Your browser doesn't support javascript.
loading
: 20 | 50 | 100
1 - 20 de 5.612
1.
PLoS One ; 19(6): e0304346, 2024.
Article En | MEDLINE | ID: mdl-38843200

BACKGROUND: The Ukrainian Ministerial Order (UMO) recommends pneumococcal vaccine (PCV) in risk groups but not free-of-charge resulting in coverage <5% (crude estimation). In 2022, the vaccination calendar will include PCV for children <5years. Doctors' pneumococcal knowledge, attitudes and practices (КAP) are paramount to successful roll-out but unexplored. We surveyed doctors aiming to assess their KAP to address gaps and misconceptions and support PCV implementation. METHODS: In March 2021, we selected and surveyed primary care doctors using simple random sampling and structured self-administered online questionnaire. We measured attitudes (importance, effectiveness, safety) and practices using 5-point Likert-type questions. We defined pneumococcal disease (PD) knowledge as low/moderate (<80%) and high (≥80%), PCV and overall knowledge as low (≤50%) and moderate/high (51-100%) and PCV attitudes and practices as negative/neutral (1.0-3.4) and positive (3.5-5.0). We calculated prevalence ratios (PRs) and 95% confidence intervals (95%CI) using Poisson regression. RESULTS: The response rate was 46% (286/628). Females represented 85% (243/285); the median age was 47 (interquartile range: 33-59, N = 281) years. Twenty-six percent (72/277) had high PD knowledge associated with age (>47 years: PR = 0.52, 95%CI: 0.30-0.90) and child-related UMO awareness (PR = 1.78, 95%CI: 1.04-3.08); 65% (182/278) had moderate/high PCV knowledge associated with positive attitudes towards PCV effectiveness (PR = 2.08, 95%CI: 1.20-3.59). Overall knowledge was moderate/high in 69% (188/271); 83% (220/265) had positive PCV attitudes; 52% (135/258) had positive practices associated with female sex (PR = 2.11, 95%CI: 1.09-4.09), positive attitudes (PR = 3.40, 95%CI: 1.23-9.39) and perception of vaccine supply as medium/big barrier (PR = 1.66, 95%CI: 1.02-2.72). CONCLUSION: We observed moderate pneumococcal knowledge, especially in older doctors, positive PCV attitudes and neutral practices. Females and doctors with positive attitudes recommended PCV more. For successful PCV implementation, we recommend proper planning and prior educational activities targeting patients and primary care doctors, especially older males, to improve knowledge, introduce PCV and address concerns while ensuring uninterrupted vaccine supply.


Health Knowledge, Attitudes, Practice , Physicians, Primary Care , Pneumococcal Infections , Pneumococcal Vaccines , Vaccination , Humans , Female , Male , Ukraine/epidemiology , Pneumococcal Infections/prevention & control , Pneumococcal Infections/epidemiology , Pneumococcal Vaccines/administration & dosage , Adult , Physicians, Primary Care/psychology , Vaccination/psychology , Vaccination/statistics & numerical data , Middle Aged , Surveys and Questionnaires , Attitude of Health Personnel
2.
Front Immunol ; 15: 1388721, 2024.
Article En | MEDLINE | ID: mdl-38840926

The disaccharide (ß-D-glucopyranosyluronic acid)-(1→4)-ß-D-glucopyranoside represents a repeating unit of the capsular polysaccharide of Streptococcus pneumoniae serotype 3. A conjugate of the disaccharide with BSA (di-BSA conjugate) adjuvanted with aluminum hydroxide induced - in contrast to the non-adjuvanted conjugate - IgG1 antibody production and protected mice against S. pneumoniae serotype 3 infection after intraperitoneal prime-boost immunization. Adjuvanted and non-adjuvanted conjugates induced production of Th1 (IFNγ, TNFα); Th2 (IL-5, IL-13); Th17 (IL-17A), Th1/Th17 (IL-22), and Th2/Th17 cytokines (IL-21) after immunization. The concentration of cytokines in mice sera was higher in response to the adjuvanted conjugate, with the highest level of IL-17A production after the prime and boost immunizations. In contrast, the non-adjuvanted conjugate elicited only weak production of IL-17A, which gradually decreased after the second immunization. After boost immunization of mice with the adjuvanted di-BSA conjugate, there was a significant increase in the number of CD45+/CD19+ B cells, TCR+ γδ T cell, CD5+ В1 cells, and activated cells with MHC II+ expression in the spleens of the mice. IL-17A, TCR+ γδ T cells, and CD5+ В1 cells play a crucial role in preventing pneumococcal infection, but can also contribute to autoimmune diseases. Immunization with the adjuvanted and non-adjuvanted di-BSA conjugate did not elicit autoantibodies against double-stranded DNA targeting cell nuclei in mice. Thus, the molecular and cellular markers associated with antibody production and protective activity in response to immunization with the di-BSA conjugate adjuvanted with aluminum hydroxide are IL-17A, TCR+ γδ T cells, and CD5+ В1 cells against the background of increasing MHC II+ expression.


