Polysaccharide conjugate vaccine against pneumococcal pneumonia in adults

Closer adult child-parent relations the stronger the vaccine hesitancy: A cross-sectional study of adult Children's attitudes toward pneumococcal vaccination of elderly parents and its determinants in Guangzhou, China

Pneumococcal disease (PD) has a serious effect on older people aged 60 years and above. However, pneumococcal vaccination rates for older people in China remain low. This study aimed to explore adult children's perspectives on the vaccination of their parents and to examine the determinants of vaccine hesitancy. In October 2022, a cross-sectional survey was conducted in Guangzhou, China. The questionnaire assesses data on the sociodemographic characteristics of adult children and their parents, health beliefs about vaccination, and variables measuring adult child-parent relationships. Adult child-parent relationships types were identified by Latent Class Analysis (LCA). Binary logistic regression was employed to examine the factors associated with vaccine hesitancy. A total of 1,597 respondents were enrolled in the study, and 59.8% of the adult children expressed hesitancy about vaccinating their elderly parents. The LCA model identified three distinct types of adult child-parent relations: detached, intimate but distant, and tight-knit. Binary logistic regression analyses revealed that respondents with intimate but distant (OR = 3.04) and tight-knit (OR = 3.01) adult child - parent relationships, high literacy (OR = 2.63), and high perceived barriers of vaccine (OR = 1.18) were more likely to be hesitant. Conversely, those with high income (OR = 0.35) and parents with difficulties in activities of daily living (OR = 0.44) were less likely to exhibit vaccine hesitancy. Close adult child-parent relations were positively associated with vaccine hesitancy. Health education related to the vaccination of older persons should be extended to adult children.

Health and economic impact of the 21-valent pneumococcal conjugate vaccine (V116) for adults in Japan: a delta price approach

INTRODUCTION

This study analyzed the health and economic impact of the 21-valent pneumococcal conjugate vaccine (V116) and the 20-valent pneumococcal conjugate vaccine (PCV20), as well as their relative cost-effectiveness, in Japanese adults aged 65 years using a delta pricing approach.

METHODS

A Markov model was employed to simulate the movement of the Japanese population among four health states: healthy, pneumococcal disease (consisting of invasive pneumococcal disease [IPD] with or without meningitis and non-bacteremic pneumococcal pneumonia [NBPP]), post-meningitis sequelae, and death. The model was populated with publicly available demographic and epidemiologic data, stratified by risk level. Pneumococcal serotype distribution and vaccine effectiveness, as well as direct and indirect treatment costs and health-related utilities, were derived from published sources. The model used a lifetime horizon and 2% discounting of costs and life-years. Costs were adjusted to 2023 values in Japanese yen (¥). Outcomes were cases and deaths, life-years and quality-adjusted life-years (QALYs), vaccination and treatment costs, and incremental cost-effectiveness ratios. The range over which V116 was cost-saving and cost-effective was determined.

RESULTS

Compared to PCV20, V116 averted an additional 28 cases of IPD, 918 cases of NBPP, 5 deaths from IPD, and 51 deaths from NBPP over the lifetime of a single age 65 cohort. Life-years and QALYs gained were 1,019 and 642, respectively, relative to PCV20; V116 saved ¥733 million in direct medical costs and ¥557 million in indirect costs, compared to PCV20. V116 was found to be cost-saving at price premiums up to ¥1,322 (payer perspective) or ¥2,327 (societal perspective) and remained below a willingness-to-pay threshold of ¥5 million/QALY for premiums up to ¥7,113 (payer perspective) or ¥8,117 (societal perspective).

CONCLUSIONS

V116 is projected to provide more population health benefits in Japan than PCV20, and to be cost-effective at a variety of price premiums.

Pneumococcal vaccines in China

Invasive pneumococcal disease (IPD) is a serious global public health problem and the leading cause of morbidity and mortality in children and adults in China. Thus, developing and administering pneumococcal vaccines are important for disease prevention. The PPV23 and PCV13 vaccines are available in the Chinese market and are primarily produced by domestic manufacturers. The potential risk of increased IPD caused by non-vaccine serotypes should be considered. Here, we review the current status of IPD, pneumococcal vaccines, and their quality control in China. We also address the challenges and future directions for making progress in controlling IPD, emphasizing the need for further evaluation of the disease burden and monitoring the effectiveness of vaccination efforts.

Systematic literature review of cost-effectiveness analyses of adult 15- and 20-valent pneumococcal vaccines

BACKGROUND

The economic and public health benefits of adult pneumococcal vaccines vary across countries due to different epidemiology and costs. We systematically reviewed and summarized findings and assumptions of cost-effectiveness analyses (CEA) of the recently introduced 15- and 20-valent pneumococcal conjugate vaccines (PCV15 and PCV20) in adults.

METHODS

We performed a systematic search for CEA studies of PCV15 and/or PCV20 versus existing strategies via PubMed, EMBASE, CEA Registry, EconLit, HTA Database, and NITAG resource center through April 23, 2024. Study characteristics, methods, assumptions, and findings were extracted independently by two reviewers; quality was assessed using ECOBIAS. Results were synthesized qualitatively to summarize key attributes and conclusions.

RESULTS

Of 137 identified records, 26 studies were included; the majority (24/26) concerned high-income countries. All employed static Markov-type models comparing higher-valent PCVs used alone or in combination with 23-valent pneumococcal polysaccharide vaccine (PPSV23) to current recommendations (PPSV23 alone, PCV13 alone, PCV13 + PPSV23, no vaccination). Most studies (22/26) concluded PCV20 used alone was cost-saving (dominant) or cost-effective compared to other adult pneumococcal strategies (PPSV23 alone, PCV13 ± PPSV23, PCV15 ± PPSV23, or no vaccination). PCVs were generally assumed to have serotype-specific effectiveness equal to PCV13 efficacy in the pivotal trial, though four studies used estimates from a Delphi panel; protection was assumed to last between 10 and 20 years. PPSV23 was assumed to have lower effectiveness against non-bacteremic pneumonia and shorter duration of protection. Herd effects from higher-valent PCVs in childhood (12/26), serotype replacement (2/26), or both (1/26) were included in half (13/26) of studies, which attenuated adult vaccine impact. Most studies were assessed as low risk of bias; five abstracts did not provide sufficient information for assessment.

CONCLUSION

Current evidence indicates that 20-valent PCV used alone is likely to be cost-effective or dominate other adult pneumococcal strategies. Future research is needed to address remaining uncertainties in assumptions and to support evidence-based policymaking.

Adult vaccinations against respiratory infections

INTRODUCTION

Lower respiratory infections have a huge impact on global health, especially in older individuals, immunocompromised people, and those with chronic comorbidities. The COVID-19 pandemic highlights the importance of vaccination. However, there are lower rates of vaccination in the adult population that are commonly due to a missed opportunity to vaccinate. Vaccination offers the best strategy to prevent hospitalization, complications, and death caused by lower respiratory infections.

AREAS COVERED

In this review, the authors provide an overview of the vaccines for lower respiratory infections in the adult population. The review highlights the available data about the impact of vaccines on preventing respiratory infections, focusing on the pneumococcal vaccine, influenza vaccine, COVID-19 vaccines, and respiratory syncytial virus (RSV) vaccines. The authors discuss the currently available scientific evidence on the role of vaccines against respiratory infections. Finally, the authors review the current recommendations for vaccines in the adult population.

EXPERT OPINION

Scientific evidence on the effectiveness of vaccines against respiratory infections is important. An efficient implementation of adult immunization strategies will provide an opportunity to decrease the global burden of lower respiratory infections. Recognizing the existing vaccines and their recommendations for the adult population is essential to achieve a high vaccination rate in the population.

Vaccination against Respiratory Infections in the Immunosenescent Older Adult Population: Challenges and Opportunities

Respiratory infections are associated with a huge burden of disease every year and disproportionately affect older adults, namely those aged 65 years and older. Older adults are at increased risk of infections compared with their younger counterparts, and once infected, have a higher risk of experiencing severe disease course, complications, and long-term sequelae. Therefore, vaccination is clearly a key strategy to prevent infection and its attendant negative consequences. We review here the burden of common respiratory diseases in older adults, namely influenza, pneumococcal disease, and respiratory syncytial virus. We then review some of the challenges facing immunization of older adults, namely immunosenescence, inflammaging, and low vaccine uptake. Next, potential opportunities for overcoming these challenges are reviewed, including the use of higher antigen doses and/or adjuvants in vaccine formulations for older adults, and the potential of multiomics analyses to improve development, performance, and implementation of vaccines.

Update on the evolving landscape of pneumococcal capsule types: new discoveries and way forward

SUMMARYStreptococcus pneumoniae (the "pneumococcus") is a significant human pathogen. The key determinant of pneumococcal fitness and virulence is its ability to produce a protective polysaccharide (PS) capsule, and anti-capsule antibodies mediate serotype-specific opsonophagocytic killing of bacteria. Notably, immunization with pneumococcal conjugate vaccines (PCVs) has effectively reduced the burden of disease caused by serotypes included in vaccines but has also spurred a relative upsurge in the prevalence of non-vaccine serotypes. Recent advancements in serotyping and bioinformatics surveillance tools coupled with high-resolution analytical techniques have enabled the discovery of numerous new capsule types, thereby providing a fresh perspective on the dynamic pneumococcal landscape. This review offers insights into the current pneumococcal seroepidemiology highlighting important serotype shifts in different global regions in the PCV era. It also comprehensively summarizes newly discovered serotypes from 2007 to 2024, alongside updates on revised chemical structures and the de-novo determinations of structures for previously known serotypes. Furthermore, we spotlight emerging evidence on non-pneumococcal Mitis-group strains that express capsular PS that are serologically and biochemically related to the pneumococcal capsule types. We further discuss the implications of these recent findings on capsule nomenclature, pneumococcal carriage detection, and future PCV design. The review maps out the current status and also outlines the course for future research and vaccine strategies, ensuring a continued effective response to the evolving pneumococcal challenge.

Cost-effectiveness of 15-valent or 20-valent pneumococcal conjugate vaccine for U.S. adults aged 65 years and older and adults 19 years and older with underlying conditions

BACKGROUND

In June 2021, the Advisory Committee on Immunization Practices (ACIP) recommended use of either 20-valent pneumococcal conjugate vaccine (PCV20) alone or 15-valent pneumococcal conjugate vaccine (PCV15) in series with 23-valent pneumococcal polysaccharide vaccine (PPSV23) for all PCV-unvaccinated adults aged ≥65 years (age-based) and for adults aged 19-64 years with conditions that increase the risk for pneumococcal disease (risk-based). This recommendation replaced a previous recommendation for PPSV23 with or without 13-valent pneumococcal conjugate vaccine (PCV13) for these groups.

OBJECTIVE

We conducted a cost-effectiveness analysis of age-based and risk-based use of either PCV15 in series with PPSV23 or PCV20 alone when compared to previous recommendations.

