Immunogenicity and seroefficacy of pneumococcal conjugate vaccines: a systematic review and network meta-analysis.

Background: Vaccination of infants with pneumococcal conjugate vaccines is recommended by the World Health Organization. Evidence is mixed regarding the differences in immunogenicity and efficacy of the different pneumococcal vaccines. Objectives: The primary objective was to compare the immunogenicity of pneumococcal conjugate vaccine-10 versus pneumococcal conjugate vaccine-13. The main secondary objective was to compare the seroefficacy of pneumococcal conjugate vaccine-10 versus pneumococcal conjugate vaccine-13. Methods: We searched the Cochrane Library, EMBASE, Global Health, MEDLINE, ClinicalTrials.gov and trialsearch.who.int up to July 2022. Studies were eligible if they directly compared either pneumococcal conjugate vaccine-7, pneumococcal conjugate vaccine-10 or pneumococcal conjugate vaccine-13 in randomised trials of children under 2 years of age, and provided immunogenicity data for at least one time point. Individual participant data were requested and aggregate data used otherwise. Outcomes included the geometric mean ratio of serotype-specific immunoglobulin G and the relative risk of seroinfection. Seroinfection was defined for each individual as a rise in antibody between the post-primary vaccination series time point and the booster dose, evidence of presumed subclinical infection. Each trial was analysed to obtain the log of the ratio of geometric means and its standard error. The relative risk of seroinfection ('seroefficacy') was estimated by comparing the proportion of participants with seroinfection between vaccine groups. The log-geometric mean ratios, log-relative risks and their standard errors constituted the input data for evidence synthesis. For serotypes contained in all three vaccines, evidence could be synthesised using a network meta-analysis. For other serotypes, meta-analysis was used. Results from seroefficacy analyses were incorporated into a mathematical model of pneumococcal transmission dynamics to compare the differential impact of pneumococcal conjugate vaccine-10 and pneumococcal conjugate vaccine-13 introduction on invasive pneumococcal disease cases. The model estimated the impact of vaccine introduction over a 25-year time period and an economic evaluation was conducted. Results: In total, 47 studies were eligible from 38 countries. Twenty-eight and 12 studies with data available were included in immunogenicity and seroefficacy analyses, respectively. Geometric mean ratios comparing pneumococcal conjugate vaccine-13 versus pneumococcal conjugate vaccine-10 favoured pneumococcal conjugate vaccine-13 for serotypes 4, 9V and 23F at 1 month after primary vaccination series, with 1.14- to 1.54-fold significantly higher immunoglobulin G responses with pneumococcal conjugate vaccine-13. Risk of seroinfection prior to the time of booster dose was lower for pneumococcal conjugate vaccine-13 for serotype 4, 6B, 9V, 18C and 23F than for pneumococcal conjugate vaccine-10. Significant heterogeneity and inconsistency were present for most serotypes and for both outcomes. Twofold higher antibody after primary vaccination was associated with a 54% decrease in risk of seroinfection (relative risk 0.46, 95% confidence interval 0.23 to 0.96). In modelled scenarios, pneumococcal conjugate vaccine-13 or pneumococcal conjugate vaccine-10 introduction in 2006 resulted in a reduction in cases that was less rapid for pneumococcal conjugate vaccine-10 than for pneumococcal conjugate vaccine-13. The pneumococcal conjugate vaccine-13 programme was predicted to avoid an additional 2808 (95% confidence interval 2690 to 2925) cases of invasive pneumococcal disease compared with pneumococcal conjugate vaccine-10 introduction between 2006 and 2030. Limitations: Analyses used data from infant vaccine studies with blood samples taken prior to a booster dose. The impact of extrapolating pre-booster efficacy to post-booster time points is unknown. Network meta-analysis models contained significant heterogeneity which may lead to bias. Conclusions: Serotype-specific differences were found in immunogenicity and seroefficacy between pneumococcal conjugate vaccine-13 and pneumococcal conjugate vaccine-10. Higher antibody response after vaccination was associated with a lower risk of subsequent infection. These methods can be used to compare the pneumococcal conjugate vaccines and optimise vaccination strategies. For future work, seroefficacy estimates can be determined for other pneumococcal vaccines, which could contribute to licensing or policy decisions for new pneumococcal vaccines. Study registration: This study is registered as PROSPERO CRD42019124580. Funding: This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 17/148/03) and is published in full in Health Technology Assessment; Vol. 28, No. 34. See the NIHR Funding and Awards website for further award information.

