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Vaccines Apr 2024We aimed to assess the prevalence of nasopharyngeal pneumococcal carriage and to determine serotype distribution, antibiotic susceptibility patterns, and evolutionary...
We aimed to assess the prevalence of nasopharyngeal pneumococcal carriage and to determine serotype distribution, antibiotic susceptibility patterns, and evolutionary dynamics of isolates in healthy under-five children. Nasopharyngeal swabs were collected from healthy children over three survey periods between 2020 and 2022. All pneumococcal isolates were serotyped and tested for antimicrobial susceptibility. A total of 309 isolates were collected, with an overall prevalence of nasopharyngeal pneumococcal carriage of 24.4% (CI95%: [22-26.8%]). These isolates were classified into 25 different serotypes. The most common serotypes were 14 (14.9%), 19F (12%), 6B (10.4%), and 23F (7.4%), which are covered by the PCV10 vaccine, as well as 19A (8.4%) and 6A (7.8%), which are covered by the PCV13 vaccine. A significant decrease in the proportion of serotype 19F ( = 0.001) and an increase in serotypes 19A ( = 0.034) and 6A ( = 0.029) were observed between the three survey periods. Multidrug resistance (MDR) was noted for 56.6% of the isolates. A significant association with antimicrobial resistance was observed for the most frequent serotypes, mainly serotype 19A. In conclusion, one-quarter of healthy under-five children in Tunisia carried in their nasopharynx. A dominance of vaccine serotypes significantly associated with antimicrobial resistance was recorded.
PubMed: 38675775
DOI: 10.3390/vaccines12040393 -
Vaccines Mar 2024Vaccines prevent a significant number of deaths annually. However, certain populations do not respond adequately to vaccination due to impaired immune systems.... (Review)
Review
Vaccines prevent a significant number of deaths annually. However, certain populations do not respond adequately to vaccination due to impaired immune systems. Cirrhosis, a condition marked by a profound disruption of immunity, impairs the normal immunization process. Critical vaccines for cirrhotic patients, such as the hepatitis A virus (HAV), hepatitis B virus (HBV), influenza, pneumococcal, and coronavirus disease 19 (COVID-19), often elicit suboptimal responses in these individuals. The humoral response, essential for immunization, is less effective in cirrhosis due to a decline in B memory cells and an increase in plasma blasts, which interfere with the creation of a long-lasting response to antigen vaccination. Additionally, some T cell subtypes exhibit reduced activation in cirrhosis. Nonetheless, the persistence of memory T cell activity, while not preventing infections, may help to attenuate the severity of diseases in these patients. Alongside that, the impairment of innate immunity, particularly in dendritic cells (DCs), prevents the normal priming of adaptive immunity, interrupting the immunization process at its onset. Furthermore, cirrhosis disrupts the gut-liver axis balance, causing dysbiosis, reduced production of short-chain fatty acids (SCFAs), increased intestinal permeability, and bacterial translocation. Undermining the physiological activity of the immune system, these alterations could impact the vaccine response. Enhancing the understanding of the molecular and cellular factors contributing to impaired vaccination responses in cirrhotic patients is crucial for improving vaccine efficacy in this population and developing better prevention strategies.
PubMed: 38675732
DOI: 10.3390/vaccines12040349 -
PLoS Computational Biology Apr 2024Multiplex panel tests identify many individual pathogens at once, using a set of component tests. In some panels the number of components can be large. If the panel is...