METHODS

We utilized probabilistic cohort models of all 65-year-olds (age-based) and 19-year-olds (risk-based through age 64 years and age-based at age 65 years). A spreadsheet-based Monte Carlo simulation software was used to estimate immunization costs, medical costs, non-medical costs, and overall disease burden under different vaccine strategies. The model tracked inpatient invasive pneumococcal disease (IPD) and non-bacteremic pneumonia (NBP) in inpatient and outpatient settings. One-way sensitivity analyses incorporated indirect effects of prospective pediatric vaccination with PCV15 and PCV20 on adult IPD and NBP incidence. Costs were reported in 2021 US dollars. All future costs and outcomes were discounted at 3 % per year.

RESULTS

Age-based use of either PCV20 alone or PCV15 in series with PPSV23 at age 65 years were both shown to be cost-saving (improved health outcomes and saved costs). Combined cost-effectiveness of risk-based (19-64 years) plus age-based (65 years) (risk-and-age-based) use of PCV20 alone was cost-saving, whereas use of PCV15 in series with PPSV23 increased quality-adjusted life years (QALYs) but cost $412,111 (95 % CI: 270,295, 694,869) per QALY gained.

CONCLUSION

In U.S. adults, replacing the previous recommendations with PCV20 alone or PCV15 in series with PPSV23 improved health outcomes. Except for risk-and-age-based use of PCV15 in series with PPSV23 that resulted in increased cost per QALY gained, the interventions also reduced costs.

Vaccination Against Influenza and Pneumococcus During Pretravel Health Consultations in the United States: Interventions and Missed Opportunities

Background

Infections by Streptococcus pneumoniae and influenza viruses are vaccine-preventable diseases causing great morbidity and mortality. We evaluated pneumococcal and influenza vaccination practices during pre-international travel health consultations.

Methods

We evaluated data on pretravel visits over a 10-year period (1 July 2012 through 31 June 2022) from 31 sites in Global TravEpiNet (GTEN), a consortium of US healthcare facilities providing pretravel health consultations. Data were collected using an online structured questionnaire utilized by GTEN providers. We obtained summary statistics and performed multivariable logistic regression models to identify characteristics associated with receiving the vaccinations.

Results

At 116 865 pretravel visits, 28 754 (25%) travelers were eligible to receive pneumococcal vaccination and 56 150 (48%) travelers were eligible to receive influenza vaccination. A total of 19 557 (68%) pneumococcal vaccine-eligible travelers were not offered the vaccine at the pretravel visit. Among influenza vaccine-eligible travelers, 8592 (15%) were not offered the vaccine, and an additional 16 931 (30%) travelers declined the vaccine. Influenza vaccine was not available for 8014 (14%) eligible travelers. Nonadministration of the influenza vaccine was most frequent in the months of April through September. Compared to nonacademic centers or centers in the South or Midwest, travelers seen in academic centers or centers in the Northeast were more likely to receive either vaccine.

Conclusions

Increasing awareness of global influenza transmission patterns and improving access to routine vaccines at the pretravel encounter may enhance vaccination for respiratory pathogens in departing US international travelers.

Streptococcus pneumoniae Serotype Distribution Among US Adults Hospitalized With Community-Acquired Pneumonia, 2019-2020

Background

Serotype-specific urinary antigen detection (UAD) assay results can be used to estimate the serotype contribution among adults with pneumococcal community-acquired pneumonia (CAP) and to guide recommendations regarding higher-valency pneumococcal conjugate vaccines (PCVs).

Methods

Adults aged ≥18 years hospitalized with radiographic evidence of CAP were prospectively enrolled in 4 US cities from November 2019 to December 2020, overlapping the coronavirus disease 2019 (COVID-19) pandemic. Data were collected by patient interview and medical chart review. Streptococcus pneumoniae was isolated from standard-of-care respiratory samples and blood; urine collected per-protocol was tested by S pneumoniae BinaxNOW and UAD assays. The proportions of adults with radiologically confirmed CAP (RAD+ CAP) testing positive for S pneumoniae and for serotypes contained in PCV13, PCV15, and PCV20 were calculated.

Results

Among 3098 adults enrolled, 2105 (67.9%) had RAD+ CAP. Of these, 44.3% were ≥65 years of age, and most had a chronic medical condition (46.0%) or were immunocompromised (38.5%). Streptococcus pneumoniae was detected by any method in 214 (10.2%) RAD+ CAP participants, including 63 (3.0%) with serotypes covered by PCV13, 81 (3.9%) by PCV15, and 119 (5.7%) by PCV20. Streptococcus pneumoniae and PCV serotype positivity were higher before the pandemic (November 2019-April 2020) compared to during the COVID-19 pandemic (May 2020-December 2020).

Conclusions

Our study demonstrated that despite the COVID-19 pandemic, PCV serotype pneumococcus continued to cause an important proportion of adult CAP in the US. These data are useful for informing PCV recommendations and for establishing an epidemiologic baseline to assess the impact of such recommendations.

Vaccinations in older adults: Optimization, strategies, and latest guidelines

This article is a summary of the first AGS Symposium entitled "Update on Vaccination Strategies for Older Adults: Matching the Approach to the Individual and the Care Setting." Given declines in host defenses and immune function with aging, vaccinations play a pivotal role in fortifying older adults against preventable infections, resulting diseases, disability, and death. Current guidelines generally list recommendations applicable for an average older adult of a given chronological age. However, growing evidence indicates that heterogeneity in terms of factors as varied as biological sex, frailty, functional status, and multimorbidity may impact vaccine responses and clinical outcomes. As a result, clinicians will increasingly need to take these additional factors into consideration as they seek to improve outcomes through improved targeting of such aging-related heterogeneity. Moreover, efforts at protecting older citizens through vaccination must also include strategies to overcome barriers to the adoption of vaccine recommendations in varied settings including long-term care. This 2023 AGS Plenary Symposium sought to commence a broader dialogue across AGS and beyond on optimizing vaccinations for older adults, ensuring not only extended lifespans but also healthier and more active lives. This report is not a systematic review, and thus should not be considered comprehensive.

Pneumococcal Septic Arthritis among Adults, France, 2010-2018

Streptococcus pneumoniae infection is considered an uncommon cause of arthritis in adults. To determine the clinical and microbiological characteristics of pneumococcal septic arthritis, we retrospectively studied a large series of cases among adult patients during the 2010-2018 conjugate vaccine era in France. We identified 110 patients (56 women, 54 men; mean age 65 years), and cases included 82 native joint infections and 28 prosthetic joint infections. Most commonly affected were the knee (50/110) and hip (25/110). Concomitant pneumococcal infections were found in 37.2% (38/102) and bacteremia in 57.3% (55/96) of patients, and underlying conditions were noted for 81.4% (83/102). Mortality rate was 9.4% (8/85). The proportion of strains not susceptible to penicillin was 29.1% (32/110). Of the 55 serotyped strains, 31 (56.4%) were covered by standard pneumococcal vaccines; however, several nonvaccine serotypes (mainly 23B, 24F, and 15A) had emerged, for which susceptibility to β-lactams was low.

Klebsiella pneumoniae bioconjugate vaccine functional durability in mice

Klebsiella pneumoniae is a leading cause of hospital-acquired infections as well as the leading cause of neonatal sepsis worldwide. Further, increasing antibiotic resistance in this pathogen makes K. pneumoniae troublesome to treat. Despite its clinical importance, there is not yet an approved K. pneumoniae vaccine available. Here we tested antibody durability and long-term functionality of two previously reported bioconjugate vaccines targeting the K. pneumoniae capsular type K2 and O-antigen type O1v1. We demonstrate that both antibodies are durable in mice for up to six months with significant IgG titers. However, only the K2 antibodies exhibit functionality out to six months as evidenced by serum bactericidal activity and survival in a murine bacteremia challenge model. These results are another promising step towards demonstrating the clinical capacity of bioconjugate vaccines and their induction of durable antibody responses.

Pneumococcal vaccines for prevention of adult pneumonia

Streptococcus pneumoniae, pneumococcus, is one of most important bacterial pathogens in adult community-acquired pneumonia. Although it can cause a variety of illness including invasive diseases (IPD), pneumonia has a greater impact than IPD from the perspective of health economics. 23 valent pneumococcal polysaccharide vaccine (PPSV23) and 13 valent pneumococcal conjugate vaccine (PCV13) have been recommended for people ≥65 years old until recently based on evidence in preventing IPD and pneumonia. Because the introduction and dissemination of PCVs for infants and its effects on herd immunity have led 'serotype replacement' in adult IPD and pneumococcal pneumonia since the 2000s, serotypes targeted by vaccines have sifted accordingly. With the availability of PCV21 this year, in addition to PCV15 and PCV20, vaccine prevention strategies for adult pneumococcal pneumonia need to be reconsidered. In this narrative review, we discuss current and future challenges regarding pneumococcal vaccines to prevent adult pneumococcal pneumonia.

Strategies for pneumococcal vaccination in older adults in the coming era

Pneumonia, predominantly caused by Streptococcus pneumoniae, remains a leading cause of global mortality. The 23-valent Pneumococcal polysaccharide vaccine (PPSV23) and conjugate vaccines (PCVs) are vital measures to fight against it. This paper discussed the changes in pneumococcal vaccination strategies, particularly for older adults, as vaccine effectiveness and epidemiological patterns shift. While PPSV23 maintains effectiveness against invasive pneumococcal disease (IPD), its effectiveness against pneumococcal pneumonia is declining. Conversely, PCV13 consistently demonstrates effectiveness against both IPD and pneumonia. Consequently, the US Centers for Disease Control and Prevention's Advisory Committee on Immunization Practices recommends using PCVs, notably PCV20 and PCV15, over PPSV23. Japanese studies indicate a change in the efficacy/effectiveness of PPSV23 following PCV introduction in children, likely owing to serotype replacement and herd immunity. Additionally, recent data reveals a plateau in the reduction of PCV13 and PPSV23-covered serotypes, posing a challenge to current strategies. This paper indicates a paradigm shift in pneumonia management, acknowledging its chronic nature and potential to exacerbate other diseases. The future of pneumococcal vaccination lies in broader serotype coverage through PCVs, adapting to serotype changes driven by childhood vaccination programs. Furthermore, continuous research and vaccine development are crucial in this evolving field.