Pneumococcal disease is a serious illness caused by a bacterial infection that can result in death. Children in the United Kingdom receive a vaccine to prevent this disease that protects against 13 different types of pneumococcal diseases. It is very effective, but other vaccines are also available, such as one that contains 10 types of pneumococcal diseases. Vaccines in the United Kingdom are bought by the government and the choice of which vaccine to provide is based on the cost of the vaccine as well as the benefits to our health. However, there is very little information comparing different vaccines and it is often assumed they are the same. We did a large analysis combining all studies of the two main licensed pneumococcal vaccines to determine which vaccine provides better protection against infection and how this affects costs. We used information from studies published in medical journals, and also data from studies done by the companies that own the vaccines. Our results showed that pneumococcal conjugate vaccine-13 vaccine provided better protection than pneumococcal conjugate vaccine-10 for 5 of the 10 serotypes that are contained in both vaccines. When we used these results to model what might have happened had either of these vaccines been introduced into the United Kingdom vaccination programme in 2006, we found that both vaccines caused a rapid decrease in the amount of disease, but that the decrease in disease was faster with pneumococcal conjugate vaccine-13 than pneumococcal conjugate vaccine-10. This resulted in 2808 cases of diseases prevented over a 25-year time frame with pneumococcal conjugate vaccine-13 compared with pneumococcal conjugate vaccine-10. Our methods can be used to compare other vaccines and we recommend this type of study be done in future when making decisions on vaccine product choice.

Geographical migration and fitness dynamics of Streptococcus pneumoniae.

Streptococcus pneumoniae is a leading cause of pneumonia and meningitis worldwide. Many different serotypes co-circulate endemically in any one location1,2. The extent and mechanisms of spread and vaccine-driven changes in fitness and antimicrobial resistance remain largely unquantified. Here using geolocated genome sequences from South Africa (n = 6,910, collected from 2000 to 2014), we developed models to reconstruct spread, pairing detailed human mobility data and genomic data. Separately, we estimated the population-level changes in fitness of strains that are included (vaccine type (VT)) and not included (non-vaccine type (NVT)) in pneumococcal conjugate vaccines, first implemented in South Africa in 2009. Differences in strain fitness between those that are and are not resistant to penicillin were also evaluated. We found that pneumococci only become homogenously mixed across South Africa after 50 years of transmission, with the slow spread driven by the focal nature of human mobility. Furthermore, in the years following vaccine implementation, the relative fitness of NVT compared with VT strains increased (relative risk of 1.68; 95% confidence interval of 1.59-1.77), with an increasing proportion of these NVT strains becoming resistant to penicillin. Our findings point to highly entrenched, slow transmission and indicate that initial vaccine-linked decreases in antimicrobial resistance may be transient.

Determinants of pneumococcal vaccination dropout among children aged 12-23 months in Ethiopia: a secondary analysis from the 2019 mini demographic and health survey.

