluded (serotype 3 VE = 53.6% [95%CI: 6.7-76.9%]). No heterogeneity was observed. CONCLUSIONS: Currently-available evidence, although limited to three studies, suggests that PCV13 provides direct protection against serotype 3 hospitalized CAP in adults aged ≥65 years.

Pneumococcal epidemiology among us adults hospitalized for community-acquired pneumonia.

BACKGROUND: Few studies have measured the burden of adult pneumococcal disease after the introduction of 13-valent pneumococcal conjugate vaccine (PCV13) into the US infant vaccination schedule. Further, most data regarding pneumococcal serotypes are derived from invasive pneumococcal disease (IPD), which represents only a fraction of all adult pneumococcal disease burden. Understanding which pneumococcal serotypes cause pneumonia in adults is critical for informing current immunization policy. The objective of this study was to measure the proportion of radiographically-confirmed (CXR+) community-acquired pneumonia (CAP) caused by PCV13 serotypes in hospitalized US adults. METHODS: This observational, prospective surveillance study recruited hospitalized adults aged ≥18 years from 21 acute care hospitals across 10 geographically-dispersed cities in the United States between October 2013 and September 2016. Clinical and demographic data were collected during hospitalization. Vital status was ascertained 30 days after enrollment. Pneumococcal serotypes were detected via culture from the respiratory tract and normally-sterile sites (including blood and pleural fluid). Additionally, a novel, Luminex-based serotype-specific urinary antigen detection (UAD) assay was used to detect serotypes included in PCV13. RESULTS: Of 15,572 enrolled participants, 12,055 eligible patients with CXR+CAP were included in the final analysis population. Mean age was 64.1 years and 52.7% were aged ≥65 years. Common comorbidities included chronic obstructive pulmonary disease (43.0%) and diabetes mellitus (28.6%). PCV13 serotypes were detected in 552/12,055 (4.6%) of all patients and 265/6347 (4.2%) of those aged ≥65 years. Among patients aged 18-64 years PCV13 serotypes were detected in 3.8-5.3% of patients depending on their risk status. CONCLUSIONS: After implementation of a pneumococcal conjugate vaccination program in US children, and despite the herd protection observed in US adults, a persistent burden of PCV13-type CAP remains in this population.

Disparities in uptake of 13-valent pneumococcal conjugate vaccine among older adults in the United States.

BACKGROUND: In September 2014, 13-valent pneumococcal conjugate vaccine (PCV13) was universally recommended for all US adults aged ≥65 years. Adult PCV13 coverage, including whether disparities in uptake exist, however, is not well-described. METHODS: We used a monthly series of cross-sectional analyses of administrative medical and prescription claims data collected by IQVIA and linked to sociodemographic data collected by Experian to estimate overall and subpopulation-level uptake of PCV13 among US adults aged ≥65 years. RESULTS: Among adults aged ≥65 years, 43.3% received PCV13 by the end of November 2017. Race/ethnicity, annual household income, education status, and neighborhood urbanicity were strongly related to PCV13 uptake among adults aged ≥65 years. Lower uptake of PCV13 was observed for non-Hispanic black (36.3%) and Hispanic (30.0%) adults (vs 45.6% for non-Hispanic whites, P < .01), the poor (30.7% vs 54.2% among lowest vs highest income deciles, P < .01), adults with low educational status (33.0% vs 49.0% among those without high school education vs college educated, P < .01), and those living in rural communities (22.9%) or urban/inner-city (33.8%) areas (vs 45.8% in suburban areas, P < .01). CONCLUSIONS: PCV13 uptake among adults aged ≥65 occurred rapidly in the three years after universal recommendation in September 2014. Yet, poor and minority communities, rural and urban/inner-city areas, and communities with low educational attainment had substantially lower PCV13 coverage. These same populations are at increased risk of pneumococcal disease. In order to maximize the benefits of pneumococcal vaccination, further targeted and tailored interventions to increase PCV13 uptake in these underserved populations are still necessary.

Decision-making for PCV in adults.