Intranasal influenza-vectored vaccine expressing pneumococcal surface protein A protects against Influenza and Streptococcus pneumoniae infections

Streptococcus pneumoniae and influenza A virus (IAV) are significant agents of pneumonia cases and severe respiratory infections globally. Secondary bacterial infections, particularly by Streptococcus pneumoniae, are common in IAV-infected individuals, leading to critical outcomes. Despite reducing mortality, pneumococcal vaccines have high production costs and are serotype specific. The emergence of new circulating serotypes has led to the search for new prevention strategies that provide a broad spectrum of protection. In this context, vaccination using antigens present in all serotypes, such as Pneumococcal Surface Protein A (PspA), can offer broad coverage regardless of serotype. Employing the reverse genetics technique, our research group developed a recombinant influenza A H1N1 virus that expresses PspA (Flu-PspA), through the replacement of neuraminidase by PspA. This virus was evaluated as a bivalent vaccine against infections caused by influenza A and S. pneumoniae in mice. Initially, we evaluated the Flu-PspA virus's ability to infect cells and express PspA in vitro, its capacity to multiply in embryonated chicken eggs, and its safety when inoculated in mice. Subsequently, the protective effect against influenza A and Streptococcus pneumoniae lethal challenge infections in mice was assessed using different immunization protocols. Analysis of the production of antibodies against PspA4 protein and influenza, and the binding capacity of anti-PspA4 antibodies/complement deposition to different strains of S. pneumoniae were also evaluated. Our results demonstrate that the Flu-PspA virus vaccine efficiently induces PspA protein expression in vitro, and that it was able to multiply in embryonated chicken eggs even without exogenous neuraminidase. The Flu-PspA-based bivalent vaccine was demonstrated to be safe, stimulated high titers of anti-PspA and anti-influenza antibodies, and protected mice against homosubtypic and heterosubtypic influenza A and S. pneumoniae challenge. Moreover, an efficient binding of antibodies and complement deposition on the surface of pneumococcal strains ascribes the broad-spectrum vaccine response in vivo. In summary, this innovative approach holds promise for developing a dual-protective vaccine against two major respiratory pathogens.

Clinical and Microbial Determinants of Upper Respiratory Colonization With Streptococcus pneumoniae and Native Microbiota in People With Human Immunodeficiency Virus Type 1 and Control Adults

BACKGROUND

The substantial risk for respiratory and invasive infections with Streptococcus pneumoniae (Spn) among people with HIV-1 (PWH) begins with asymptomatic colonization. The frequency of Spn colonization among US adults with and without HIV-1 infection is not well characterized in the conjugate vaccine era.

METHODS

We determined Spn colonization frequency by culture and specific lytA gene quantitative polymerase chain reaction (PCR) and microbiota profile by 16S ribosomal RNA gene sequencing in nasopharyngeal (NP) and oropharyngeal (OP) DNA from 138 PWH and 93 control adults and associated clinical characteristics.

RESULTS

The frequencies of Spn colonization among PWH and controls did not differ (11.6% vs 8.6%, respectively; P = .46) using combined results of culture and PCR, independent of vaccination or behavioral risks. PWH showed altered microbiota composition (ie, β-diversity; NP: P = .0028, OP: P = .0098), decreased α-diversity (NP: P = .024, OP: P = .0045), and differences in the relative abundance of multiple bacterial taxa. Spn colonization was associated with altered β-diversity in the nasopharynx (P = .011) but not oropharynx (P = .21).

CONCLUSIONS

Despite widespread conjugate vaccine and antiretroviral use, frequencies of Spn colonization among PWH and controls are currently consistent with those reported in the preconjugate era. The persistently increased risk of pneumococcal disease despite antiretroviral therapy may relate to behavioral and immunologic variables other than colonization.

Quantity and Quality of Naturally Acquired Antibody Immunity to the Pneumococcal Proteome Throughout Life

BACKGROUND

Young children and older adults are susceptible for invasive pneumococcal disease (IPD) caused by Streptococcus pneumoniae. Pneumococcal protein-specific antibodies play a protective role against IPD; however, not much is known about the pace of acquisition, maturation, and maintenance of these antibodies throughout life.

METHODS

Immunoglobulin G (IgG) and IgA levels, avidity, and/or specificity to the pneumococcal proteome in serum and saliva from healthy young children, adults, and older adults, with known carriage status, were measured by enzyme-linked immunosorbent assay (ELISA) and 2-dimensional western blotting against ΔcpsTIGR4.

RESULTS

Eleven-month-old children, the youngest age group tested, had the lowest pneumococcal proteome-specific IgG and IgA levels and avidity in serum and saliva, followed by 24-month-old children and were further elevated in adult groups. Among adult groups, the parents had the highest serum and saliva IgG and IgA antibody levels. In children, antibody levels and avidity correlated with daycare attendance and presence of siblings, posing as proxy for exposure and immunization. Immunodominance patterns slightly varied throughout life.

CONCLUSIONS

Humoral immunity against the pneumococcal proteome is acquired through multiple episodes of pneumococcal exposure. Low-level and low-avidity antiproteome antibody profiles in young children may contribute to their IPD susceptibility, while in overall antiproteome antibody-proficient older adults other factors likely play a role.

The Safety and Immunogenicity of a 13-Valent Pneumococcal Polysaccharide Conjugate Vaccine (CRM197/TT) in Infants: A Double-Blind, Randomized, Phase III Trial

OBJECTIVES

This study aimed to evaluate the immunogenicity and safety of a 13-valent pneumococcal polysaccharide conjugate vaccine (CRM197/TT) (PCV13i) in infants.

METHODS

A total of 1200 infants were randomly assigned to either the experimental PCV13i group or the control PCV13 group in a 1:1 ratio. Each group received a three-dose series of the vaccine at 2, 4, and 6 months of age, followed by a booster dose at 12-15 months. Blood samples were collected before and 30 days after both primary and booster vaccinations. The primary immunogenicity endpoints were the seropositive rate and the geometric mean concentration (GMC) of IgG antibodies against the 13 pneumococcal serotypes. The primary safety endpoint was the incidence of adverse reactions within 0-7 days and 0-30 days after vaccination.

RESULTS

Results showed that the experimental PCV13i was well tolerated, with a safety profile comparable to that of the control vaccine. Following primary vaccination, the GMCs of IgG responses against serotypes 1, 5, 6A, 6B, 14, and 18C in the experimental group were lower than those in the control group, while responses against serotypes 3, 4, 7F, 9V, 19A, 19F, and 23F were higher. The experimental group exhibited higher opsonophagocytic killing assay (OPA) geometric mean titers (GMTs) for serotypes 3, 7F, 19A, and 19F compared to the control group, while GMTs for serotypes 1, 5, 6A, and 18C were lower. Following booster vaccination, OPA GMTs of the experimental group remained higher than those of the control group for serotypes 3, 7F, and 19F, while GMTs for serotype 5 were lower. Both vaccines induced robust immune responses, with high seropositive rates and significant increases in antibody levels following vaccination.

CONCLUSIONS

The experimental PCV13i demonstrated non-inferiority to the control PCV13 in terms of immunogenicity.

PNEUMOCOCCAL SEROTYPE DISTRIBUTION AND COVERAGE OF EXISTING AND PIPELINE PNEUMOCOCCAL VACCINES

Background

Streptococcus pneumoniae (pneumococcus) causes invasive pneumococcal disease (IPD) and non-invasive acute respiratory infections (ARIs). Three pneumococcal conjugate vaccines (PCVs) are recommended in the United States with additional products in clinical trials. We aimed to estimate 1) proportions of IPD cases and pneumococcal ARIs caused by serotypes targeted by existing and pipeline PCVs and 2) annual U.S. pneumococcal burdens potentially preventable by PCVs.

Methods

We estimated serotype distribution and proportions of non-invasive pneumococcal ARIs (AOM [children only], sinusitis, non-bacteremic pneumonia) and IPD attributable to serotypes targeted by each PCV using Markov chain Monte Carlo approaches incorporating data from studies of serotype distribution in ARIs and Active Bacterial Core Surveillance (ABCs) data. We then estimated annual numbers of outpatient-managed pneumococcal ARIs, non-bacteremic pneumococcal pneumonia hospitalizations, and IPD cases potentially preventable by PCVs in the United States by multiplying pneumococcal disease incidence rates by PCV-targeted proportions of disease and vaccine effectiveness estimates.

Results

In children, PCV15, PCV20, PCV24, PCV25, and PCV31 serotypes account for 16% (95% confidence interval: 15-17%), 31% (30-32%), 34% (32-35%), 43% (42-44%), and 68% (67-69%) of pneumococcal acute otitis media cases, respectively. In adults, PCV15, PCV20, PCV21, PCV24, PCV25, and PCV31 serotypes account for 43% (38-47%), 52% (47-57%), 69% (64-73%), 65% (61-70%), 62% (57-67%), and 87% (83-90%) of pneumococcal non-bacteremic pneumonia cases. For IPD, 42-85% of pediatric and 42-94% of adult cases were due to PCV-targeted serotypes. PCV-preventable burdens encompassed 270 thousand-3.3 million outpatient-managed ARIs, 2-17 thousand non-bacteremic pneumonia hospitalizations, and 3-14 thousand IPD cases in the United States annually.

Conclusions

Across pneumococcal conditions, coverage and preventable burdens were lowest for PCV15 and highest for PCV31, with PCV21 also targeting sizeable burdens of adult disease. Serotype distribution across syndromes may inform vaccine formulations and policy.

The role of empiric atypical antibiotic coverage in non-severe community-acquired pneumonia

A β-lactam plus a macrolide or a respiratory fluoroquinolone alone is recommended as standard empiric antibacterial therapy for non-severe adults hospitalized with community-acquired pneumonia (CAP) per Infectious Diseases Society of America guidelines. However, the evidence in support of adding empiric atypical antibacterial therapy, and specifically the addition of a macrolide, is conflicting and should be balanced with additional factors: the necessity of covering atypical organisms, benefits of macrolide-associated immunomodulation, harms associated with antibiotic use, and selection for antibiotic-resistant organisms. In this review, we examine the role of atypical coverage in standard treatment regimens for patients admitted with non-severe CAP and specifically focus on the addition of macrolides to β-lactams. We conclude that a subset of patients should not be given atypical coverage as part of their regimen.

Long-term trends and comparison of the burden of lower respiratory tract infections in China and globally from 1990 to 2021: an analysis based on the Global Burden of Disease study 2021

Background

This study aimed to describe the temporal trends in the age and sex burdens of lower respiratory infections (LRIs) in China and globally from 1990 to 2021 and to analyze their epidemiological characteristics to formulate corresponding strategies to control LRIs.

Methods

This study utilized open data from the Global Burden of Disease (GBD) database from 1990 to 2021 to assess the burden of disease based on the prevalence, incidence, mortality, years lost (YLLs), years lived with disability (YLDs), and disability-adjusted life-years (DALYs) of LRIs in China and globally. Moreover, a comprehensive comparative analysis of the epidemiological characteristics of LRIs in China and globally was conducted via the Joinpoint regression model, age-period-cohort model (APC model), and stratified analysis of the study method from multiple dimensions, such as age, sex, and period. Finally, we used an autoregressive integrated moving average (ARIMA) model to predict the disease burden in LRIs over the next 15 years.