Background: Vaccination is a cost-effective public health program that helps reduce significant morbidity and mortality in children under the age of five. Worldwide, the number of vaccine-preventable causes of child death has significantly decreased since the Expanded Program of Immunization (EPI) was introduced. However, for a variety of reasons, 23 million children did not have adequate access to vaccines in 2020. Therefore, this study aimed to evaluate the determinants of pneumonia conjugate vaccine (PCV) dropout among children aged 12-23 months in Ethiopia. Methods: The study analyzed cross-sectional data obtained from the 2019 mini Ethiopian demographic and health survey. Multilevel binary logistic regression analysis was utilized, and the best fit model was chosen using the Akaike Information Criteria. The study comprised a weighted sample of 989 children aged 12 to 23 months. The study presented the Adjusted Odds Ratio (AOR) along with a 95% Confidence Interval (CI) to identify the significant factors influencing PCV dropout. Results: The PCV dropout rate was reported at 20.2% in this study. In the multilevel analysis, possession of a health card (AOR = 0.076, 95% CI: 0.019, 0.04), vaccination for PCV 2 (AOR =0.002, 95% CI: 0.023, 0.263), and region 7 (AOR = 6.98, 95% CI: 10.1, 48.31) were significantly associated with children's PCV dropout. Conclusion: Having a health card, having received the PCV 2 vaccinations, and region were significant predictors of PCV dropout. Consequently, health education on immunization for all mothers and region-specific, customized public health interventions are needed to reduce the vaccination dropout rate.

Knowledge, Attitudes, and Behaviors Regarding Pneumococcal Vaccines in Adults 65 Years and Older in Primary Care in Wisconsin.

INTRODUCTION: Although shared decision-making is highly valued, its implementation in clinical practice is suboptimal. Shared decision-making was included in the Centers for Disease Control and Prevention (CDC) recommendations for the pneumococcal conjugate vaccine 13 valent for older adults. As a first step to develop and test clinician educational resources to facilitate shared decision-making for pneumococcal vaccines for older adults, we completed a needs assessment to identify knowledge gaps, attitudes, and behaviors. METHODS: Primary care clinicians, pharmacists, and patient care staff completed a questionnaire on shared decision-making and pneumococcal vaccines. After the CDC recommended new pneumococcal vaccines and eliminated the role of shared decision-making, a revised questionnaire was distributed to additional clinicians in an effort to increase the sample size. RESULTS: Knowledge of pneumococcal vaccine recommendations was high among those who responded to knowledge questions (48 of 75 respondents). Although 96% of respondents believed shared decision-making for use of pneumococcal vaccines in adults 65 years or older was feasible, 25% responded that it would be "somewhat difficult" to explain potential harms and benefits of PCV13. DISCUSSION: Although shared decision-making was reported to be feasible, challenges implementing it are ongoing. Knowledge gaps regarding pneumococcal vaccines were observed, highlighting the need for ongoing medical education with changing vaccine recommendations.

Serotype distribution, antibiotic resistance, multilocus sequence typing, and virulence factors of invasive and non-invasive Streptococcus pneumoniae in Northeast China from 2000 to 2021.

Streptococcus pneumoniae infection is a major public health concern with high morbidity and mortality rates. This study aimed to evaluate the serotype distribution, antimicrobial resistance changes, clonal composition, and virulence factors of S. pneumoniae isolates causing pneumococcal disease in northeast China from 2000 to 2021. A total of 1,454 S. pneumoniae isolates were included, with 568 invasive strains and 886 non-invasive strains. The patients from whom the S. pneumoniae were isolated ranged in age from 26 days to 95 years, with those ≤ 5 years old comprising the largest group (67.19%). 19 F, 19 A, 23 F, 14, and 6B were the most common serotypes, of which 19 A and 19 F were the main serotypes of invasive and non-invasive S. pneumoniae, respectively. CC271 was the most common multilocus sequence type. Serotype 14 had the lowest expression of cbpA, rrgA, and psrP genes, but expression levels of 19 A and 19 F genes were similar. All isolates were sensitive to ertapenem, moxifloxacin, linezolid, and vancomycin but highly resistant to macrolides, tetracyclines, and cotrimoxazole. Simultaneous resistance to erythromycin, clindamycin, tetracyclines, and trimethoprim/sulfamethoxazole was common pattern among multidrug-resistant isolates. Non-invasive S. pneumoniae had higher resistance to ß-lactam antibiotics than invasive strains. 19 A and 19 F were the main strains of penicillin-resistant S. pneumoniae. The resistance rate of ß-lactam antibiotics decreased from 2017 to 2021 compared to previous periods. Including PCV13 in the national immunization program can reduce the morbidity and mortality rates of pneumococcal disease effectively.