Multiplex panel tests identify many individual pathogens at once, using a set of component tests. In some panels the number of components can be large. If the panel is detecting causative pathogens for a single syndrome or disease then we might estimate the burden of that disease by combining the results of the panel, for example determining the prevalence of pneumococcal pneumonia as caused by many individual pneumococcal serotypes. When we are dealing with multiplex test panels with many components, test error in the individual components of a panel, even when present at very low levels, can cause significant overall error. Uncertainty in the sensitivity and specificity of the individual tests, and statistical fluctuations in the numbers of false positives and false negatives, will cause large uncertainty in the combined estimates of disease prevalence. In many cases this can be a source of significant bias. In this paper we develop a mathematical framework to characterise this issue, we determine expressions for the sensitivity and specificity of panel tests. In this we identify a counter-intuitive relationship between panel test sensitivity and disease prevalence that means panel tests become more sensitive as prevalence increases. We present novel statistical methods that adjust for bias and quantify uncertainty in prevalence estimates from panel tests, and use simulations to test these methods. As multiplex testing becomes more commonly used for screening in routine clinical practice, accumulation of test error due to the combination of large numbers of test results needs to be identified and corrected for.
Topics: Humans; Prevalence; Sensitivity and Specificity; Computer Simulation; Computational Biology; Streptococcus pneumoniae; Models, Statistical; Pneumonia, Pneumococcal
PubMed: 38669293
DOI: 10.1371/journal.pcbi.1012062 -
Cureus Mar 2024Objective In this study, we aimed to assess the rates of pneumococcal and seasonal influenza vaccinations among elderly and nonelderly diabetes patients and examine...
Objective In this study, we aimed to assess the rates of pneumococcal and seasonal influenza vaccinations among elderly and nonelderly diabetes patients and examine their perceptions and attitudes toward the coronavirus disease 2019 (COVID-19) vaccine. Methods A single-center study was conducted among patients with diabetes, employing a structured survey encompassing sociodemographic data, vaccination records, and the COVID-19 vaccine perception and attitude scale. Results Among the 280 diabetes patients in our study, the vaccination rates for COVID-19, seasonal influenza, and pneumococcal vaccines were 96.1%, 16.8%, and 17.5%, respectively. A higher cumulative dosage of the COVID-19 vaccine was associated with older age (r = 0.463; p<0.001), increased safety score (r = 0.479; p<0.001), and lower conspiracy theory score (r = -0.336; p<0.001). Participants who had received COVID-19 and influenza vaccines were observed to have significantly higher safety scores related to COVID-19 vaccines (p<0.001; d = 2.381 and p = 0.008; d = 0.525, respectively). Notably, vaccination rates for influenza and pneumococcus were significantly different between nonelderly and elderly patients (8.7% vs. 29.6%; p<0.001 and 13.4% vs. 24.1%; p = 0.022). Elderly patients with diabetes were 3.3 times more likely to receive the influenza vaccine than nonelderly participants [odds ratio (OR) = 3.319; 95% confidence interval (CI) = 1.592 - 6.920; p = 0.001] and had a higher safety score related to COVID-19 vaccines (OR = 1.076; 95% CI = 1.011 - 1.146; p = 0.021). Conclusions Both influenza and pneumococcal vaccination rates were below the desired targets in this study. The vaccination rates among the nonelderly diabetes population suggest that this group may be more likely to neglect to receive vaccination compared to the elderly diabetes population. The association between vaccination rates and post-pandemic safety perceptions highlights the critical need to implement public health strategies specifically designed to address and improve safety-related information dissemination.
PubMed: 38665703
DOI: 10.7759/cureus.56943 -
Mucosal adjuvanticity and mucosal booster effect of colibactin-depleted probiotic membrane vesicles.Human Vaccines & Immunotherapeutics Dec 2024There is a growing interest in development of novel vaccines against respiratory tract infections, due to COVID-19 pandemic. Here, we examined mucosal adjuvanticity and...