Results

From 1990 to 2021, China's age-standardized incidence, deaths, and disability-adjusted life year (DALY) rates per 100,000 people decreased from 5,481.13 (95% CI: 5,149.05, 5,836.35) to 2,853.81 (95% CI: 2,663.94, 3,067.55), from 60.65 (95% CI. 52.96, 66.66) to 14.03 (95% CI: 11.68, 17) and from 3,128.39 (95% CI: 2,724.11, 3,579.57) to 347.67 (95% CI: 301.28, 402.94). The global age-standardized incidence, deaths, and DALY rates per 100,000 people, on the other hand, decreased from 6,373.17 (95% CI: 5,993.51, 6,746.04) to 4,283.61 (95% CI: 4,057.03, 4,524.89) and from 61.81 (95% CI: 56.66, 66.74) to 28.67 (95% CI: 25.92, 31.07) and from 3,472.9 (95% CI: 3,090.71, 3,872.11) to 1,168.8 (95% CI: 1,016.96, 1,336.95). The decline in the aforementioned indicators is greater in the female population than in the male population, and the decrease in China is more pronounced than the global trend. In China, the age-standardized incidence and mortality rates of LRIs showed an annual average percentage change (AAPC) of -2.12 (95% CI: -2.20, -2.03) and -4.77 (95% CI: -5.14, -4.39), respectively. Globally, the age-standardized incidence and mortality rates for LRIs decreased by -1.28 (95% CI: -1.37, -1.18) and -2.47 (95% CI: -2.61, -2.32). By 2036, the incidence of lower respiratory infections (LRI) among men and women in China is projected to decrease by 36.55 and 46.87%, respectively, while the mortality rates are expected to decline to 12.67% for men and increase by 71.85% for women. In comparison, the global decline in LRI incidence is lower than that observed in China, yet the reduction in mortality rates is greater globally than in China.

Conclusions

Age-standardized incidence, mortality and disability-adjusted life years (DALYs) decreased more in China than at the global level between 1990 and 2021. Compared with the previous period, the COVID-19 pandemic has led to a significant decrease in the disease burden of LRIs. As the population continues to age, the disease burden of LRIs in the old adult population will become a major new public health challenge.

National recommendations for adult pneumococcal vaccination in countries of the WHO regions of Americas, Africa, Eastern Mediterranean, South East Asia, and Western Pacific

BACKGROUND

Adults who are elderly or who have underlying health conditions are at particular risk of Streptococcus pneumoniae infections, and pneumococcal vaccines are available. Nonetheless, only national recommendations from countries of North America and Europe have been previously reviewed in the literature.

METHODS

Consequently, we aimed to collate national guidelines for adult pneumococcal immunization across the 161 countries within the World Health Organization (WHO) regions-the Americas (except Canada and the United States of America), Africa, Eastern Mediterranean, South East Asia, and Western Pacific-from country-level official websites and documents, from the WHO portal, and from direct contact with public health officials, pertinent governmental sources, or local vaccination experts.

RESULTS

For 40.4 % (65/161) of these countries, adult pneumococcal vaccination information was available. Among these 65 with available information, 63.1 % (41/65) include adult pneumococcal vaccination in the national vaccination schedule: 58.5 % (24/41) recommend vaccination both for older adults and for risk groups, while 9.8 % (4/41) recommend it only for older adults, and 31.7 % (13/41) only for risk groups. Of note, among the 13 national risk based-only recommendations, 30.8 % (4/13) are age-dependent and strictly reserved for older adults. The regions where age-based adult pneumococcal vaccination recommendations seem to predominate are South East Asia, Western Pacific, and the Americas. The threshold for age-based pneumococcal vaccination recommendations varies between 50 and 70 years of age. The Americas has the highest proportion of countries with risk-based recommendations. Three-quarters of these countries include PCV and PPV23 in the recommendations, most often given in sequence.

CONCLUSIONS

Less than half of countries of the five WHO regions analyzed have accessible information on adult pneumococcal vaccination, and only 25.5 % (41/161) of all countries reviewed recommend adult pneumococcal immunization within the national vaccination schedule. Policymakers should consider extending pneumococcal vaccination guidelines-adapted to national priorities for adult healthcare-as based on local age demographics and risk factor predominance.

Cost-Effectiveness Analysis of the Use of V116, a 21-Valent Pneumococcal Conjugate Vaccine, in Vaccine-Naïve Adults Aged ≥ 65 Years in the United States

INTRODUCTION

Given the recent approval and recommendation of V116, a 21-valent pneumococcal conjugate vaccine (PCV), in the United States (US), we evaluated the cost-effectiveness of using V116 versus the 20-valent PCV (PCV20) or the 15-valent PCV (PCV15) in series with the 23-valent pneumococcal polysaccharide vaccine (PPSV23) among adults aged ≥ 65 years in the US who had never received a PCV previously.

METHODS

A static multi-cohort state-transition Markov model was developed to estimate the lifetime incremental clinical and economic impact of V116 vs. PCV20 or PCV15 + PPSV23 from the societal perspective. All model inputs were based on published literature and publicly available databases and/or reports. Model outcomes included undiscounted clinical cases: invasive pneumococcal disease (IPD), inpatient and outpatient non-bacteremic pneumococcal pneumonia (NBPP), post-meningitis sequelae (PMS), deaths from IPD and inpatient NBPP, discounted quality-adjusted life years (QALYs) as well as the discounted total cost (in 2023 USD), which consisted of vaccine acquisition and administration costs, direct and indirect costs associated with the disease, and travel costs for vaccination. The final summary measure was the incremental cost-effectiveness ratio (ICER), reported as $/QALY gained. Three percent was used for the annual discounting rate.

RESULTS

Based on the inputs and assumptions used, the results indicated that the V116 strategy prevented 27,766 and 32,387 disease cases/deaths and saved $239 million and $1.8 billion in total costs when compared to the PCV20 and PCV15 + PPSV23 strategies, respectively, in vaccine-naïve adults aged ≥ 65 years. The estimated ICERs were cost saving in both regimens (i.e., V116 vs. PCV20 or vs. PCV15 + PPSV23). The scenario analysis and deterministic and probabilistic sensitivity analyses also demonstrated the robustness of the qualitative results.

CONCLUSIONS

These results demonstrated that using V116 in adults aged ≥ 65 years in the US can prevent a substantial number of PD cases and deaths while remaining highly favorable economically over a wide range of inputs and scenarios.

Cost-Effectiveness and Public Health Impact of 24-Valent Pneumococcal Conjugate Vaccine Compared With the Recommended Pneumococcal Vaccines in Older Adults

INTRODUCTION

The potential impact of an in-development 24-valent pneumococcal conjugate vaccine compared with that of currently recommended vaccines in older adults is unclear. Similar to most currently available pneumococcal conjugate vaccines, 24-valent pneumococcal conjugate vaccine's formulation is based on childhood pneumococcal disease epidemiology. Decision analysis techniques were used to estimate 24-valent pneumococcal conjugate vaccine cost-effectiveness and public health effects in U.S. older adults.

METHODS

A Markov model compared 24-valent pneumococcal conjugate vaccine with currently recommended U.S. pneumococcal vaccination strategies in older adults (aged ≥65 years) and with no vaccination. Age-, race-, and chronic medical condition-specific pneumococcal illness risks and serotype-specific disease risks were obtained from Centers for Disease Control and Prevention data. Vaccine effectiveness was estimated using Delphi panel and clinical trial data. Vaccination and pneumococcal illness costs were from U.S.

DATABASES

Scenario analyses examined indirect effects of childhood pneumococcal vaccination on adult disease. Data were collected and analyses were performed in 2024.

RESULTS

The 24-valent pneumococcal conjugate vaccine prevented fewer pneumococcal disease cases and deaths than the recently recommended 21-valent pneumococcal conjugate vaccine, which is formulated on the basis of adult pneumococcal disease serotypes. In cost-effectiveness analyses, 21-valent pneumococcal conjugate vaccine was economically favorable compared with 24-valent pneumococcal conjugate vaccine and all other vaccination strategies, both without and with consideration of potential childhood vaccination indirect effects. These findings were robust and consistent with those in deterministic and probabilistic sensitivity analyses.

CONCLUSIONS

In older adults, 24-valent pneumococcal conjugate vaccine was clinically and economically unfavorable compared with 21-valent pneumococcal conjugate vaccine, which covers more adult disease-causing pneumococcal serotypes and is less susceptible to childhood vaccination indirect effects.

Influenza and pneumococcal vaccination in patients with COPD from 3 French cohorts: Insufficient coverage and associated factors

BACKGROUND

Low vaccination rates against influenza and Streptococcus (S.) pneumoniae infections in COPD could impair outcomes. Understanding underlying factors could help improving implementation.

OBJECTIVES

To describe vaccination rates at inclusion in COPD cohorts and analyze associated factors.

METHODS

Between 2012 and 2018, 5927 patients with sufficient data available were recruited in 3 French COPD cohorts (2566 in COLIBRI-COPD, 2653 in PALOMB and 708 in Initiatives BPCO). Data at inclusion were pooled to describe vaccination rates and analyze associated factors.

RESULTS

Mean age was 66 years, 34 % were women, 35 % were current smokers, mean FEV1 was 58 % predicted, 22 % reported ≥2 exacerbations in the year prior to inclusion, mMRC dyspnea grade was ≥2 in 59 %, 52 % had cardiovascular comorbidities and 9 % a history of asthma. Vaccinations rates in the year prior to study entry were 34.4 % for influenza + S. pneumoniae, 17.5 % for influenza alone and 8.9 % for S. pneumoniae alone. In multivariate analyses, influenza vaccination rate was greater in older age, smoking status, low FEV1, exacerbation history, mMRC dyspnea>2, asthma history, hypertension, diabetes mellitus, and the year of inclusion. SP vaccination was associated with type of practice of the respiratory physician, age, smoking status, FEV1, exacerbation history, dyspnea grade, asthma history and the year of inclusion.

CONCLUSION

Rates of vaccination against influenza and S. pneumoniae infection at inclusion in COPD cohorts remain insufficient and vaccination appears restricted to patients with specific features especially regarding severity and comorbidities, which is not consistent with current recommendations.