Interleukin-17 , Pneumococcal Vaccines , Serum Albumin, Bovine , Streptococcus pneumoniae , Animals , Interleukin-17/immunology , Interleukin-17/metabolism , Streptococcus pneumoniae/immunology , Mice , Serum Albumin, Bovine/immunology , Pneumococcal Vaccines/immunology , Pneumococcal Infections/immunology , Pneumococcal Infections/prevention & control , Disaccharides/immunology , Bacterial Capsules/immunology , Polysaccharides, Bacterial/immunology , Adjuvants, Immunologic/administration & dosage , Female , Antibodies, Bacterial/blood , Antibodies, Bacterial/immunology , Intraepithelial Lymphocytes/immunology , Serogroup , Receptors, Antigen, T-Cell, gamma-delta/immunology , Receptors, Antigen, T-Cell, gamma-delta/metabolism
3.
PLoS Med ; 21(6): e1004375, 2024 Jun.
Article En | MEDLINE | ID: mdl-38829821

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.


Hearing Loss , Otitis Media , Pneumococcal Vaccines , Humans , Infant , Pneumococcal Vaccines/administration & dosage , Pneumococcal Vaccines/therapeutic use , Hearing Loss/epidemiology , Australia/epidemiology , Child, Preschool , Female , Male , Otitis Media/epidemiology , Otitis Media/prevention & control , Prevalence , Vaccines, Conjugate/administration & dosage , Pneumococcal Infections/prevention & control , Pneumococcal Infections/epidemiology , Immunization Schedule
4.
J Infect Dev Ctries ; 18(4): 579-586, 2024 Apr 30.
Article En | MEDLINE | ID: mdl-38728636

INTRODUCTION: Streptococcus pneumoniae cause a significant global health challenge. We aimed to determine nasopharyngeal carriage, serotypes distribution, and antimicrobial profile of pneumococci among the children of Aden. METHODOLOGY: A total of 385 children, aged 2-17 years, were included. Asymptomatic samples were randomly collected from children in selected schools and vaccination centers. Symptomatic samples were obtained from selected pediatric clinics. The nasopharyngeal swabs were tested for pneumococci using culture and real time polymerase chain reaction (RT-PCR). Serotyping was done with a pneumotest-latex kit and antimicrobial susceptibility was tested by disc diffusion and Epsilometer test. RESULTS: The total pneumococcal carriage was 44.4% and 57.1% by culture and RT-PCR, respectively. There was a statistically significant association between carriage rate and living in single room (OR = 7.9; p = 0.00001), sharing a sleeping space (OR = 15.1; p = 0.00001), and low monthly income (OR = 2.02; p = 0.007). The common serotypes were 19, 1, 4, 5, 2, and 23. The proportion of non-pneumococcal conjugate vaccine (non-PCV13) serotypes was 24%. Pneumococci were resistant to penicillin (96.5%), cefepime (15.8%), ceftriaxone (16.4%), and amoxicillin-clavulanate (0%). Erythromycin, azithromycin, and doxycycline had resistance rates of 48%, 31%, and 53.3%, respectively. CONCLUSIONS: A high pneumococcal carriage rate was observed in Yemeni children, particularly in low-income households and shared living conditions. There was significant penicillin resistance at meningitis breakpoint. Furthermore, non-PCV13 serotypes were gradually replacing PCV13 serotypes. The findings underscore the urgent need for enhanced surveillance and stewardship to improve vaccination and antibiotic policies in Yemen.


Carrier State , Nasopharynx , Pneumococcal Infections , Pneumococcal Vaccines , Serogroup , Streptococcus pneumoniae , Vaccines, Conjugate , Humans , Streptococcus pneumoniae/drug effects , Streptococcus pneumoniae/isolation & purification , Streptococcus pneumoniae/classification , Child , Child, Preschool , Cross-Sectional Studies , Yemen/epidemiology , Pneumococcal Infections/epidemiology , Pneumococcal Infections/prevention & control , Pneumococcal Infections/microbiology , Female , Male , Pneumococcal Vaccines/administration & dosage , Adolescent , Carrier State/epidemiology , Carrier State/microbiology , Nasopharynx/microbiology , Vaccines, Conjugate/administration & dosage , Anti-Bacterial Agents/pharmacology , Microbial Sensitivity Tests , Serotyping
5.
Expert Rev Vaccines ; 23(1): 546-560, 2024.
Article En | MEDLINE | ID: mdl-38703180