There is a growing interest in development of novel vaccines against respiratory tract infections, due to COVID-19 pandemic. Here, we examined mucosal adjuvanticity and the mucosal booster effect of membrane vesicles (MVs) of a novel probiotic derivative lacking both flagella and potentially carcinogenic colibactin (ΔΔ). ΔΔ-derived MVs showed rather strong mucosal adjuvanticity as compared to those of a single flagellar mutant strain (Δ-MVs). In addition, glycoengineered ΔΔ-MVs displaying serotype-14 pneumococcal capsular polysaccharide (CPS14MVs) were well-characterized based on biological and physicochemical parameters. Subcutaneous (SC) and intranasal (IN) booster effects of CPS14MVs on systemic and mucosal immunity were evaluated in mice that have already been subcutaneously prime-immunized with the same MVs. With a two-dose regimen, an IN boost (SC-IN) elicited stronger IgA responses than homologous prime-boost immunization (SC-SC). With a three-dose regimen, serum IgG levels were comparable among all tested regimens. Homologous immunization (SC-SC-SC) elicited the highest IgM responses among all regimens tested, whereas SC-SC-SC failed to elicit IgA responses in blood and saliva. Furthermore, serum IgA and salivary SIgA levels were increased with an increased number of IN doses administrated. Notably, SC-IN-IN induced not only robust IgG response, but also the highest IgA response in both serum and saliva among the groups. The present findings suggest the potential of a heterologous three-dose administration for building both systemic and mucosal immunity, . an SC-IN-IN vaccine regimen could be beneficial. Another important observation was abundant packaging of colibactin in MVs, suggesting increased applicability of ΔΔ-MVs in the context of vaccine safety.
Topics: Animals; Mice; Immunity, Mucosal; Probiotics; Escherichia coli; Immunization, Secondary; Female; Adjuvants, Immunologic; Polyketides; Mice, Inbred BALB C; Immunoglobulin A; Peptides; Administration, Intranasal; Immunoglobulin G; Immunoglobulin M; COVID-19 Vaccines
PubMed: 38658133
DOI: 10.1080/21645515.2024.2337987 -
Canada Communicable Disease Report =... Jan 2024The new 15- and 20-valent pneumococcal conjugate vaccines (PCV15 and PCV20) have been marketed on the basis of immunogenicity criteria, one of them being a non-inferior...
BACKGROUND
The new 15- and 20-valent pneumococcal conjugate vaccines (PCV15 and PCV20) have been marketed on the basis of immunogenicity criteria, one of them being a non-inferior response as compared with the 13-valent vaccine (PCV13). In the past, PCV13 was also authorized on the basis of the same criteria, using the 7-valent vaccine (PCV7) as a reference.
METHODS
Our aim was to compare the immunogenicity of these three vaccines in toddlers. Functional opsonophagocytic activity (OPA) titre ratios measured in the same and different randomized trials were computed to assess the respective immunogenicity of these four products.
RESULTS
Results suggest that both PCV15 and PCV20 are less immunogenic than PCV13 for most common serotypes and that the two new vaccines induce a broadly similar response. The PCV7 vaccine was already slightly more immunogenic than PCV13 meaning that PCV15 and PCV20 compare poorly with PCV7. Results also point towards a reduced immunogenicity of the 2+1 dose schedule compared to the 3+1 dose schedule for PCV13, PCV15 and PCV20.
CONCLUSION
Post-marketing studies will have to be conducted to assess the effectiveness of PCV15 and PCV20 and their real-life benefit over PCV13.
PubMed: 38655244
DOI: 10.14745/ccdr.v50i12a04 -
Vaccine May 2024Vaccination against pneumococci is currently the most effective method of protection against pneumococcal infections. The aim of the study was to analyse changes in...
Effect of the PCV 10 vaccination on community-acquired pneumonia hospitalisations after four years of its introduction into the Polish National Immunisation Programme: Follow-up study.
BACKGROUND
Vaccination against pneumococci is currently the most effective method of protection against pneumococcal infections. The aim of the study was to analyse changes in hospitalisations and in-hospital deaths due to pneumonia before (2009-2016) and after (2017-2020) the introduction of PCV 10 vaccinations in the National Immunisation Programme in Poland.