Thirteen-valent pneumococcal conjugate vaccine (PCV13) was licensed in adults to address the unmet medical need of vaccine-type community acquired pneumonia (CAP) and the limitations of previous plain-polysaccharide vaccines. Since then, some have questioned the utility of adult PCV13 use, arguing that: i) high PCV13 uptake in young children would provide indirect effects that, by themselves, would sufficiently protect unvaccinated adults and ii) no data describing the real-world effectiveness of PCV13 use in adults, especially with immunocompromising conditions, exist. Even in countries like the United States where PCV13 has been routinely recommended for all adults aged ≥ 65 years, the recommendation is contingent on a re-evaluation to determine if continued use is needed in the context of a mature PCV13 pediatric immunization program. Emerging evidence, however, suggests that i) a meaningful burden of PCV13-type pneumococcal pneumonia still persists in adults at increased risk for pneumococcal disease, despite indirect effects from long-standing pediatric PCV13 use, ii) adult PCV13 use is effective and has reduced pneumococcal CAP, even in the elderly and those with chronic medical or immunocompromising conditions - and disease could come back if PCV13 were removed, and iii) ethical and pragmatic vaccine policy considerations support continued adult PCV13 use in countries that have already introduced the vaccine (eg, disparities in adult PCV13 uptake, confusion stemming from removing a previously-recommended vaccine for a non-safety-related concern, and the reality that next-generation PCVs are only a few years away). Together, these findings suggest that continued PCV13 vaccination in adults is needed to control vaccine-type CAP.

Acute otitis media, antimicrobial prescriptions, and medical expenses among children in the United States during 2011-2016.

INTRODUCTION: We analyzed outpatient visits, incidence, antimicrobial prescriptions, and medical expenditures for acute otitis media (AOM) in the United States during 2011-2016. METHODS: Data sources included the National Disease and Therapeutic Index (NDTI™) projections by IQVIA (for AOM cases), The Medical Expenditure Panel Survey (for medical expenditures) and the US Census (for population estimates). Analyses focused on children aged ≤9 years between 2011 and 2016. We used the 2014 medical expenditure estimate per otitis media episode ($520) as proxy for all years. RESULTS: In 2011, there were an estimated 11.5 million AOM episodes in children aged 0-9 years in the US with AOM incidence rates (IR) of 476, 204, and 284 episodes per 1000 children aged 0-2, 3-9, and 0-9 years, respectively. All subsequent years had lower IRs, and by 2016, IR was 25.1% lower than in 2011 in children 0-9 years. In addition, there were estimates of 10.8 million and 9.2 million fewer cumulative AOM episodes and antimicrobial prescriptions for AOM nationwide between 2012 and 2016, compared to annual 2011 estimates, representing a ∼$5.6 billion decrease in direct medical expenditures. The average number of antibiotic prescriptions per AOM visit remained stable with 0.89 and 0.86 prescriptions per visit in 2011 and 2016, respectively. CONCLUSIONS: AOM incidence, antimicrobial prescriptions, and associated medical expenses decreased substantially between 2011 and 2016 in the United States. Antimicrobial prescribing practices remain unchanged. Additional studies are warranted to assess causality.

Effectiveness of 13-Valent Pneumococcal Conjugate Vaccine Against Hospitalization for Community-Acquired Pneumonia in Older US Adults: A Test-Negative Design.

Background: Following universal recommendation for use of 13-valent pneumococcal conjugate vaccine (PCV13) in US adults aged ≥65 years in September 2014, we conducted the first real-world evaluation of PCV13 vaccine effectiveness (VE) against hospitalized vaccine-type community-acquired pneumonia (CAP) in this population. Methods: Using a test-negative design, we identified cases and controls from a population-based surveillance study of adults in Louisville, Kentucky, who were hospitalized with CAP. We analyzed a subset of CAP patients enrolled 1 April 2015 through 30 April 2016 who were aged ≥65 years and consented to have their pneumococcal vaccination history confirmed by health insurance records. Cases were defined as hospitalized CAP patients with PCV13 serotypes identified via culture or serotype-specific urinary antigen detection assay. Remaining CAP patients served as test-negative controls. Results: Of 2034 CAP hospitalizations, we identified PCV13 serotypes in 68 (3.3%) participants (ie, cases), of whom 6 of 68 (8.8%) had a positive blood culture. Cases were less likely to be immunocompromised (29.4% vs 46.4%, P = .02) and overweight or obese (41.2% vs 58.6%, P = .01) compared to controls, but were otherwise similar. Cases were less likely to have received PCV13 than controls (3/68 [4.4%] vs 285/1966 [14.5%]; unadjusted VE, 72.8% [95% confidence interval, 12.8%-91.5%]). No confounding was observed during adjustment for patient characteristics, including immunocompromised status, body mass index, and history of influenza and pneumococcal polysaccharide vaccination (adjusted VE range, 71.1%-73.3%). Conclusions: Our study is the first to demonstrate real-world effectiveness of PCV13 against vaccine-type CAP in adults aged ≥65 years following introduction into a national immunization program.