BACKGROUND: The 23-valent pneumococcal polysaccharide vaccine (PPSV23) is used in the Japanese National Immunization Program for older adults and adults with increased risk for pneumococcal disease, however, disease incidence and associated burden remain high. We evaluated the cost-effectiveness of pneumococcal conjugate vaccines (PCVs) for adults aged 65 years and high-risk adults aged 60-64 years in Japan. RESEARCH DESIGN AND METHODS: Using a Markov model, we evaluated lifetime costs using societal and healthcare payer perspectives and estimated quality-adjusted life-years (QALYs), and number of prevented cases and deaths caused by invasive pneumococcal disease (IPD) and non-IPD. The base case analysis used a societal perspective. RESULTS: In comparison with PPSV23, the 20-valent PCV (PCV20) prevented 127 IPD cases 10,813 non-IPD cases (inpatients: 2,461, outpatients: 8,352) and 226 deaths, and gained more QALYs (+0.0015 per person) with less cost (-JPY22,513 per person). All sensitivity and scenario analyses including a payer perspective analysis indicated that the incremental cost-effectiveness ratios (ICERs) were below the cost-effectiveness threshold value in Japan (JPY5 million/QALY). CONCLUSIONS: PCV20 is both cost saving and more effective than PPSV23 for adults aged 65 years and high-risk adults aged 60-64 years in Japan.


Cost-Benefit Analysis , Pneumococcal Infections , Pneumococcal Vaccines , Quality-Adjusted Life Years , Vaccines, Conjugate , Humans , Pneumococcal Vaccines/economics , Pneumococcal Vaccines/administration & dosage , Japan/epidemiology , Pneumococcal Infections/prevention & control , Pneumococcal Infections/economics , Pneumococcal Infections/epidemiology , Middle Aged , Aged , Vaccines, Conjugate/economics , Vaccines, Conjugate/administration & dosage , Vaccines, Conjugate/immunology , Male , Female , Markov Chains , Cost-Effectiveness Analysis
6.
Epidemiol Mikrobiol Imunol ; 73(1): 30-36, 2024.
Article En | MEDLINE | ID: mdl-38697838

Streptococcus pneumoniae (pneumococcus) is a Gram-positive coccus causing both non-invasive and invasive infectious diseases. Pneumococcal diseases are vaccine preventable. Invasive pneumococcal diseases (IPD) meeting the international case definition are reported nationally and internationally and are subject to surveillance programmes in many countries, including the Czech Republic. An important part of IPD surveillance is the monitoring of causative serotypes and their frequency over time and in relation to ongoing vaccination programmes. In the world and in the Czech Republic, whole genome sequencing (WGS) is increasingly used for pneumococci, which allows for serotyping from sequencing data, precise analysis of their genetic relationships, and the study of genes present in their genome. Whole-genome sequencing enables the generation of reliable and internationally comparable data that can be easily shared. Sequencing data are analysed using bioinformatics tools that require knowledge in the field of natural sciences with an emphasis on genetics and expertise in bioinformatics. This publication presents some options for pneumococcal analysis, i.e., serotyping, multilocus sequence typing (MLST), ribosomal MLST (rMLST), core genome MLST (cgMLST), whole genome MLST (wgMLST), single nucleotide polymorphism (SNP) analysis, assignment to Global Pneumococcal Sequence Cluster (GPSC), and identification of virulence genes and antibiotic resistance genes. The WGS strategies and applications for Europe and WGS implementation in practice are presented. WGS analysis of pneumococci allows for improved IPD surveillance, thanks to molecular serotyping, more detailed typing, generation of internationally comparable data, and improved evaluation of the effectiveness of vaccination programmes.


Pneumococcal Infections , Streptococcus pneumoniae , Whole Genome Sequencing , Streptococcus pneumoniae/genetics , Streptococcus pneumoniae/isolation & purification , Streptococcus pneumoniae/classification , Humans , Pneumococcal Infections/microbiology , Pneumococcal Infections/prevention & control , Czech Republic , Genome, Bacterial , Multilocus Sequence Typing , Serotyping
8.
Hum Vaccin Immunother ; 20(1): 2350093, 2024 Dec 31.
Article En | MEDLINE | ID: mdl-38744302

Colorectal cancer (CRC) long-term survivor is a rapid enlarging group. However, the effectiveness of 23-valent pneumococcal polysaccharide vaccine (PPSV23) on this group is unknown. This nationwide population-based study in Taiwan was designed to examine the effect of PPSV23 on incidence rate ratio (IRR) of pneumonia hospitalization, cumulative incidence, and overall survival rate for these long-term CRC survivors. This cohort study was based on the Taiwan Cancer Registry and Taiwan National Health Insurance Research Database from 2000-2017. After individual exact matching to covariates with 1:1 ratio, there were a total of 1,355 vaccinated and 1,355 unvaccinated survivors. After adjusted by multivariate Poisson regression model, vaccinated group had a non-significantly lower pneumonia hospitalization risk than unvaccinated, with an adjusted IRR of 0.879 (p = .391). Besides, vaccinated group had both lower cumulative incidence rate and higher overall survival time than unvaccinated.