METHODS
Data on hospitalisations related to community acquired pneumonia (CAP) in the years 2009-2020 were obtained from the Nationwide General Hospital Morbidity Study. Analyses were made in the age groups: <2, 2-3, 4-5, 6-19, 20-59, 60+ years in 2009-2016 and 2017-2020.
RESULTS
Overall, there were 1,503,105 CAP-related hospitalisations in 2009-2020, 0.7% of which were caused by Streptococcus pneumoniae infections. Children <2 years of age were the most frequently hospitalised for CAP per 100,000 population, followed by patients aged 2-3, 4-5 and 60+ years. In the years 2009-2016, the percentage of CAP hospital admissions increased significantly, and after the year 2017, it decreased significantly in each of the age groups (p<0.001). In the years 2009-2016, a significant increase in hospitalisations for Streptococcus pneumoniae infections was observed in the age groups <2, 2-3 and 4-5 years (p<0.05). A significant reduction in hospitalisations was observed in the age groups <2, 20-59 and 60+ in 2017-2020 (p<0.05). In the years 2009-2020, there were 84,367 in-hospital deaths due to CAP, 423 (0.5%) of which due to Streptococcus pneumoniae, with patients mainly aged 60+.
CONCLUSIONS
Implementation of the PCV vaccination programme has effectively decreased the incidence of CAP hospitalisations, including children <2 years of age. The group that is most at risk of death are persons aged 60+. The results of our study can be useful in evaluating the vaccine efficacy and benefits, and they can be an essential part of public health policy. Effective prevention strategies for CAP should be implemented in different age groups.
Topics: Humans; Pneumococcal Vaccines; Community-Acquired Infections; Hospitalization; Child, Preschool; Poland; Middle Aged; Adult; Male; Immunization Programs; Female; Infant; Young Adult; Child; Pneumonia, Pneumococcal; Adolescent; Aged; Vaccination; Follow-Up Studies; Streptococcus pneumoniae; Aged, 80 and over; Pneumococcal Infections
PubMed: 38641493
DOI: 10.1016/j.vaccine.2024.04.019 -
Wellcome Open Research 2023Inference on pneumococcal transmission has mostly relied on longitudinal studies which are costly and resource intensive. Therefore, we conducted a pilot study to test...
Inference on pneumococcal transmission has mostly relied on longitudinal studies which are costly and resource intensive. Therefore, we conducted a pilot study to test the ability to infer who infected whom from cross-sectional pneumococcal sequences using phylogenetic inference. Five suspected transmission pairs, for which there was epidemiological evidence of who infected whom, were selected from a household study. For each pair, full genomes were sequenced from nasopharyngeal swabs collected on the same day. The within-host genetic diversity of the pneumococcal population was used to infer the transmission direction and then cross-validated with the direction suggested by the epidemiological records. The pneumococcal genomes clustered into the five households from which the samples were taken. The proportion of concordantly inferred transmission direction generally increased with increasing minimum genome fragment size and single nucleotide polymorphisms. We observed a larger proportion of unique polymorphic sites in the source bacterial population compared to that of the recipient in four of the five pairs, as expected in the case of a transmission bottleneck. The only pair that did not exhibit this effect was also the pair that had consistent discordant transmission direction compared to the epidemiological records suggesting potential misdirection as a result of false-negative sampling. This pilot provided support for further studies to test if the direction of pneumococcal transmission can be reliably inferred from cross-sectional samples if sequenced with sufficient depth and fragment length.
PubMed: 38638914
DOI: 10.12688/wellcomeopenres.19219.1 -
Vaccine May 2024We explored the role of metabolic hormones and the B-cell repertoire in the association between nutritional status and vaccine responses. (Randomized Controlled Trial)
Randomized Controlled Trial
OBJECTIVES
We explored the role of metabolic hormones and the B-cell repertoire in the association between nutritional status and vaccine responses.