Non-invasive Streptococcus pneumoniae infections are associated with different serotypes than invasive infections, Belgium, 2020 to 2023

BackgroundDespite widely implemented pneumococcal vaccination programmes, Streptococcus pneumoniae remains a global risk for human health. Streptococcus pneumoniae can cause invasive (IPD) or non-invasive pneumococcal disease (NIPD). Surveillance is mainly focusing on IPD, assessing the full impact of pneumococcal vaccination programmes on pneumococcal disease is challenging.AimWe aimed to prospectively investigate serotype distribution and antimicrobial resistance (AMR) of S. pneumoniae isolates from patients with NIPD and compare with data on IPD isolates and with a 2007-2008 dataset on NIPD.MethodsBetween September 2020 and April 2023, we collected isolates and patient data from patients with NIPD from 23 clinical laboratories in Belgium. Capsular typing was performed by a validated Fourier-Transform Infrared spectroscopic method, and AMR was assessed with broth microdilution, using the European Committee on Antimicrobial Susceptibility Testing (EUCAST) clinical breakpoints.ResultsWe received S. pneumoniae isolates from 1,008 patients with lower respiratory tract infections (n = 760), otitis media (n = 190) and sinusitis (n = 58). Serotype 3 was the most prevalent serotype among the NIPD isolates. Serotypes not included in the 20-valent pneumococcal conjugate vaccine (PCV20) were significantly more common among the NIPD than among the IPD isolates. Antimicrobial resistance levels were significantly higher among the NIPD isolates (n = 539; 2020-2022) compared with the IPD isolates (n = 2,344; 2021-2022). Resistance to several β-lactam antimicrobials had increased significantly compared with 15 years before.ConclusionsThe NIPD isolates were strongly associated with non-vaccine serotypes and with increased AMR levels. This underlines the importance of continued NIPD surveillance for informed policy making on vaccination programmes.

The incidence of pleural infections in Finland

BACKGROUND

The incidence of pleural infections appears to be increasing in Western countries for unclear reasons. The aim of the study was to describe the incidence and treatment patterns of pleural infections in Finland over three decades.

METHODS

Data regarding each treatment episode for pleural infections in the Finnish special medical care between January 1994 and December 2016 was obtained from a national database and compared to the demographics of Finnish residents obtained from the national census bureau. The annual incidence rates, type of treatment given, as well as the lengths of the hospitalization were analyzed.

RESULTS

A total of 28,463 episodes were reported, of which 55% were inpatient episodes. Of these, 76% concerned males, and the median age of patients was 60 (interquartile range 49-70) years. The overall incidence of pleural infections was 23.4 per 100.000 patient-years, with a male-to-female -ratio of 3.3:1. The annual incidence rates increased throughout the study period with an average annual percentage change of +11.4% (95% CI ±7.4%). The highest incidence rates (>200 per 100.000 patient-years) were observed in men aged 80 or more. Altogether 88% of patients were treated conservatively. The proportion of patients treated by mini-invasive surgery significantly increased during study period (0-5.9%, p < 0.001) and was associated with shorter hospitalization (median 6 [interquartile range 4-12] days) than open surgery (median 7 [4.5-13] days) (p < 0.001).

CONCLUSION

The incidence of pleural infections has increased significantly over the previous decades in Finland and appears to be higher than previously reported, particularly in elderly men.

Supporting vaccine (co)-administration decisions: Development and validation of a tool for assessing the risk of severe outcomes due to lower respiratory tract infections

OBJECTIVE

To develop and validate a score to predict the 90-day risk of hospitalization/death in patients with low respiratory tract infections (LRTIs) with the aim to support clinical decision making on vaccine (co)-administration.

METHODS

We formed a cohort of patients aged 18 years or older being diagnosed with LRTIs in the period between January 1, 2012 and December 31, 2022. Each patient was followed until occurrence of respiratory-related hospitalization/death up to the end of the study period (December 31, 2022). Along with age and sex, forty determinants were adopted to assemble the respiratory tract infection (RTI)-Health Search (HS) core using the development sub-cohort. The prediction accuracy of the score was therefore assessed in the validation sub-cohort.

RESULTS

We identified 252,319 patients being diagnosed with LRTIs (females: 54.7 %; mean age: 60 (SD:18.1)). When the risk of LRTIs-related hospitalizations/deaths was estimated via RTI-HScore, its predicted value was equal to 1.4 % over a 90-day event horizon. The score showed explained variation and discrimination accuracy were equal to 45 % (95 % CI: 44-47 %) and 81 % (95 % CI: 79-84 %), respectively. The calibration slope did not significantly differ from the unit (p = 0.8314).

CONCLUSIONS

The RTI-HScore was featured by good accuracy for prediction of LRTIs-related complications over a 90-day follow-up. Such a tool might therefore support general practitioners to enhance patients' care by facilitating approaches for (co)-administration of vaccines for respiratory infections through a score-based decision support system.

Post-Transplantation Seroprotection Rates in Liver, Lung, and Heart Transplant Recipients Vaccinated Pre-Transplantation against Hepatitis B Virus and Invasive Pneumococcal Disease

Vaccination before solid organ transplantation is recommended since post-transplantation immunosuppression is known to impair vaccine responses. However, little is known about post-transplantation seroprotection rates in organ transplant recipients vaccinated pre-transplantation. We aimed to investigate the proportion of transplant recipients vaccinated against hepatitis B virus (HBV) and invasive pneumococcal disease (IPD) pre-transplantation at the time of listing for transplantation with post-transplantation seroprotection. We included 136 solid organ transplant (SOT) recipients vaccinated at the time of listing for transplantation. We investigated post-transplantation antibody concentrations against HBV and IPD. Established antibody thresholds were used to define seroprotection. The proportions of SOT recipients with post-transplantation seroprotection were 27.9% (n = 38) and 42.6% (n = 58) against HBV and IPD, respectively. Compared to completing HBV vaccination pre-transplantation, completing post-transplantation vaccination (adjusted odds ratio (aOR): 7.8, 95% CI: 2.5-24.5, p < 0.001) and incomplete vaccination (aOR: 6.3, 95% CI: 1.2-32.6, p = 0.028) were associated with non-response against HBV, after adjustment for confounders. Importantly, patients with seroprotection at the time of listing had lower odds of non-response against HBV (aOR: 0.04, 95% CI: 0.0-0.1, p < 0.001) and IPD (aOR: 0.3, 95% CI: 0.1-0.7, p = 0.007) compared to those without seroprotection. SOT recipients vaccinated pre-transplantation had low post-transplantation seroprotection rates against HBV and IPD. However, SOT recipients with seroprotection at the time of listing had lower odds of non-response, suggesting early vaccination should be a priority.

Comparative effectiveness of pneumococcal vaccination strategies to prevent invasive pneumococcal disease: a population-based cohort study at the veterans health administration in the United States

OBJECTIVES

Comparative effectiveness of 13-valent pneumococcal conjugate vaccine (PCV13), 23-valent polysaccharide vaccine (PPSV23), and their combinations for adults in preventing invasive pneumococcal disease (IPD) has yet to be thoroughly investigated. We aimed to estimate the comparative effectiveness of preventing IPD, using population-based data from the Veterans Health Administration (VHA) in the United States.

METHODS

We included all patients who were between 65 and 74 years, had established primary care within VHA between 2005 and 2021, and had not received any prior pneumococcal vaccination. We measured time-to-event from cohort enrolment to the onset of IPD, considering death a competing risk event, and used Cox regression models to estimate cause-specific hazards. PCV13 only, PPSV23 only, PCV13 after PPSV23, and PPSV23 after PCV13 were incorporated into models as time-dependent covariates. Patient demographics and comorbidities were also included in the model.

RESULTS

A total of 3 044 067 patients were enrolled in the cohort, with 863 958 deaths (28.4%) and 1731 cases of IPD (0.06%) during the study period. The overall incidence rate of IPD in this population was 5.36 per 100 000 patient-years. A total of 921 070 patients (30.3%) received at least one dose of effective pneumococcal vaccine. In multivariate analysis adjusted for comorbidities, PCV13 alone was not associated with the reduced risk of IPD, whereas PPSV23 had protective association with IPD incidence (adjusted hazard ratio [aHR], 0.70; 95% CI, 0.59-0.83). When combined, PCV13 followed by PPSV23 had a stronger protective association (aHR, 0.54; [0.36-0.83]) compared with PPSV23 followed by PCV13 (aHR, 0.73; [0.58-0.91]).

DISCUSSION

In this large cohort study at the VHA, the combination of PCV13 and PPSV23, particularly PCV13 followed by PPSV23, was associated with a lower risk of IPD, indicating additional benefits in combined vaccinations with potential importance in vaccination order. Further studies are needed to evaluate the effect of newer pneumococcal vaccines.

The effectiveness of revaccination with pneumococcal polysaccharide vaccine for preventing pneumococcal disease in older adults in England: A population-based cohort study

BACKGROUND

Pneumococcal disease in older adults in the United Kingdom is rising despite immunisation. A key gap in the literature is the clinical effectiveness of revaccination with the pneumococcal polysaccharide vaccine (PPV23).

METHODS

A cohort study was performed in England, using electronic medical records in the Clinical Practice Research Datalink. Individuals aged ≥64 years and vaccinated with PPV23 were included. Rates of hospitalised pneumonia (HP) and invasive pneumococcal disease (IPD) were compared between individuals receiving a single PPV23 dose versus those receiving two doses using multi-level Cox proportional hazards models. Propensity score weighting was performed to minimise the effect of confounding covariates across the comparison groups.

RESULTS

Between 2006 and 2019, there were 462 505 eligible participants. Of those, 6747 (1·5 %) received revaccination. Two doses compared to one dose was associated with an increased risk of HP (adjusted Hazard Ratio [aHR] 1·95; 95 %CI 1·74-2·20) and IPD (aHR 1·44; 95 %CI 1·41-1·46). In participants aged 64-74 years PPV23 revaccination was associated with more IPD (aHR 2·02; 95 %CI 1·75-2·33) and HP (aHR 1·46; 95 %CI 1·42-1.49). In those aged ≥75 years PPV23 revaccination was associated with more HP (aHR 1·12; 95 %CI 1·08-1·16) with no statistically significant difference detected in risk of IPD (aHR 1·20; 95 %CI 0·94-1·52).

CONCLUSIONS

No clear benefit of PPV23 revaccination was measured in older adults in this observational study. The small proportion of revaccinated subjects limits the strength of the conclusions. Further research evaluating the clinical effectiveness of PPV23 revaccination is required.

Global, regional, and national incidence and mortality burden of non-COVID-19 lower respiratory infections and aetiologies, 1990-2021: a systematic analysis from the Global Burden of Disease Study 2021

BACKGROUND

Lower respiratory infections (LRIs) are a major global contributor to morbidity and mortality. In 2020-21, non-pharmaceutical interventions associated with the COVID-19 pandemic reduced not only the transmission of SARS-CoV-2, but also the transmission of other LRI pathogens. Tracking LRI incidence and mortality, as well as the pathogens responsible, can guide health-system responses and funding priorities to reduce future burden. We present estimates from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 of the burden of non-COVID-19 LRIs and corresponding aetiologies from 1990 to 2021, inclusive of pandemic effects on the incidence and mortality of select respiratory viruses, globally, regionally, and for 204 countries and territories.