Cancer Survivors , Colorectal Neoplasms , Pneumococcal Vaccines , Humans , Pneumococcal Vaccines/administration & dosage , Pneumococcal Vaccines/immunology , Female , Male , Colorectal Neoplasms/mortality , Aged , Taiwan/epidemiology , Incidence , Cohort Studies , Cancer Survivors/statistics & numerical data , Aged, 80 and over , Hospitalization/statistics & numerical data , Middle Aged , Vaccine Efficacy , Pneumococcal Infections/prevention & control , Pneumococcal Infections/epidemiology , Pneumococcal Infections/mortality , Survival Rate , Vaccination , Registries
9.
Vaccine ; 42(15): 3404-3409, 2024 May 31.
Article En | MEDLINE | ID: mdl-38704255

BACKGROUND: Globally, cardiovascular disease (CVD) is the leading cause of death and illness. Vaccine-preventable infections may increase acute coronary vascular disease events and the risk of complications. Low vaccine coverage has been reported among adults at high risk of complications from vaccine-preventable infections. There is a gap in research evidence around determinants of uptake of vaccines among adults with CVD. This study examined the uptake of influenza, pneumococcal and zoster vaccines and the determinants of uptake of the vaccines among cardiac patients. METHOD: A prospective cross-sectional study was carried out among hospitalised cardiac patients through an interviewer-administered questionnaire. Descriptive statistics were used to investigate self-reported uptake of influenza, pneumococcal and zoster vaccines. Univariate and multivariate analyses of participants' social demographic and clinical characteristics were conducted to identify factors for receiving influenza vaccine. RESULTS: Low vaccination rates among 104 participants were found for influenza (45.2%), pneumococcal (13.5%) and zoster (5.8%) vaccines. The most common reason for not receiving influenza vaccine was concern about side effects. Lack of awareness about the pneumococcal and zoster vaccines was the main reason for the poor uptake of these vaccines. Australia-born participants were more likely to receive influenza vaccine than overseas-born participants. Working-age participants and, interestingly, people living with a current smoker were less likely to receive influenza vaccine. CONCLUSION: Influenza, pneumococcal and zoster vaccine uptake among cardiac patients was low. Encouraging physician recommendations for vaccination for cardiac patients under 65 years of age and addressing vaccination challenges among people from culturally and linguistically diverse backgrounds and pharmacy, workplace, and hospital vaccination may help increase vaccination uptake among cardiac patients.


Cardiovascular Diseases , Herpes Zoster Vaccine , Influenza Vaccines , Influenza, Human , Pneumococcal Vaccines , Vaccination , Humans , Male , Female , Influenza Vaccines/administration & dosage , Influenza Vaccines/immunology , Middle Aged , Cross-Sectional Studies , Pneumococcal Vaccines/administration & dosage , Pneumococcal Vaccines/immunology , Aged , Prospective Studies , Influenza, Human/prevention & control , Cardiovascular Diseases/prevention & control , Herpes Zoster Vaccine/administration & dosage , Herpes Zoster Vaccine/immunology , Vaccination/statistics & numerical data , Adult , Pneumococcal Infections/prevention & control , Surveys and Questionnaires , Vaccination Coverage/statistics & numerical data , Australia/epidemiology , Aged, 80 and over
10.
PLoS One ; 19(5): e0297767, 2024.
Article En | MEDLINE | ID: mdl-38768099

BACKGROUND: Streptococcus pneumoniae is a leading cause of morbidity and mortality globally, causing bacteremic pneumonia, meningitis, sepsis, and other invasive pneumococcal diseases. Evidence supports nasopharyngeal pneumococcal carriage as a reservoir for transmission and precursor of pneumococcal disease. OBJECTIVES: To estimate the pneumococcal nasopharyngeal burden in all age groups in Latin America and the Caribbean (LAC) before, during, and after the introduction of pneumococcal vaccine conjugate (PVC). METHODS: Systematic literature review of international, regional, and country-published and unpublished data, together with reports including data from serotype distribution in nasopharyngeal carriage in children and adults from LAC countries following Cochrane methods. The protocol was registered in PROSPERO database (ID: CRD42023392097). RESULTS: We included 54 studies with data on nasopharyngeal pneumococcal carriage and serotypes from 31,803 patients. In children under five years old, carriage was found in 41% and in adults over 65, it was 26%. During the study period, children under five showed a colonization proportion of 34% with PCV10 serotypes and 45% with PCV13 serotypes. When we analyze the carriage prevalence of PCV serotypes in all age groups between 1995 and 2019, serotypes included in PCV10 and those included in PCV13, both showed a decreasing trend along analysis by lustrum. CONCLUSION: The data presented in this study highlights the need to establish national surveillance programs to monitor pneumococcal nasopharyngeal carriage to monitor serotype prevalence and replacement before and after including new pneumococcal vaccines in the region. In addition, to analyze differences in the prevalence of serotypes between countries, emphasize the importance of approaches to local realities to reduce IPD effectively.