Post hoc analysis of the efficacy of the 13-valent pneumococcal conjugate vaccine against vaccine-type community-acquired pneumonia in at-risk older adults.

BACKGROUND: Individuals with certain chronic medical conditions are at higher risk of developing pneumonia and pneumococcal disease than those without. Using data from the Community-Acquired Pneumonia Immunization Trial in Adults (CAPiTA), this post hoc analysis assessed the efficacy of the 13-valent pneumococcal conjugate vaccine (PCV13) in adults aged ≥65 years with at-risk conditions. METHODS: The Community-Acquired Pneumonia Immunization Trial in Adults (CAPiTA) was a double-blind, parallel-group, randomized, placebo-controlled study in the Netherlands in which adults aged ≥65 years received either PCV13 or placebo. Outcomes of interest were identified using prespecified clinical criteria, radiographic confirmation, routine microbiologic testing, and a serotype-specific urinary antigen detection assay. In this post hoc analysis, participants were classified by at-risk status based on self-reporting of any of the following chronic medical conditions: heart disease, lung disease, asthma, diabetes, liver disease, and smoking. The objective of this analysis was to assess PCV13 vaccine efficacy (VE) against a first episode of vaccine-serotype community-acquired pneumonia (VT-CAP) in at-risk participants. RESULTS: Of the 84,496 adults enrolled in the study, 41,385 (49.2%) were considered at risk owing to chronic medical conditions. Of the 139 VT-CAP cases, 115 (82.7%) occurred in these participants. VE of PCV13 against a first episode of VT-CAP among participants with at-risk conditions was 40.3% (95.2% CI: 11.4%, 60.2%). Average duration of follow-up since vaccination was 3.95 years for at-risk participants; protection did not wane over the study period. CONCLUSIONS: This post hoc analysis of the Community-Acquired Pneumonia Immunization Trial in Adults (CAPiTA) showed significant and persistent efficacy of PCV13 against VT-CAP in at-risk older adults. ClinicalTrials.gov identifier: NCT00744263.

Pneumococcal conjugate vaccine use for the prevention of pneumococcal disease in adults <50 years of age.

INTRODUCTION: Adults, particularly those with underlying chronic conditions, eg, cardiovascular, liver, and pulmonary diseases and diabetes mellitus, have a persistent pneumococcal disease burden. Thirteen-valent pneumococcal conjugate vaccine (PCV13) is recommended in the United States for all adults aged ≥65 years and immunocompromised adults aged <65 years to protect against vaccine-serotype (VT) invasive pneumococcal disease (IPD) and pneumonia. PCV13 is not recommended for immunocompetent adults aged ≥18 years with comorbidities associated with increased pneumococcal disease risk. AREAS COVERED: This US-focused review summarizes PCV13-type IPD and community-acquired pneumonia burden in adults aged <50 years, PCV13 immunogenicity and safety in this population, and adult pneumococcal vaccination recommendations. EXPERT COMMENTARY: Considering (i) PCV13 has demonstrated efficacy against VT-IPD and pneumonia in adults aged ≥65 years (with or without underlying chronic conditions), and (ii) immune responses to PCV13 in younger adults are comparable or better than in older adults, PCV13 would likely have similar efficacy in adults aged <50 years. Recommending PCV13 for at-risk adults aged <50 years would provide direct immunologic benefit of a conjugate vaccine and could address an important unmet medical need for pneumococcal pneumonia prevention. Although not directly addressed here, this benefit would likely extend to at-risk adults aged 50-64 years.