METHODS

We estimated mortality, incidence, and aetiology attribution for LRI, defined by the GBD as pneumonia or bronchiolitis, not inclusive of COVID-19. We analysed 26 259 site-years of mortality data using the Cause of Death Ensemble model to estimate LRI mortality rates. We analysed all available age-specific and sex-specific data sources, including published literature identified by a systematic review, as well as household surveys, hospital admissions, health insurance claims, and LRI mortality estimates, to generate internally consistent estimates of incidence and prevalence using DisMod-MR 2.1. For aetiology estimation, we analysed multiple causes of death, vital registration, hospital discharge, microbial laboratory, and literature data using a network analysis model to produce the proportion of LRI deaths and episodes attributable to the following pathogens: Acinetobacter baumannii, Chlamydia spp, Enterobacter spp, Escherichia coli, fungi, group B streptococcus, Haemophilus influenzae, influenza viruses, Klebsiella pneumoniae, Legionella spp, Mycoplasma spp, polymicrobial infections, Pseudomonas aeruginosa, respiratory syncytial virus (RSV), Staphylococcus aureus, Streptococcus pneumoniae, and other viruses (ie, the aggregate of all viruses studied except influenza and RSV), as well as a residual category of other bacterial pathogens.

FINDINGS

Globally, in 2021, we estimated 344 million (95% uncertainty interval [UI] 325-364) incident episodes of LRI, or 4350 episodes (4120-4610) per 100 000 population, and 2·18 million deaths (1·98-2·36), or 27·7 deaths (25·1-29·9) per 100 000. 502 000 deaths (406 000-611 000) were in children younger than 5 years, among which 254 000 deaths (197 000-320 000) occurred in countries with a low Socio-demographic Index. Of the 18 modelled pathogen categories in 2021, S pneumoniae was responsible for the highest proportions of LRI episodes and deaths, with an estimated 97·9 million (92·1-104·0) episodes and 505 000 deaths (454 000-555 000) globally. The pathogens responsible for the second and third highest episode counts globally were other viral aetiologies (46·4 million [43·6-49·3] episodes) and Mycoplasma spp (25·3 million [23·5-27·2]), while those responsible for the second and third highest death counts were S aureus (424 000 [380 000-459 000]) and K pneumoniae (176 000 [158 000-194 000]). From 1990 to 2019, the global all-age non-COVID-19 LRI mortality rate declined by 41·7% (35·9-46·9), from 56·5 deaths (51·3-61·9) to 32·9 deaths (29·9-35·4) per 100 000. From 2019 to 2021, during the COVID-19 pandemic and implementation of associated non-pharmaceutical interventions, we estimated a 16·0% (13·1-18·6) decline in the global all-age non-COVID-19 LRI mortality rate, largely accounted for by a 71·8% (63·8-78·9) decline in the number of influenza deaths and a 66·7% (56·6-75·3) decline in the number of RSV deaths.

INTERPRETATION

Substantial progress has been made in reducing LRI mortality, but the burden remains high, especially in low-income and middle-income countries. During the COVID-19 pandemic, with its associated non-pharmaceutical interventions, global incident LRI cases and mortality attributable to influenza and RSV declined substantially. Expanding access to health-care services and vaccines, including S pneumoniae, H influenzae type B, and novel RSV vaccines, along with new low-cost interventions against S aureus, could mitigate the LRI burden and prevent transmission of LRI-causing pathogens.

FUNDING

Bill & Melinda Gates Foundation, Wellcome Trust, and Department of Health and Social Care (UK).

Modelling control strategies for pneumococcal meningitis outbreaks in the African meningitis belt

INTRODUCTION

Pneumococcal meningitis outbreaks occur sporadically in the African meningitis belt. Outbreak control guidelines and interventions are well established for meningococcal but not pneumococcal meningitis. Mathematical modelling is a useful tool for assessing the potential impact of different pneumococcal control strategies. This work aimed to estimate the impact of reactive vaccination with pneumococcal conjugate vaccine (PCV) had it been implemented in past African meningitis belt outbreaks and assess their efficiency relative to existing routine infant immunisation with PCV.

METHODS & RESULTS

Using recent pneumococcal meningitis outbreaks in Burkina Faso, Chad, and Ghana as case studies, we investigated the potential impact of reactive vaccination. We calculated the number needed to vaccinate to avert one case (NNV) in each outbreak setting and over all outbreaks and compared this to the NNV for existing routine infant vaccination. We extended previous analyses of reactive vaccination by considering longer-term protection in vaccinees over five years, incorporating a proxy for indirect effects. We found that implementing reactive vaccination in previous pneumococcal meningitis outbreaks could have averted up to 10-20 % of outbreak cases, with the biggest potential impact in Brong Ahafo, Ghana (2015-2016) and Goundi, Chad (2009). The NNV, and hence the value of reactive vaccination, varied greatly. 'Large' (80 + cumulative modelled cases per 100,000 population) and/or 'prolonged' (exceeding a response threshold of 10 suspected cases per 100,000 per week for four weeks or more) outbreaks had NNV estimates under 10,000. For routine infant vaccination with PCV, the estimated NNV ranged from 3,100-5,600 in Burkina Faso and 1,500-2,600 in Ghana.

IMPLICATIONS

This analysis provides evidence to inform the design of pneumococcal meningitis outbreak response guidelines. Countries should consider reactive vaccination in each outbreak event, together with maintaining routine infant vaccination as the primary intervention to reduce pneumococcal disease burden and outbreak risk.

Surveillance of invasive pneumococcal disease in Spain exploring the impact of the COVID-19 pandemic (2019-2023)

OBJECTIVES

Dynamic trends of invasive pneumococcal disease (IPD) including the evolution of prevalent serotypes are very useful to evaluate the impact of current and future pneumococcal conjugate vaccines (PCVs) and the rise of non-vaccine serotypes. In this study, we include epidemiological patterns of S. pneumoniae before and after COVID-19 pandemic.

METHODS

We characterized all national IPD isolates from children and adults received at the Spanish Pneumococcal Reference Laboratory during 2019-2023.

RESULTS

In the first pandemic year 2020, we found a general reduction in IPD cases across all age groups, followed by a partial resurgence in children in 2021 but not in adults. By 2022, IPD cases in children had returned to pre-pandemic levels, and partially in adults. In 2023, IPD rates surpassed those of the last pre-pandemic year. Notably, the emergence of serotype 3 is of significant concern, becoming the leading cause of IPD in both pediatric and adult populations over the last two years (2022-2023). Increase of serotype 4 in young adults occurred in the last epidemiological years.

CONCLUSIONS

The COVID-19 pandemic led to a temporary decline in all IPD cases during 2020 attributable to non-pharmaceutical interventions followed by a subsequent rise. Employing PCVs with broader coverage and/or enhanced immunogenicity may be critical to mitigate the marked increase of IPD.

Prediction of new-onset atrial fibrillation with the C2HEST score in patients admitted with community-acquired pneumonia

PURPOSE

Patients hospitalized for community-acquired pneumonia (CAP) may have a higher risk of new-onset atrial fibrillation (NOAF). The C2HEST score was developed to evaluate the NOAF risk in the general population. Data on the value of the C2HEST score in acute patients admitted with CAP are lacking. We want to establish the predictive value of C2HEST score for NOAF in patients with CAP.

METHODS

Patients with CAP enrolled in the SIXTUS cohort were enrolled. C2HEST score was calculated at baseline. In-hospital NOAF was recorded. Receiver-operating Characteristic (ROC) curve and multivariable Cox proportional hazard regression analysis were performed.

RESULTS

We enrolled 473 patients (36% women, mean age 70.6 ± 16.5 years), and 54 NOAF occurred. Patients with NOAF were elderly, more frequently affected by hypertension, heart failure, previous stroke/transient ischemic attack, peripheral artery disease and hyperthyroidism. NOAF patients had also higher CURB-65, PSI class and CHA2DS2-VASc score. The C-index of C2HEST score for NOAF was 0.747 (95% confidence interval [95%CI] 0.705-0.786), higher compared to CURB-65 (0.611, 95%CI 0.566-0.655, p = 0.0016), PSI (0.665, 95%CI 0.621-0.708, p = 0.0199) and CHA2DS2-VASc score (0.696, 95%CI 0.652-0.737, p = 0.0762). The best combination of sensitivity (67%) and specificity (70%) was observed with a C2HEST score ≥ 4. This result was confirmed by the multivariable Cox analysis (Hazard Ratio [HR] for C2HEST score ≥ 4 was 10.7, 95%CI 2.0-57.9; p = 0.006), independently from the severity of pneumonia.

CONCLUSION

The C2HEST score was a useful predictive tool to identify patients at higher risk for NOAF during hospitalization for CAP.

CLINICAL TRIAL REGISTRATION

www.

CLINICALTRIALS

gov (NCT01773863).

Molecular and phenotypic characterization of Streptococcus pneumoniae isolates in a Japanese tertiary care hospital

This study aimed to investigate the bacterial characteristics of pneumococcal isolates obtained from a tertiary care hospital in Japan. We analyzed the antimicrobial susceptibility, possession of macrolide resistance genes, pneumococcal serogroup/serotype, and sequence type (ST) of pneumococcal isolates from patients aged 15 years or older between 2011 and 2020 at Nagasaki University Hospital. Of the 73 isolates analyzed, 86.3% showed resistance to macrolides, and 28.8%, 46.6%, and 11.0% harbored mefA, ermB, and both, respectively. Of the isolates possessing ermB, 97.6% showed high levels of macrolide resistance [minimal inhibitory concentration (MIC) range, > 16 µg/mL]. Solithromycin (MIC range, 0.03-0.25 µg/mL), regardless of the presence of macrolide resistance genes, and lascufloxacin (MIC range, 0.06-0.5 µg/mL) showed potent in vitro activity against pneumococci. Serotype 19A was the most prevalent (six isolates), followed by serotypes 10A, 15A, and 15B/C (five isolates each). Four serotypes (11A, 19A, 22F, and 23B) and five STs (36, 99, 433, 558, and 3111) were significantly correlated with the presence of macrolide resistance genes. All four isolates with serotype 11A/ST99 and three isolates with serotype 19A/ST3111 harbored both mefA and ermB. No macrolide resistance genes were detected in either of the two isolates with serotype 22F/ST433, while all ten isolates with serogroup 15 (serotypes 15A and 15B/C, five isolates each) possessed ermB alone. Our study revealed the bacterial characteristics of the pneumococcal isolates obtained from our hospital. In vitro activity of solithromycin and lascufloxacin against these isolates was confirmed.