Carrier State , Nasopharynx , Pneumococcal Infections , Pneumococcal Vaccines , Streptococcus pneumoniae , Humans , Streptococcus pneumoniae/isolation & purification , Latin America/epidemiology , Caribbean Region/epidemiology , Nasopharynx/microbiology , Pneumococcal Infections/epidemiology , Pneumococcal Infections/prevention & control , Pneumococcal Infections/microbiology , Carrier State/epidemiology , Carrier State/microbiology , Pneumococcal Vaccines/administration & dosage , Serogroup , Child, Preschool , Adult , Child , Prevalence
11.
PLoS One ; 19(5): e0302400, 2024.
Article En | MEDLINE | ID: mdl-38787847

BACKGROUND: In 2012, Botswana introduced 13-valent pneumococcal conjugate vaccine (PCV-13) to its childhood immunization program in a 3+0 schedule, achieving coverage rates of above 90% by 2014. In other settings, PCV introduction has been followed by an increase in carriage or disease caused by non-vaccine serotypes, including some serotypes with a high prevalence of antibiotic resistance. METHODS: We characterized the serotype epidemiology and antibiotic resistance of pneumococcal isolates cultured from nasopharyngeal samples collected from infants (≤12 months) in southeastern Botswana between 2016 and 2019. Capsular serotyping was performed using the Quellung reaction. E-tests were used to determine minimum inhibitory concentrations for common antibiotics. RESULTS: We cultured 264 pneumococcal isolates from samples collected from 150 infants. At the time of sample collection, 81% of infants had received at least one dose of PCV-13 and 53% had completed the three-dose series. PCV-13 serotypes accounted for 27% of isolates, with the most prevalent vaccine serotypes being 19F (n = 20, 8%), 19A (n = 16, 6%), and 6A (n = 10, 4%). The most frequently identified non-vaccine serotypes were 23B (n = 29, 11%), 21 (n = 12, 5%), and 16F (n = 11, 4%). Only three (1%) pneumococcal isolates were resistant to amoxicillin; however, we observed an increasing prevalence of penicillin resistance using the meningitis breakpoint (2016: 41%, 2019: 71%; Cochran-Armitage test for trend, p = 0.0003) and non-susceptibility to trimethoprim-sulfamethoxazole (2016: 55%, 2019: 79%; p = 0.04). Three (1%) isolates were multi-drug resistant. CONCLUSIONS: PCV-13 serotypes accounted for a substantial proportion of isolates colonizing infants in Botswana during a four-year period starting four years after vaccine introduction. A low prevalence of amoxicillin resistance supports its continued use as the first-line agent for non-meningeal pneumococcal infections. The observed increase in penicillin resistance at the meningitis breakpoint and the low prevalence of resistance to ceftriaxone supports use of third-generation cephalosporins for empirical treatment of suspected bacterial meningitis.


Anti-Bacterial Agents , Microbial Sensitivity Tests , Pneumococcal Infections , Pneumococcal Vaccines , Serogroup , Streptococcus pneumoniae , Humans , Streptococcus pneumoniae/drug effects , Streptococcus pneumoniae/isolation & purification , Streptococcus pneumoniae/classification , Botswana/epidemiology , Infant , Pneumococcal Infections/microbiology , Pneumococcal Infections/epidemiology , Pneumococcal Infections/prevention & control , Pneumococcal Infections/drug therapy , Pneumococcal Vaccines/immunology , Female , Anti-Bacterial Agents/pharmacology , Male , Drug Resistance, Bacterial , Serotyping , Nasopharynx/microbiology , Prevalence
13.
Am J Hematol ; 99(6): 1084-1094, 2024 Jun.
Article En | MEDLINE | ID: mdl-38708915