Epithelial cells maintain memory of prior infection with Streptococcus pneumoniae through di-methylation of histone H3.

Epithelial cells are the first point of contact for bacteria entering the respiratory tract. Streptococcus pneumoniae is an obligate human pathobiont of the nasal mucosa, carried asymptomatically but also the cause of severe pneumoniae. The role of the epithelium in maintaining homeostatic interactions or mounting an inflammatory response to invasive S. pneumoniae is currently poorly understood. However, studies have shown that chromatin modifications, at the histone level, induced by bacterial pathogens interfere with the host transcriptional program and promote infection. Here, we uncover a histone modification induced by S. pneumoniae infection maintained for at least 9 days upon clearance of bacteria with antibiotics. Di-methylation of histone H3 on lysine 4 (H3K4me2) is induced in an active manner by bacterial attachment to host cells. We show that infection establishes a unique epigenetic program affecting the transcriptional response of epithelial cells, rendering them more permissive upon secondary infection. Our results establish H3K4me2 as a unique modification induced by infection, distinct from H3K4me3 or me1, which localizes to enhancer regions genome-wide. Therefore, this study reveals evidence that bacterial infection leaves a memory in epithelial cells after bacterial clearance, in an epigenomic mark, thereby altering cellular responses to subsequent infections and promoting infection.

Environmental and genetic regulation of Streptococcus pneumoniae galactose catabolic pathways.

Efficient utilization of nutrients is crucial for microbial survival and virulence. The same nutrient may be utilized by multiple catabolic pathways, indicating that the physical and chemical environments for induction as well as their functional roles may differ. Here, we study the tagatose and Leloir pathways for galactose catabolism of the human pathogen Streptococcus pneumoniae. We show that galactose utilization potentiates pneumococcal virulence, the induction of galactose catabolic pathways is influenced differentially by the concentration of galactose and temperature, and sialic acid downregulates galactose catabolism. Furthermore, the genetic regulation and in vivo induction of each pathway differ, and both galactose catabolic pathways can be turned off with a galactose analogue in a substrate-specific manner, indicating that galactose catabolic pathways can be potential drug targets.

Invasive pneumococcal disease in Latin America and the Caribbean: Serotype distribution, disease burden, and impact of vaccination. A systematic review and meta-analysis.

BACKGROUND: Invasive pneumococcal diseases (IPD) are associated with high morbidity, mortality, and health costs worldwide, particularly in Latin America and the Caribbean (LAC). Surveillance about the distribution of serotypes causing IPD and the impact of pneumococcal vaccination is an important epidemiological tool to monitor disease activity trends, inform public health decision-making, and implement relevant prevention and control measures. OBJECTIVES: To estimate the serotype distribution for IPD and the related disease burden in LAC before, during, and after implementing the pneumococcal vaccine immunization program in LAC. METHODS: Systematic literature review following Cochrane methods of studies from LAC. We evaluated the impact of the pneumococcal vaccine on hospitalization and death during or after hospitalizations due to pneumococcal disease and serotype-specific disease over time. We also analyzed the incidence of serotyped IPD in pneumococcal conjugate vaccine PCV10 and PCV13. The protocol was registered in PROSPERO (ID: CRD42023392097). RESULTS: 155 epidemiological studies were screened and provided epidemiological data on IPD. Meta-analysis of invasive diseases in children <5 years old found that 57%-65% of causative serotypes were included in PCV10 and 66%-84% in PCV13. After PCV introduction, vaccine serotypes declined in IPD, and the emergence of non-vaccine serotypes varied by country. CONCLUSIONS: Pneumococcal conjugate vaccines significantly reduced IPD and shifted serotype distribution in Latin America and the Caribbean. PCV10/PCV13 covered 57-84% of serotypes in children under 5, with marked decline in PCV serotypes post-vaccination. Continuous surveillance remains crucial for monitoring evolving serotypes and informing public health action.

Human monoclonal antibodies protect against viral-mediated pneumococcal superinfection.