METHODS
In this prospective cohort study, nested within a larger randomized open-label trial, 211 South African children received two doses of measles vaccine and two or three doses of pneumococcal conjugate vaccine (PCV). Metabolic markers (leptin, ghrelin and adiponectin) and distribution of B-cell subsets (n = 106) were assessed at 18 months of age.
RESULTS
Children with a weight-for-height z-score (WHZ) ≤ -1 standard deviation (SD) at booster vaccination had a decreased mean serotype-specific PCV IgG response compared with those with WHZ > -1 and <+1 SD or WHZ ≥ +1 SD at 9 months post-booster (18 months of age). (Naive) pre-germinal center B-cells were associated with pneumococcal antibody decay between one to nine months post-booster. Predictive performance of elastic net models for the combined effect of B-cell subsets, metabolic hormones and nutritional status (in addition to age, sex, and randomization group) on measles and PCV vaccine response had an average area under the receiver operating curve of 0.9 and 0.7, respectively.
CONCLUSIONS
The combined effect of B-cell subsets, metabolic hormones and nutritional status correlated well with the vaccination response for measles and most PCV serotypes.
CLINICALTRIALS
gov registration of parent studies: NCT02943902 and NCT03330171.
Topics: Humans; South Africa; Male; Female; Nutritional Status; Prospective Studies; Infant; Pneumococcal Vaccines; Measles Vaccine; Antibodies, Bacterial; Leptin; B-Lymphocytes; Antibodies, Viral; Immunization, Secondary; Immunoglobulin G; Ghrelin; B-Lymphocyte Subsets; Vaccines, Conjugate; Vaccination
PubMed: 38637212
DOI: 10.1016/j.vaccine.2024.04.034 -
PloS One 2024While the 23-valent pneumococcal polysaccharide vaccine (PPV23) has demonstrated its role in preventing severe pneumococcal disease, its impact on more non-specific...
BACKGROUND
While the 23-valent pneumococcal polysaccharide vaccine (PPV23) has demonstrated its role in preventing severe pneumococcal disease, its impact on more non-specific conditions like acute respiratory tract infection (ARI) and lower respiratory tract infections (LRTI) remains unclear. We aimed to investigate the role of PPV23 in prevention of presentations for ARI and LRTI and related antibiotic prescriptions among older adults in primary care.
METHODS
Using a nationwide general practice dataset, we followed a cohort of regularly attending patients aged ≥65 years from 1 January 2014 until 31 December 2018 for presentations for ARI, LRTI, and related antibiotic prescriptions. Associations between PPV23 receipt and each outcome were assessed using a multiple failures survival model to estimate hazard ratios (HR) adjusted for age, sex, socioeconomic status, and various health measures.
RESULTS
A cohort of 75,264 patients aged ≥65 years (mean 75.4, 56% female) in 2014 was followed. The incidence of presentations for ARI, ARI-related antibiotic prescription, LRTI, and LRTI-related antibiotic prescription was 157.6, 76.0, 49.6, and 24.3 per 1000 person-years, respectively. Recent PPV23 vaccine receipt was associated with a small reduction in ARI presentations (adjusted HR vaccinated vs. unvaccinated 0.96; 95%CI 0.94-0.98; p = 0.002); however, there was no reduction in ARI-related antibiotic prescription, LRTI presentation, nor LRTI-related antibiotic prescription (adjusted HR were 0.99[95%CI 0.96-1.03], 1.04[95%CI 0.99-1.09], 1.07[95%CI 1.00-1.14]).
CONCLUSION
PPV23 vaccination in older adults may result in a small reduction in the incidence of total ARI presentations in primary care. However, the effect is small and residual confounding cannot be excluded.
Topics: Humans; Female; Aged; Male; Anti-Bacterial Agents; Respiratory Tract Infections; Streptococcus pneumoniae; Vaccination; Pneumococcal Vaccines; Primary Health Care; Pneumococcal Infections
PubMed: 38635814
DOI: 10.1371/journal.pone.0299924