Early mortality in sickle cell disease (SCD) is attributed to increased infections due to loss of splenic function. Marginal zone B cells are important for initial opsonization of pathogens and can be absent in spleen histopathology in SCD. The frequency of unswitched memory B cells (UMBC), the circulating correlate of marginal zone B cells, reflects the immunologic function of the spleen. We hypothesized that asplenia in SCD is associated with alterations in the peripheral blood lymphocyte population and explored whether UMBC deficiency was associated with a clinical phenotype. We analyzed B cell subsets and clinical history for 238 children with SCD and 63 controls. The median proportion of UMBCs was lower in children with SCD compared with controls (4.7% vs. 6.6%, p < .001). Naïve B cells were higher in SCD compared with controls (80.6 vs. 76.3%, respectively, p = .02). UMBC frequency declined by 3.4% per year increase in age in SCD (95% CI: 2%, 4.7%, p < .001), but not in controls. A majority of children in all cohorts had an IgM concentration in the normal range for age and there were no differences between groups (p = .13). Subjects developed titers adequate for long-term protection to fewer serotypes in the polysaccharide vaccine than controls (14.7 vs. 19.4, p < .001). In this cohort, bacteremia was rare and specific clinical complications were not associated with UMBC proportion. In summary, UMBC deficiency occurs in SCD and is associated with age. Future studies should investigate B cell subsets prospectively and identify the mechanism of B cell loss in the spleen.


Anemia, Sickle Cell , Memory B Cells , Pneumococcal Vaccines , Humans , Anemia, Sickle Cell/immunology , Anemia, Sickle Cell/complications , Pneumococcal Vaccines/immunology , Pneumococcal Vaccines/therapeutic use , Child , Male , Female , Child, Preschool , Memory B Cells/immunology , Adolescent , B-Lymphocyte Subsets/immunology , Pneumococcal Infections/immunology , Pneumococcal Infections/prevention & control , Spleen/immunology , Spleen/pathology , Immunoglobulin M/blood
14.
Emerg Infect Dis ; 30(6): 1164-1172, 2024 Jun.
Article En | MEDLINE | ID: mdl-38781925

As a follow-up to a previous study, we investigated vaccine effectiveness (VE) of 23-valent pneumococcal polysaccharide vaccine (PPSV23) against invasive pneumococcal disease (IPD) among 1,254,498 persons >65 years of age as part of a vaccination program in Denmark during April 2020-January 2023. We assessed VE by using a Cox regression model and adjusted for age, sex, and underlying conditions. Using nationwide data, we estimated a VE of PPSV23 against all-type IPD of 32% and against PPSV23-serotype IPD of 41%. Because this follow-up study had more statistical power than the original study, we also estimated VE against IPD caused by PPSV23-serotypes excluding serotype 3; serotype 3; serotype 8; serotype 22F; PPSV23 non-PCV15 serotypes; PPSV23 non-PCV20 serotypes; and IPD over time. Our findings suggest PPSV23 vaccination can protect persons >65 years of age against IPD caused by all serotypes or serotype groupings, except serotype 3.


Pneumococcal Infections , Pneumococcal Vaccines , Serogroup , Streptococcus pneumoniae , Humans , Pneumococcal Vaccines/immunology , Pneumococcal Vaccines/administration & dosage , Pneumococcal Infections/prevention & control , Pneumococcal Infections/epidemiology , Pneumococcal Infections/microbiology , Pneumococcal Infections/immunology , Denmark/epidemiology , Female , Aged , Male , Streptococcus pneumoniae/immunology , Streptococcus pneumoniae/classification , Follow-Up Studies , Aged, 80 and over , Vaccine Efficacy , Vaccination
15.
Vaccine ; 42(16): 3555-3563, 2024 Jun 11.
Article En | MEDLINE | ID: mdl-38704263

BACKGROUND: A U.S. case-control study (2010-2014) demonstrated vaccine effectiveness (VE) for ≥ 1 dose of the thirteen-valent pneumococcal conjugate vaccine (PCV13) against vaccine-type (VT) invasive pneumococcal disease (IPD) at 86 %; however, it lacked statistical power to examine VE by number of doses and against individual serotypes. METHODS: We used the indirect cohort method to estimate PCV13 VE against VT-IPD among children aged < 5 years in the United States from May 1, 2010 through December 31, 2019 using cases from CDC's Active Bacterial Core surveillance, including cases enrolled in a matched case-control study (2010-2014). Cases and controls were defined as individuals with VT-IPD and non-PCV13-type-IPD (NVT-IPD), respectively. We estimated absolute VE using the adjusted odds ratio of prior PCV13 receipt (1-aOR x 100 %). RESULTS: Among 1,161 IPD cases, 223 (19.2 %) were VT cases and 938 (80.8 %) were NVT controls. Of those, 108 cases (48.4 %; 108/223) and 600 controls (64.0 %; 600/938) had received > 3 PCV13 doses; 23 cases (17.6 %) and 15 controls (2.4 %) had received no PCV doses. VE ≥ 3 PCV13 doses against VT-IPD was 90.2 % (95 % Confidence Interval75.4-96.1 %), respectively. Among the most commonly circulating VT-IPD serotypes, VE of ≥ 3 PCV13 doses was 86.8 % (73.7-93.3 %), 50.2 % (28.4-80.5 %), and 93.8 % (69.8-98.8 %) against serotypes 19A, 3, and 19F, respectively. CONCLUSIONS: At least three doses of PCV13 continue to be effective in preventing VT-IPD among children aged < 5 years in the US. PCV13 was protective against serotypes 19A and 19F IPD; protection against serotype 3 IPD did not reach statistical significance.