Introduction: Community-acquired pneumonia (CAP) is a global health concern, with 25% of cases attributed to Streptococcus pneumoniae (Spn). Viral infections like influenza A virus (IAV), respiratory syncytial virus (RSV), and human metapneumovirus (hMPV) increase the risk of Spn, leading to severe complications due to compromised host immunity. Methods: We evaluated the efficacy of an anti-PhtD monoclonal antibody (mAb) cocktail therapy (PhtD3 + 7) in improving survival rates in three viral/bacterial coinfection models: IAV/Spn, hMPV/Spn, and RSV/Spn. Results: The PhtD3 + 7 mAb cocktail outperformed antiviral mAbs, resulting in prolonged survival. In the IAV/Spn model, it reduced bacterial titers in blood and lungs by 2-4 logs. In the hMPV/Spn model, PhtD3 + 7 provided greater protection than the hMPV-neutralizing mAb MPV467, significantly reducing bacterial titers. In the RSV/Spn model, PhtD3 + 7 offered slightly better protection than the antiviral mAb D25, uniquely decreasing bacterial titers in blood and lungs. Discussion: Given the threat of antibiotic resistance, our findings highlight the potential of anti-PhtD mAb therapy as an effective option for treating viral and secondary pneumococcal coinfections.

Adult Pneumococcal Vaccination in Ghana: Current Status and Future Recommendations - Expert Opinion.

Vaccination programs have proven successful in the prevention and control of infectious diseases among children on a global scale, but the majority of adult populations remain unvaccinated. immunocompromised adults as well as older adults aged low-income countries as Streptococcus pneumoniae infections are associated with substantial morbidity and mortality among 65 years and above. Despite the introduction of pneumococcal conjugate vaccines (PCVs), the burden of vaccine-type serotypes remains high in there are no clear policies for adult vaccination. As per the Global Burden of Disease 2019 report, about 120,000 individuals aged 70 years and older died as a result of LRTIs) in sub-Saharan Africa. A medical advisory board meeting was conducted in April 2022 to discuss the burden of pneumococcal diseases in adults, the current status of policies and practices of adult vaccination, unmet needs, and challenges in Ghana. This expert opinion paper outlines the pneumococcal epidemiology and burden of disease in Ghana, as well as the rationale for adult pneumococcal vaccination. It also highlights the potential barriers to adult vaccination and offers recommendations to overcome these obstacles and enhance vaccine acceptance in Ghana.

Les programmes de vaccination ont prouvé leur succès dans la prévention et le contrôle des maladies infectieuses chez les enfants à l'échelle mondiale, mais la majorité des populations adultes restent non vaccinées. Les infections à Streptococcus pneumoniae sont associées à une morbidité et une mortalité substantielles chez les adultes immunodéprimés ainsi que chez les personnes âgées de 65 ans et plus. Malgré l'introduction des vaccins conjugués contre le pneumocoque (VCP), la charge des sérotypes vaccinaux reste élevée dans les pays à faible revenu car il n'existe pas de politiques claires en matière de vaccination des adultes. Selon le rapport sur la charge mondiale de morbidité de 2019, environ 120 000 personnes âgées de 70 ans et plus sont décédées des suites d'infections des voies respiratoires inférieures (IVRI) en Afrique subsaharienne. Une réunion du conseil consultatif médical a eu lieu en avril 2022 pour discuter du fardeau des maladies pneumococciques chez les adultes, de l'état actuel des politiques et pratiques de vaccination des adultes, des besoins non satisfaits et des défis au Ghana. Cet article d'opinion d'experts présente l'épidémiologie pneumococcique et le fardeau de la maladie au Ghana, ainsi que les arguments en faveur de la vaccination pneumococcique des adultes. Il met également en lumière les obstacles potentiels à la vaccination des adultes et propose des recommandations pour surmonter ces obstacles et améliorer l'acceptation des vaccins au Ghana. MOTS-CLÉS: Maladie pneumococcique, Fardeau de la maladie, Vaccin conjugué contre le pneumocoque, Vaccination des adultes, Streptococcus pneumoniae, Ghana, Défis de la vaccination, Immunisation des adultes, VCP-13, Pneumonie acquise en communauté.