The impact and cost-effectiveness of pneumococcal immunisation strategies for the elderly in England

Pneumococcal disease, presenting as invasive pneumococcal disease (IPD) or community-acquired pneumonia (CAP) is an important cause of illness and hospitalisation in the elderly. To reduce pneumococcal burden, since 2003, 65-year-olds in England have been offered a 23-valent pneumococcal polysaccharide vaccine (PPV23). This study compares the impact and cost-effectiveness (CE) of vaccination with the existing PPV23 vaccine to the new 15-and 20-valent pneumococcal conjugate vaccines (PCV15 and PCV20), targeting adults aged 65 or 75 years old. We developed a static Markov model for immunisation against pneumococcal disease, capturing different vaccine effectiveness and immunity waning assumptions, projecting the number of IPD/CAP cases averted over the thirty years following vaccination. Using an economic model and probabilistic sensitivity analysis we evaluated the CE of the different immunisation strategies at current vaccine list prices and the willingness-to-pay at a median threshold of £20,000/QALY and an uncertainty threshold of 90% of simulations below £30,000/QALY. PCV20 averted more IPD and CAP cases than PCV15 or PPV23 over the thirty years following vaccination: 353(360), 145(159) and 150(174) IPD and 581(673), 259(485) and 212(235) CAP cases at a vaccination age of 65(75) under base vaccine effectiveness assumptions. At the listed prices of PCV20 and PPV23 vaccines as of May 2023, both vaccines were cost-effective when vaccinating 65- or 75-year-olds with an ICER threshold of £20,000 per QALY. To achieve the same cost-effectiveness as PPV23, the additional cost of PCV20 should be less than £44(£91) at an ICER threshold of £20,000/QALY (£30,000/QALY) if vaccination age is 65 (or £54(£103) if vaccination age is increased to 75). We showed that both PPV23 and PCV20 were likely to be cost-effective. PCV20 was likely to avert more cases of pneumococcal disease in elderly adults in England than the current PPV23 vaccine, given input assumptions of a higher vaccine effectiveness and slower waning for PCV20.

Risk Factors for Cytomegalovirus Retinitis in a National Survey in Sweden

PURPOSE

To investigate predisposing immunosuppressive conditions causing cytomegalovirus retinitis (CMVr) and risk factors for delayed diagnosis in patients diagnosed between 2008 and 2018 in the Swedish population of 10 million.

RESULTS

Sixty-three consecutive patients (100 eyes) were diagnosed with CMVr. The most common immunosuppressive state predisposing for CMVr was hematopoietic stem cell transplant recipients (27%) and hematological malignancy (24%). Two patients (3.2%) had no other predisposing factor than diabetes mellitus (DM). Patients with delayed diagnosis (≤30 days) were older than those with earlier diagnosis, mean age 68.7 (±9.8) and 48.8 (±17.6), respectively, p = .001. Signs of intraocular inflammation (IOI) were seen in 42 (70%) of cases and more common in delayed than early diagnosis, 16 (89%) and 21 (60%) respectively (p = .03).

CONCLUSION

Delayed diagnosis was more common in older individuals with signs of IOI. DM may be a risk factor for CMVr, and clinical signs can be mistaken for diabetic retinopathy.

Protective Effects from Prior Pneumococcal Vaccination in Patients with Chronic Airway Diseases during Hospitalization for Influenza-A Territory-Wide Study

Influenza is an important respiratory viral pathogen in adults, with secondary bacterial pneumonia being a common complication. While pneumococcal vaccines can prevent pneumococcal pneumonia and invasive pneumococcal disease, whether they can also prevent the severe in-hospital outcomes among patients hospitalized for influenza has not been examined. A territory-wide retrospective study was conducted in Hong Kong, which included all adult patients having chronic airway diseases (asthma, bronchiectasis, and chronic obstructive pulmonary disease) hospitalized for influenza and who had received seasonal influenza vaccine. The occurrence of secondary bacterial pneumonia, mortality, and other severe in-hospital outcomes were compared among subjects with or without pneumococcal vaccination. There was a total of 3066 eligible patients who were hospitalized for influenza in public hospitals in Hong Kong from 1 January 2016 to 30 June 2023. Completed pneumococcal vaccination with PSV23/PCV13 conferred protection against secondary bacterial pneumonia, all-cause mortality, and respiratory cause of mortality with adjusted odds ratios of 0.74 (95% CI = 0.57-0.95, p = 0.019), 0.12 (95% CI = 0.03-0.53, p = 0.005), and 0.04 (95% CI = 0.00-0.527, p = 0.0038), respectively.

Outcomes among patients with chronic obstructive pulmonary disease after recovery from COVID-19 infection of different severity

While studies have suggested increased risks of severe COVID-19 infection in chronic obstructive pulmonary disease (COPD), the persistent and delayed consequences of COVID-19 infection on patients with COPD upon recovery remain unknown. A prospective clinical study was conducted in Hong Kong to investigate the persistent and delayed outcomes of patients with COPD who had COVID-19 infection of different severity (mild-moderate COVID-19 and severe COVID-19), compared with those who did not. Chinese patients with COPD ≥ 40 years old were recruited from March to September 2021. They were prospectively followed up for 24.9 ± 5.0 months until 31st August 2023. The primary outcome was the deterioration in COPD control defined as the change in mMRC dyspnea scale. The secondary outcomes included the change in exacerbation frequency and non-COVID-19 respiratory mortality (including death from COPD exacerbation or bacterial pneumonia). 328 patients were included in the analysis. Patients with mild-moderate and severe COVID-19 infection had statistically significant increased risks of worsening of mMRC dyspnoea scale by increase in 1 score from baseline to follow-up with adjusted odds ratios of 4.44 (95% CI = 1.95-10.15, p < 0.001) and 6.77 (95% CI = 2.08-22.00, p = 0.001) respectively. Patients with severe COVID-19 infection had significantly increased risks of increase in severe COPD exacerbation frequency with adjusted odds ratios of 4.73 (95% CI = 1.55-14.41, p = 0.006) non-COVID-19 respiratory mortality from COPD exacerbation or pneumonia with adjusted hazard ratio of 11.25 (95% CI = 2.98-42.45, p < 0.001). After recovery from COVID-19, worsening of COPD control from worsening of dyspnea, increase in severe exacerbation frequency to non-COVID-19 respiratory mortality (COPD exacerbation and pneumonia) was observed among patients with severe COVID-19. Mild to moderate COVID-19 was also associated with symptomatic deterioration.

Medical Causes of Hospitalisation among Patients with Bronchiectasis: A Nationwide Study in Japan

PURPOSE

Although the international guidelines for managing bronchiectasis are centred on preventing the exacerbation of bronchiectasis, the medical causes of admissions to hospital among patients with bronchiectasis have not been fully investigated.

METHODS

This study targeted patients with bronchiectasis who were admitted to hospitals between April 2018 and March 2020 using the national inpatient database in Japan. The causes of hospitalisation and types of antibiotics used for hospitalised patients were recorded.

RESULTS

In total, 21,300 hospitalisations of 16,723 patients with bronchiectasis were analysed. The most common cause was respiratory diseases in 15,145 (71.1%) admissions, including bacterial pneumonia and the exacerbation of bronchiectasis in 6238 (41.2%) and 3151 (20.8%), respectively. Antipseudomonal antibiotics were used in approximately 60% of patients with bacterial pneumonia who were administered antibiotic treatments and in approximately 50% of patients with the exacerbation of bronchiectasis.

CONCLUSIONS

Bacterial pneumonia was the most frequent cause of hospitalisation, followed by the exacerbation of bronchiectasis, among patients with bronchiectasis. Physicians need to focus on the prevention of bacterial pneumonia in addition to the exacerbation of bronchiectasis in patients with bronchiectasis.

Cost-Effectiveness of 20-Valent Pneumococcal Conjugate Vaccine in Argentinean Adults

INTRODUCTION

In Argentina, vaccination with 13-valent pneumococcal conjugate vaccine (PCV13) followed by 23-valent pneumococcal polysaccharide vaccine (PPSV23; PCV13 → PPSV23) has been recommended for all adults aged ≥ 65 years and younger adults with chronic medical ("moderate-risk") or immunocompromising ("high-risk") conditions since 2017. With the approval of a 20-valent PCV (PCV20), we evaluated the cost-effectiveness of PCV20 versus current recommendations for moderate-/high-risk adults aged 18-64 years and all adults 65-99 years.

METHODS

A probabilistic cohort model was used to project lifetime outcomes and costs associated with invasive pneumococcal disease (IPD) and all-cause non-bacteremic pneumonia (NBP), and the expected impact of vaccination. Clinical outcomes were projected annually based on Argentinean data. Economic costs were estimated based on cases and corresponding medical costs (adjusted to 2023 USD) and costs of vaccine and administration. Cost-effectiveness of PCV20 was evaluated versus the current strategy, PCV13 → PPSV23, and alternatively, versus sequentially administered 15-valent PCV and PPSV23 (PCV15 →  PPSV23), and presented as cost per quality-adjusted life year gained; a healthcare system perspective was used. Costs and benefits were discounted at 3%/year.

RESULTS

PCV20 in lieu of PCV13 → PPSV23 among moderate-/high-risk adults aged 18-64 years and all adults 65-99 years (N = 13.4M) prevented 3838 IPD, 4377 inpatient NBP, and 6003 outpatient NBP cases, and 1865 disease-related deaths; relative to PCV15 → PPSV23 the corresponding reductions were 2775, 3285, 4518, and 1348. PCV20 was projected to be the dominant strategy versus PCV13 → PPSV23 and PCV15 → PPSV23 as overall costs were lower by $87.6M and $80.8M, respectively. In probabilistic sensitivity analyses, PCV20 was dominant (i.e., more effective, less costly) in 100% of 1000 simulations.

CONCLUSIONS

Analyses suggest implementing a PCV20 vaccination program in moderate-/high-risk adults aged 18-64 years and all adults ≥ 65 years-in lieu of PCV13 → PPSV23-would yield substantial reductions in pneumococcal disease and would be cost saving to the Argentinean healthcare system.

Invasive Pneumococcal Disease Epidemiology and Serotype Replacement After the Introduction of the 13-Valent Pneumococcal Conjugate Vaccine in Ontario, Canada, 2007-2022

Background

New vaccine products were recently authorized for protection against invasive pneumococcal disease (IPD) in Canada. Our aim was to determine age- and serotype-specific trends in IPD incidence and severity in Canada's largest province, Ontario.

Methods

We included all confirmed IPD cases reported in Ontario and defined the pre-pneumococcal 13-valent conjugate vaccine (PCV13) era (01/2007 to 12/2010), post-PCV13 era (01/2011 to 12/2019), and coronavirus disease 2019 (COVID-19) pandemic era (01/2020 to 12/2022). We estimated incidence, hospitalization, and case fatality rate (CFR) by age. We grouped IPD cases by vaccine-specific serotypes (PCV13; PCV15-non-PCV13; PCV20-non-PCV13; PCV20-non-PCV15; polysaccharide 23-valent vaccine-non-PCV20; and non-vaccine-preventable [NVP]). We then compared incidence rates by age and serotype group in the pre- and post-PCV13 eras by calculating rate ratios (RRs) and their 95% CIs.