Pneumococcal Infections , Pneumococcal Vaccines , Serogroup , Streptococcus pneumoniae , Humans , Pneumococcal Vaccines/administration & dosage , Pneumococcal Vaccines/immunology , Pneumococcal Infections/prevention & control , Pneumococcal Infections/epidemiology , United States/epidemiology , Child, Preschool , Infant , Female , Male , Streptococcus pneumoniae/immunology , Streptococcus pneumoniae/classification , Case-Control Studies , Vaccines, Conjugate/immunology , Vaccines, Conjugate/administration & dosage , Vaccine Efficacy/statistics & numerical data , Cohort Studies , Infant, Newborn , Vaccination/statistics & numerical data
17.
Front Immunol ; 15: 1392316, 2024.
Article En | MEDLINE | ID: mdl-38711516

Streptococcus pneumoniae remains a significant global threat, with existing vaccines having important limitations such as restricted serotype coverage and high manufacturing costs. Pneumococcal lipoproteins are emerging as promising vaccine candidates due to their surface exposure and conservation across various serotypes. While prior studies have explored their potential in mice, data in a human context and insights into the impact of the lipid moiety remain limited. In the present study, we examined the immunogenicity of two pneumococcal lipoproteins, DacB and MetQ, both in lipidated and non-lipidated versions, by stimulation of primary human immune cells. Immune responses were assessed by the expression of common surface markers for activation and maturation as well as cytokines released into the supernatant. Our findings indicate that in the case of MetQ lipidation was crucial for activation of human antigen-presenting cells such as dendritic cells and macrophages, while non-lipidated DacB demonstrated an intrinsic potential to induce an innate immune response. Nevertheless, immune responses to both proteins were enhanced by lipidation. Interestingly, following stimulation of dendritic cells with DacB, LipDacB and LipMetQ, cytokine levels of IL-6 and IL-23 were significantly increased, which are implicated in triggering potentially important Th17 cell responses. Furthermore, LipDacB and LipMetQ were able to induce proliferation of CD4+ T cells indicating their potential to induce an adaptive immune response. These findings contribute valuable insights into the immunogenic properties of pneumococcal lipoproteins, emphasizing their potential role in vaccine development against pneumococcal infections.


Adaptive Immunity , Bacterial Proteins , Cytokines , Streptococcus pneumoniae , Humans , Streptococcus pneumoniae/immunology , Cytokines/metabolism , Bacterial Proteins/immunology , Lipoproteins/immunology , Lipoproteins/metabolism , Dendritic Cells/immunology , Dendritic Cells/metabolism , Antigen-Presenting Cells/immunology , Antigen-Presenting Cells/metabolism , Pneumococcal Vaccines/immunology , Pneumococcal Infections/immunology , Pneumococcal Infections/prevention & control , Macrophages/immunology , Macrophages/metabolism , Cells, Cultured
18.
J Med Econ ; 27(1): 644-652, 2024.
Article En | MEDLINE | ID: mdl-38577742

AIM: The US Food and Drug Administration approved the 20-valent pneumococcal conjugate vaccine (PCV20) to prevent pneumococcal disease. In the context of routine PCV20 vaccination, we evaluated the cost-effectiveness and public health and economic impact of a PCV20 catch-up program and estimated the number of antibiotic prescriptions and antibiotic-resistant infections averted. MATERIALS AND METHODS: A population-based, multi-cohort, decision-analytic Markov model was developed using parameters consistent with previous PCV20 cost-effectiveness analyses. In the intervention arm, children aged 14-59 months who previously completed PCV13 vaccination received a supplemental dose of PCV20. In the comparator arm, no catch-up PCV20 dose was given. The direct and indirect benefits of vaccination were captured over a 10-year time horizon. RESULTS: A PCV20 catch-up program would prevent 5,469 invasive pneumococcal disease cases, 50,286 hospitalized pneumonia cases, 218,240 outpatient pneumonia cases, 582,302 otitis media cases, and 1,800 deaths, representing a net gain of 30,014 life years and 55,583 quality-adjusted life years. Furthermore, 720,938 antibiotic prescriptions and 256,889 antibiotic-resistant infections would be averted. A catch-up program would result in cost savings of $800 million. These results were robust to sensitivity and scenario analyses. CONCLUSIONS: A PCV20 catch-up program could prevent pneumococcal infections, antibiotic prescriptions, and antimicrobial-resistant infections and would be cost-saving in the US.