Clinical characteristics and risk factors for poor outcomes of invasive pneumococcal disease in pediatric patients in China.

BACKGROUND: Invasive pneumococcal disease (IPD) is a significant health concern in children worldwide. In this study, we aimed to analyze the clinical features, antibiotic resistance, and risk variables for poor outcomes in patients with IPD in Hangzhou. METHODS: A retrospective single-centre study was performed using the pediatric intensive care (PIC) database from 2010 to 2018. The clinical characteristics, laboratory data, antimicrobial resistance, and risk factors for in-hospital mortality and sepsis in patients with IPD in intensive care units (ICUs) were analyzed systematically. RESULTS: A total of 178 IPD patients were included in the study. The majority of the IPD children were 2-10 years old. Antimicrobial resistance tests of S. pneumoniae isolates revealed high resistance to erythromycin, tetracycline and compound sulfamethoxazole (SMZ-Co). All the isolates were sensitive to vancomycin, linezolid, moxifloxacin, telithromycin, ofloxacin, and levofloxacin. IPD patients may experience poor outcomes, including death and sepsis. The in-hospital mortality was 3.93%, and 34.27% of patients suffered from sepsis. Temperature (OR 3.80, 95% CI 1.62-8.87; P = 0.0021), Partial Pressure of Oxygen in Arterial Blood (PaO2) (OR 0.99, 95% CI 0.98-1.00; P = 0.0266), and albumin (OR 0.89, 95% CI 0.80-0.99; P = 0.0329) were found to be independent risk factors for sepsis in children with IPD. CONCLUSION: Pediatric IPD deserves attention in China. Appropriate surveillance and antibiotic selection are crucial in managing resistant strains. Early identification of high-risk individuals with risk factors contributes to the development of appropriate treatment strategies.

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.

The latest news in France before distribution of third-generation pneumococcal conjugate vaccines.

INTRODUCTION: In 2023 in France, 15 valent- pneumococcal conjugate vaccines (PCV15) have been recommended as alternatives to PCV13 for children < 2 years. PCV20 has been recommended for at-risk adults but not yet for infants, while PCV21 targets older adults. We endeavored to estimate the potential benefit of new pneumococcal vaccines in preventing invasive pneumococcal infections by comparing serotype extension to PCV13. PATIENTS AND METHODS: The National Reference Centre for Pneumococci distributed S. pneumoniae IPD serotypes from children and adults. RESULTS: In 2022, for children under 24 months, PCV15 and PCV20 ensured 10 % and 36 % more coverage against IPD than PCV13. For adults, PCV15, PCV20, and PCV21 covered up to 3 %, 26 %, and 50 % more IPD cases than PCV13. CONCLUSION: The new generation of pneumococcal vaccines could reduce the burden of invasive pneumococcal infections through serotype extension. Additional studies are needed in parallel to optimize their utilization and improve vaccine coverage in France.

Antibody responses after sequential vaccination with PCV13 and PPSV23 in patients with moderate to severe plaque psoriasis under immunosuppressive therapy.

A crucial step in lowering the risk of invasive pneumococcal illness in high-risk populations, such as individuals with plaque psoriasis, is pneumococcal vaccination. The serologic response to the sequential vaccination with Prevenar 13 (PCV13) and Pneumovax 23 (PPSV23) in psoriasis patients under immunosuppressive therapy is still poorly characterized despite national recommendations suggesting vaccination for immunocompromised patients. In this prospective study, we investigated the serological response in 57 patients under active systemic treatment for moderate to severe plaque psoriasis who underwent sequential vaccination with PCV13 followed by PPSV23. Our analysis focused on global and serotype-specific anti-pneumococcal antibody responses over a 7-month period post-vaccination. Our findings reveal a robust serological response in patients with plaque psoriasis under systemic therapy. When comparing our results with a cohort of kidney transplant recipients who completed a similar sequential vaccination protocol, psoriasis patients showed higher antibody concentrations. In psoriasis patients, the mean levels of all global antibody classes tested (IgG, IgG2, IgA, IgM) increased more than 4-fold (P < 0.0001) and serotype-specific antibodies more than 1.9-fold (P < 0.01). In addition to providing strong evidence of the safety and effectiveness of sequential pneumococcal vaccination in individuals with plaque psoriasis, our work sheds light on the complex interactions that exist between immunosuppressive treatment, vaccination schedule, and antibody responses in various risk groups. IMPORTANCE: To protect against severe courses of infection with Streptococcus pneumoniae, the national guidelines recommend sequential vaccination for these patients. However, there are only studies on the efficacy of a single administration of these vaccines in this particular risk group. The immunological responses to the vaccine were correlated with clinical patient data. In summary, our study shows for the first time that sequential vaccination is immunogenic in patients with moderate to severe plaque psoriasis.