Results

Incidence and hospitalizations declined from the pre- to post-PCV13 era in children aged <5 years (RR, 0.7; 95% CI, 0.6-0.8; and RR, 0.8; 95% CI, 0.7-0.9, respectively), but the CFR increased (1.4% to 2.3%). Other age groups saw smaller declines or more stable incidence rates across the years; hospitalizations increased in adults aged 50-64 years (RR, 1.2; 95% CI, 1.1-1.4) and ≥65 years (RR, 1.1; 95% CI, 1.0-1.1). For all ages, IPD cases and hospitalizations attributable to PCV13 serotypes declined, and those attributable to PCV15-non-PCV13, PCV20-non-PCV13, and NVP serotypes increased. IPD incidence declined during the COVID-19 era.

Conclusions

IPD incidence and hospitalizations due to PCV13 serotypes decreased after PCV13 introduction but increased for other serotypes. Continued surveillance is required to evaluate changes to pneumococcal vaccination programs and ongoing changes to the distribution of IPD-causing serotypes.

Pneumococcal vaccination effectiveness (PCV13 and PPSV23) in individuals with and without reduced kidney function: a test-negative design study

Background

Streptococcus pneumoniae vaccination effectiveness (VE) in individuals with reduced kidney function is unknown. We estimated pneumococcal conjugate vaccine (PCV13), pneumococcal polysaccharide vaccine (PPSV23), and combined PCV13 and PPSV23 effectiveness against pneumococcal disease in individuals with and without reduced estimated glomerular filtration rate (eGFR).

Methods

All eligible individuals (case and controls) were adults (aged ≥18 years) hospitalized within the Geisinger Health System and required to have S. pneumoniae urinary antigen testing (i.e. test-negative design). Vaccination records were obtained from the electronic health record and statewide vaccination registry. After controlling for the probability of receiving a pneumococcal vaccine, we used multivariable logistic regression models to estimate the odds ratios (ORs) of vaccination between those who did and did not meet the S. pneumoniae case definition. VE was calculated as (1 - OR) × 100%.

Results

There were 180 cases and 3889 controls (mean age 69 years, female 48%, white 97%, mean eGFR 71 mL/min/1.73 m2). The adjusted population PCV13 VE was 39% (95% CI 13%-58%), and combination PCV13 and PPSV23 was 39% (95% CI 12%-58%). PPSV23 VE was -3.7% (95% CI -57% to 32%). Stratified by eGFR, adjusted PCV13 VE was consistent in eGFR ≥60 [VE 38% (95% CI 2.9%-61%)] and 30-59 [VE 61% (95% CI 24%-80%)] without significant interaction. VE was not calculable for eGFR <30 due to small sample size.

Conclusion

PCV13 vaccination was associated with reduced risk of S. pneumoniae hospitalization in individuals with a reduced eGFR (30-59 mL/min/1.73 m2).

Pneumococcal Vaccination Strategies in 50-Year-Olds to Decrease Racial Disparities: A US Societal Perspective Cost-Effectiveness Analysis

OBJECTIVES

This study assesses the impact of expanding pneumococcal vaccination to all 50-year-olds to decrease racial disparities by estimating from the societal perspective, the cost-effectiveness of 20-valent pneumococcal conjugate vaccine (PCV20) and 15-valent conjugate vaccine followed by 23-valent polysaccharide vaccine (PCV15/PPSV23) for 50-year-olds.

METHODS

A Markov model compared the cost-effectiveness of PCV20 or PCV15/PPSV23 in all general population 50- and 65-years-olds compared with current US recommendations and with no vaccination in US Black and non-Black cohorts. US data informed model parameters. Pneumococcal disease societal costs were estimated using direct and indirect costs of acute illness and of pneumococcal-related long-term disability and mortality. Hypothetical 50-year-old cohorts were followed over their lifetimes with costs and effectiveness discounted 3% per year. Deterministic and probabilistic sensitivity analyses assessed model uncertainty.

RESULTS

In Black cohorts, PCV20 for all at ages 50 and 65 was the least costly strategy and had greater effectiveness than no vaccination and current recommendation strategies, whereas PCV15/PPSV23 at 50 and 65 cost more than $1 million per quality-adjusted life year (QALY) gained compared with PCV20 at 50 and 65. In non-Black cohorts, PCV20 at 50 and 65 cost $62 083/QALY and PCV15/PPSV23 at 50 and 65 cost more than $1 million/QALY with current recommendations, again being more costly and less effective. In probabilistic sensitivity analyses, PCV20 at 50 and 65 was favored in 85.7% (Black) and 61.8% (non-Black) of model iterations at a $100 000/QALY gained willingness-to-pay threshold.

CONCLUSIONS

When considering the societal costs of pneumococcal disease, PCV20 at ages 50 and 65 years in the general US population is a potentially economically viable strategy, particularly in Black cohorts.

Impact of respiratory viral infections on nasopharyngeal pneumococcal colonization dynamics in children

PURPOSE OF REVIEW

Prevention of acute respiratory illnesses (ARI) in children is a global health priority, as these remain a leading cause of pediatric morbidity and mortality throughout the world. As new products and strategies to prevent respiratory infections caused by important pathogens such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), influenza, respiratory syncytial virus and pneumococcus are advancing, increasing evidence suggests that these and other respiratory viruses and pneumococci may exhibit interactions that are associated with altered colonization and disease dynamics. We aim to review recent data evaluating interactions between respiratory viruses and pneumococci in the upper respiratory tract and their potential impact on pneumococcal colonization patterns and disease outcomes.

RECENT FINDINGS

While interactions between influenza infection and subsequent increased susceptibility and transmissibility of colonizing pneumococci have been widely reported in the literature, emerging evidence suggests that human rhinovirus, SARS-CoV-2, and other viruses may also exhibit interactions with pneumococci and alter pneumococcal colonization patterns. Additionally, colonizing pneumococci may play a role in modifying outcomes associated with respiratory viral infections. Recent evidence suggests that vaccination with pneumococcal conjugate vaccines, and prevention of colonization with pneumococcal serotypes included in these vaccines, may be associated with reducing the risk of subsequent viral infection and the severity of the associated illnesses.

SUMMARY

Understanding the direction and dynamics of viral-pneumococcal interactions may elucidate the potential effects of existing and emerging viral and bacterial vaccines and other preventive strategies on the health impact of these important respiratory pathogens.

Association of respiratory infections and the impact of vaccinations on cardiovascular diseases

Influenza, pneumococcal, severe acute respiratory syndrome coronavirus 2, and respiratory syncytial virus infections are important causes of high morbidity and mortality in the elderly. Beyond the burden of infectious diseases, they are also associated with several non-infectious complications like cardiovascular events. A growing body of evidence in prospective studies and meta-analyses has shown the impact of influenza and pneumococcal vaccines on types of cardiovascular outcomes in the general population. Influenza vaccination showed a potential benefit for primary and secondary prevention of cardiovascular diseases across all ages. A reduced risk of cardiovascular events for individuals aged 65 years and older was associated with pneumococcal vaccination. Despite scientific evidence on the effectiveness, safety, and benefits of the vaccines and recommendations to vaccinate elderly patients and those with risk factors, vaccination rates remain sub-optimal in this population. Doubts about vaccine necessity or efficacy and concerns about possible adverse events in patients and physicians refer to delayed acceptance. Vaccination campaigns targeting increasing professional recommendations and public perceptions should be implemented in the coming years. The aim of this review paper is to summarize the effect of vaccination in the field of cardiovascular disease to achieve a higher vaccination rate in this patient population.

Evaluating the health and economic outcomes of a PCV15 vaccination program for adults aged 65 years-and-above in Switzerland

OBJECTIVE

To assess the health and economic outcomes of a PCV13 or PCV15 age-based (65 years-and-above) vaccination program in Switzerland.

INTERVENTIONS

The three vaccination strategies examined were:Target population: All adults aged 65 years-and-above. Perspective(s): Switzerland health care payer.

TIME HORIZON

35 years. Discount rate: 3.0%. Costing year: 2023 Swiss Francs (CHF).

STUDY DESIGN

A static Markov state-transition model.

DATA SOURCES

Published literature and publicly available databases or reports.

OUTCOME MEASURES

Pneumococcal diseases (PD) i.e., invasive pneumococcal diseases (IPD) and non-bacteremic pneumococcal pneumonia (NBPP); total quality-adjusted life-years (QALYs), total costs and incremental cost-effectiveness ratios (CHF/QALY gained).

RESULTS

Using an assumed coverage of 60%, the PCV15 strategy prevented a substantially higher number of cases/deaths than the PCV13 strategy when compared to the No vaccination strategy (1,078 IPD; 21,155 NBPP; 493 deaths). The overall total QALYs were 10,364,620 (PCV15), 10,364,070 (PCV13), and 10,362,490 (no vaccination). The associated overall total costs were CHF 741,949,814 (PCV15), CHF 756,051,954 (PCV13) and CHF 698,329,579 (no vaccination). Thus, the PCV13 strategy was strongly dominated by the PCV15 strategy. The ICER of the PCV15 strategy (vs. no vaccination) was CHF 20,479/QALY gained. In two scenario analyses where the vaccine effectiveness for serotype 3 were reduced (75% to 39.3% for IPD; 45% to 23.6% for NBPP) and NBPP incidence was increased (from 1,346 to 1,636/100,000), the resulting ICERs were CHF 29,432 and CHF 13,700/QALY gained, respectively. The deterministic and probabilistic sensitivity analyses demonstrated the robustness of the qualitative results-the estimated ICERs for the PCV15 strategy (vs. No vaccination) were all below CHF 30,000/QALYs gained.

CONCLUSIONS

These results demonstrate that using PCV15 among adults aged 65 years-and-above can prevent a substantial number of PD cases and deaths while remaining cost-effective over a range of inputs and scenarios.

The prostaglandin D2 antagonist asapiprant ameliorates clinical severity in young hosts infected with invasive Streptococcus pneumoniae

Streptococcus pneumoniae (pneumococcus) remains a serious cause of pulmonary and systemic infections globally, and host-directed therapies are lacking. The aim of this study was to test the therapeutic efficacy of asapiprant, an inhibitor of prostaglandin D2 signaling, against pneumococcal infection. Treatment of young mice with asapiprant after pulmonary infection with invasive pneumococci significantly reduced systemic spread, disease severity, and host death. Protection was specific against bacterial dissemination from the lung to the blood but had no effect on pulmonary bacterial burden. Asapiprant-treated mice had enhanced antimicrobial activity in circulating neutrophils, elevated levels of reactive oxygen species (ROS) in lung macrophages/monocytes, and improved pulmonary barrier integrity indicated by significantly reduced diffusion of fluorescein isothiocyanate (FITC)-dextran from lungs into the circulation. These findings suggest that asapiprant protects the host against pneumococcal dissemination by enhancing the antimicrobial activity of immune cells and maintaining epithelial/endothelial barrier integrity in the lungs.