Pneumococcal Infections , Pneumonia , Child , Humans , Vaccines, Conjugate/therapeutic use , Anti-Bacterial Agents/therapeutic use , Cost-Benefit Analysis , Drug Resistance, Bacterial , Pneumococcal Infections/prevention & control
19.
Vaccine ; 42(12): 3084-3090, 2024 Apr 30.
Article En | MEDLINE | ID: mdl-38584056

BACKGROUND: In 2020 Australia changed the funded universal older adult pneumococcal vaccination program from use of the 23-valent pneumococcal polysaccharide vaccine (PPV23) at age 65 to the 13-valent pneumococcal conjugate vaccine (PCV13) at age 70 years. We investigated uptake of both PCV13 and PPV23 in older adults before and after the program change. METHODS: We analysed a national dataset of records of patients attending general practices (GPs). We included regular attendees aged 65 or above in 2020. Cumulative uptake of PCV13 and monthly uptake of PPV23 was compared for the two periods before (January 2019 to June 2020) and after (July 2020 to May 2021) the program change on 1 July 2020, by age groups and presence of comorbid conditions. RESULTS: Our study included data from 192,508 patients (mean age in 2020: 75.1 years, 54.2 % female, 46.1 % with at least one comorbidity). Before July 2020, for all adults regardless of underlying comorbidities, the cumulative uptake of PCV13 was < 1 % but by May 2021, eleven months after the program changes, cumulative uptake of PCV13 had increased among those aged 70-79 years (without comorbidity: 16.3 %; with comorbidity: 21.1 %) and 80 + years (without comorbidity: 13.5 %; with comorbidity: 17.7 %), but not among those aged 65-69 years (without comorbidity: 1.3 %; with comorbidity: 3 %). Monthly uptake of PPV23 dropped following the program change across all age groups. CONCLUSIONS: Changes in uptake of PCV13 and PPV23 among those aged 70 + years were consistent with program changes. However, PCV13 uptake was still substantially lower in individuals aged 65-69 years overall and in those with comorbidities.


Pneumococcal Infections , Humans , Female , Aged , Male , Pneumococcal Infections/epidemiology , Pneumococcal Infections/prevention & control , Australia/epidemiology , Vaccines, Conjugate , Pneumococcal Vaccines , Streptococcus pneumoniae
20.
Vaccine ; 42(12): 3091-3098, 2024 Apr 30.
Article En | MEDLINE | ID: mdl-38594120

BACKGROUND: The study evaluated the protective effect of 13-valent pneumococcal polysaccharide conjugate vaccine (PCV13) against all-cause hospitalized pneumonia in children in Beijing. METHODS: Based on the vaccination record and inpatient medical record database of Beijing, children born in 2017 in Beijing, matched by age, gender, and district of the children with the ratio of 1:4, were selected as the vaccinated and unvaccinated groups according whether if vaccinated with PCV13. The incidence rate and 95 % confidence interval (95 %CI), vaccine effectiveness (VE) and direct medical costs of all-cause hospitalized pneumonia were calculated and compared within the same period of 12 months, 18 months, 24 months and 30 months after the birth of the child. RESULTS: The decreased incidence rates of all-cause hospitalized pneumonia were observed at the four points in the PCV13 vaccinated group compared to the unvaccinated group, which were significant at the points of 12 months (0.42 % vs. 0.72 %, P = 0.001), 18 months (0.90 % vs. 1.26 %, P = 0.002) and 24 months (1.37 % vs. 1.65 %, P = 0.046). The VE of PCV13 against all-cause hospitalized pneumonia within 12 months was the highest as 41.9 % (95 % CI 19.6 %, 58.0 %), followed by 29.3 % (95 % CI 11.4 %, 43.5 %) within 18 months, 17.1 % (95 % CI 0.3 %, 31.1 %) within 24 months and it almost disappeared within 30 months. The VE of 4-dose vaccination within 18 months and 24 months were 39.9 % (95 % CI 20.3 %, 54.7 %) and 27.2 % (95 % CI 8.6 %, 42.0 %), respectively. The median hospitalization cost of the children in the vaccinated group was higher at the four points but without significance. CONCLUSIONS: PCV13 had a certain protective effect on all-cause hospitalized pneumonia, and the booster immunization strategy had the best protective effect with great public health significance to enter the immunization program.


Pneumococcal Infections , Pneumonia, Pneumococcal , Child , Humans , Infant , Pneumococcal Infections/prevention & control , Streptococcus pneumoniae , Beijing/epidemiology , Pneumonia, Pneumococcal/epidemiology , Pneumonia, Pneumococcal/prevention & control , Pneumococcal Vaccines , Hospitalization , Vaccines, Conjugate
...