Expansion of pneumococcal serotype 23F and 14 lineages with genotypic changes in capsule polysaccharide locus and virulence gene profiles post introduction of pneumococcal conjugate vaccine in Blantyre, Malawi.

Since the introduction of the 13-valent pneumococcal conjugate vaccine (PCV13) in Malawi in 2011, there has been persistent carriage of vaccine serotype (VT) Streptococcus pneumoniae, despite high vaccine coverage. To determine if there has been a genetic change within the VT capsule polysaccharide (cps) loci since the vaccine's introduction, we compared 1022 whole-genome-sequenced VT isolates from 1998 to 2019. We identified the clonal expansion of a multidrug-resistant, penicillin non-susceptible serotype 23F GPSC14-ST2059 lineage, a serotype 14 GPSC9-ST782 lineage and a novel serotype 14 sequence type GPSC9-ST18728 lineage. Serotype 23F GPSC14-ST2059 had an I253T mutation within the capsule oligosaccharide repeat unit polymerase Wzy protein, which is predicted in silico to alter the protein pocket cavity. Moreover, serotype 23F GPSC14-ST2059 had SNPs in the DNA binding sites for the cps transcriptional repressors CspR and SpxR. Serotype 14 GPSC9-ST782 harbours a non-truncated version of the large repetitive protein (Lrp), containing a Cna protein B-type domain which is also present in proteins associated with infection and colonisation. These emergent lineages also harboured genes associated with antibiotic resistance, and the promotion of colonisation and infection which were absent in other lineages of the same serotype. Together these data suggest that in addition to serotype replacement, modifications of the capsule locus associated with changes in virulence factor expression and antibiotic resistance may promote vaccine escape. In summary, the study highlights that the persistence of vaccine serotype carriage despite high vaccine coverage in Malawi may be partly caused by expansion of VT lineages post-PCV13 rollout.

Estimating geographical spread of Streptococcus pneumoniae within Israel using genomic data.

Understanding how pathogens spread across geographical space is fundamental for control measures such as vaccination. Streptococcus pneumoniae (the pneumococcus) is a respiratory bacterium responsible for a large proportion of infectious disease morbidity and mortality globally. Even in the post-vaccination era, the rates of invasive pneumococcal disease (IPD) remain stable in most countries, including Israel. To understand the geographical spread of the pneumococcus in Israel, we analysed 1174 pneumococcal genomes from patients with IPD across multiple regions. We included the evolutionary distance between pairs of isolates inferred using whole-genome data within a relative risk (RR) ratio framework to capture the geographical structure of S. pneumoniae. While we could not find geographical structure at the overall lineage level, the extra granularity provided by whole-genome sequence data showed that it takes approximately 5 years for invasive pneumococcal isolates to become fully mixed across the country.This article contains data hosted by Microreact.

Evaluating patient immunocompetence through antibody response to pneumococcal polysaccharide vaccine using a newly developed 23 serotype multiplexed assay.

Assessing T-cell independent antibody response to polysaccharide vaccines is crucial for diagnosing humoral immune deficiencies. However, immunocompetence criteria based on S. pneumoniae vaccination remain unclear. We evaluated IgG antibody vaccine response in healthy individuals to establish interpretive criteria. Pre- and 4-week post-vaccination sera were collected from 79 adults. Antibody concentrations to PNEUMOVAX 23 serotypes were measured using a multiplexed platform. Immunocompetence was determined by fold increase in post-vaccination response, percentage of serotypes achieving 4- or 2-fold antibody ratio, and post-vaccination concentration ≥ 1.3 µg/mL. Immunogenicity varied widely across the 23 serotypes (26.6% to 94.9% for ≥4-fold increase, 51.9% to 98.7% for ≥2-fold increase). Immunocompetence based on historic criteria of ≥4-fold increase in antibody ratio to ≥70% of serotypes was low (72.2%), but increased to 98.7% with criteria of at least a 2-fold increase and/or post-vaccination concentration ≥ 1.3 µg/mL. Current criteria for assessing immunocompetence may be overly stringent and require updating.

Hearing loss in Australian First Nations children at 6-monthly assessments from age 12 to 36 months: Secondary outcomes from randomised controlled trials of novel pneumococcal conjugate vaccine schedules.

BACKGROUND: In Australian remote communities, First Nations children with otitis media (OM)-related hearing loss are disproportionately at risk of developmental delay and poor school performance, compared to those with normal hearing. Our objective was to compare OM-related hearing loss in children randomised to one of 2 pneumococcal conjugate vaccine (PCV) formulations. METHODS AND FINDINGS: In 2 sequential parallel, open-label, randomised controlled trials (the PREVIX trials), eligible infants were first allocated 1:1:1 at age 28 to 38 days to standard or mixed PCV schedules, then at age 12 months to PCV13 (13-valent pneumococcal conjugate vaccine, +P) or PHiD-CV10 (10-valent pneumococcal Haemophilus influenzae protein D conjugate vaccine, +S) (1:1). Here, we report prevalence and level of hearing loss outcomes in the +P and +S groups at 6-monthly scheduled assessments from age 12 to 36 months. From March 2013 to September 2018, 261 infants were enrolled and 461 hearing assessments were performed. Prevalence of hearing loss was 78% (25/32) in the +P group and 71% (20/28) in the +S group at baseline, declining to 52% (28/54) in the +P groups and 56% (33/59) in the +S group at age 36 months. At primary endpoint age 18 months, prevalence of moderate (disabling) hearing loss was 21% (9/42) in the +P group and 41% (20/49) in the +S group (difference -19%; (95% confidence interval (CI) [-38, -1], p = 0.07) and prevalence of no hearing loss was 36% (15/42) in the +P group and 16% (8/49) in the +S group (difference 19%; (95% CI [2, 37], p = 0.05). At subsequent time points, prevalence of moderate hearing loss remained lower in the +P group: differences -3%; (95% CI [-23, 18], p = 1.00 at age 24 months), -12%; (95% CI [-30, 6], p = 0.29 at age 30 months), and -9%; (95% CI [-23, 5], p = 0.25 at age 36 months). A major limitation was the small sample size, hence low power to reach statistical significance, thereby reducing confidence in the effect size. CONCLUSIONS: In this study, we observed a high prevalence and persistence of moderate (disabling) hearing loss throughout early childhood. We found a lower prevalence of moderate hearing loss and correspondingly higher prevalence of no hearing loss in the +P group, which may have substantial benefits for high-risk children, their families, and society, but warrant further investigation. TRIAL REGISTRATION: ClinicalTrials.gov NCT01735084 and NCT01174849.

Immunogenicity, Immunological Memory and Monitoring of Disease Activity Following an Anamnestic Immunization With the 13-Valent Pneumococcal Conjugate Vaccine in Children With Idiopathic Nephrotic Syndrome.

Anamnestic 13-valent pneumococcal conjugate vaccine immunization did not affect the relapse risk in pediatric idiopathic nephrotic syndrome. Pneumococcal serotype (PS)-specific antibody titers increased significantly in all groups. Children receiving immunomodulatory treatments (IMTs) displayed significantly lower levels of PS-specific antibodies for 3/8 serotypes tested. PS-specific B-cell counts significantly increased only in healthy controls and patients receiving corticosteroids.