Search Results (87)

Background: Characterization of cellular responses to vaccinations in immunocompromised patients remains an evolving area of research. This particularly applies for pneumococcal vaccination in diseases such as psoriasis and in the setting of immunosuppressive therapy. Methods: This prospective study included 42 patients with moderate-to-severe psoriasis. Following German guidelines at the time, patients underwent a sequential vaccination protocol against Streptococcus pneumoniae, consisting of Prevenar 13 (PCV13) and Pneumovax 23 (PPSV23). Over a 7-month period, we analyzed T-cell responses to common serotypes of Streptococcus pneumoniae using an interferon-γ ELISpot assay. For comparison, we performed an ELISA to measure pneumococcus-specific antibody production. Results: Patients undergoing anti-TNF-α blocker therapy, monoclonal antibody therapy (specifically anti-IL-12/23, IL-23, and IL-17), and methotrexate therapy showed significantly different responses to the pneumococcal serotype PS14 at onset (p = 0.02). T-cell responses ranged from strong (PS9N, PS14, PS25F) and intermediate (PS2) to weak (PS6A and PS11A). We did not observe a significant correlation of IgG antibodies with the magnitude of cellular immune responses. Conclusions: Immunosuppressive therapy alters vaccination-induced cellular immunity in psoriasis patients. Further research is needed to clarify the mechanisms involved. Full article

Background/Objectives: Pneumococcal serotypes 1 and 5 are associated with invasive pneumococcal disease (IPD). However, data on the circulation of these serotypes in Asia following the introduction of the pneumococcal conjugate vaccine (PCV) is limited. The Lao People’s Democratic Republic (Lao PDR) introduced PCV13 into its national immunisation programme in 2013. We undertook a serosurvey to assess the IgG responses to serotypes 1 and 5 from a convenience sample of children aged under 5 years in Vientiane, Lao PDR. Methods: This cross-sectional analysis used a convenience sample of the close contacts of children under five years old who had been hospitalised with acute respiratory infections between 2013 and 2016 in Vientiane, Lao PDR. Serotype-specific IgG concentrations to serotypes 1 and 5 were measured using a modified WHO ELISA method. Results: A total of 214 participants were included, 130 of whom were unvaccinated and 84 were vaccinated with PCV13. Compared to unvaccinated participants, a higher number of PCV-vaccinated participants met the IgG threshold for IPD (≥0.35 μg/mL) [41.5% (54/130) vs. 71.4% (60/84)] for serotype 1. In contrast, for serotype 5, a similar number of participants in the PCV-vaccinated and unvaccinated group met the IgG threshold for IPD (85.7% (72/84) vs. 82.3% (107/130). Among unvaccinated children, serotype 1 IgG levels peaked at 12 and 23 months at 0.49 µg/mL (95% CIs: 0.25–0.96), while serotype 5 IgG levels were similar across age groups, ranging from 0.55 to 0.79 µg/mL. Conclusions: Our findings indicate the considerable circulation of serotypes 1 and 5 within the community in Lao PDR. Ongoing surveillance is important for informing PCV vaccination strategies. Full article

Invasive pneumococcal disease (IPD) is a serious infection caused by the bacterium Streptococcus pneumoniae (pneumococcus) that can produce a wide spectrum of clinical manifestations. The aim of this study was to analyze the comorbidity factors that influenced the mortality in patients with diabetes (D) according to IPD. A retrospective study to analyze patients with D and IPD was carried out. Based on the discharge reports from the Spanish Minimum Basic Data Set (MBDS) from 1997 to 2022, the Elixhauser Comorbidity Index (ECI) and the Charlson Comorbidity Index (CCI) were calculated to predict in-hospital mortality (IHM) in Spain. A total of 12,994,304 patients with D were included, and 84,601 cases of IPD were identified. The average age for men was 70.23 years and for women 73.94 years. In all years, ECI and CCI were larger for type 2 D than for type 1 D, with men having a higher mean than women. An association was found between risk factors ECI, age, type 1 D, COVID-19, IPD (OR = 1.31; 95% CI: 1.29–1.35; p < 0.001); CCI, age, type 1 D, COVID-19, IPD (OR = 1.45; 95% CI: 1.42–1.49; p < 0.001), and increased mortality. The IHM increased steadily with the number of comorbidities and index scores from 1997 to 2022. D remains a relevant cause of hospitalization in Spain. Comorbidities reflected a great impact on patients with D and IPD, which would mean a higher risk of mortality. Predicting mortality events and length of stay by comparing indices showed that CCI outperforms ECI in predicting inpatient death after IPD. Full article

Purpose: This study aimed to evaluate the immunological response to the 23-valent pneumococcal polysaccharide vaccine (PPV23) in patients investigated for immunodeficiencies due to recurrent infections at EPM-UNIFESP Clinical Immunology outpatient clinic. Methods: This is a longitudinal retrospective study. Data were collected from the medical records of patients between 2012 and 2020. The analyses were developed in two stages: before and after administration of the PPV23 vaccine. Results: A total of 390 patients who received the PPV23 vaccine were selected. Among those who demonstrated an adequate serological response (63.6%), there was a notable decrease in the risk of upper respiratory tract infections (URTI) by 66%, tonsillitis by 74%, otitis by 76%, sinusitis by 49%, and uncomplicated pneumonia (PNM) by 77%. For invasive infections, the risk reduction was 95% for pneumonia with parapneumonic effusion and 93% for meningitis. Conclusions: The study demonstrated a significant decrease in the risk of bacterial infections following the administration of the PPV23 vaccine in this population. Therefore, we recommend including PPV23 in the vaccination schedule following pneumococcal conjugated vaccines for patients with recurrent pneumococcal infections to enhance protection and avoid complications. Full article

Background and Objectives: Patients with heart failure (HF) are at risk of increased morbidity and mortality related to pneumococcal pneumonia, and routine vaccination with a conjugated pneumococcal vaccine (PCV) for HF patients is strongly endorsed by all major international guidelines. Despite this, data on the factors associated with vaccine uptake remain scarce. The aim of this study was to understand the demographic and clinical factors associated with vaccine uptake in patients with HF and analyze the all-cause mortality in the vaccinated and unvaccinated cohorts. Materials and Methods: Four hundred and fifty patients with HF and a reduced ejection fraction followed up at a single center were enrolled. Patients were followed up for a median of 164.0 (148.0–181.0) days. Results: In total, 193 of the 450 patients (42.9%) were vaccinated with PCV-13 at enrollment. Vaccinated patients were more likely to have an implantable device, namely an implantable cardioverter/defibrillator (ICD), cardiac resynchronization treatment (CRT) or left ventricular assist device (LVAD), and less likely to have a past medical history of hypertension and chronic obstructive pulmonary disease (COPD) at baseline. After multivariable adjustment, the presence of an ICD (OR: 3.17, 95% CI: 1.98–5.08), CRT (OR: 2.75, 95% CI: 1.45–5.20) and COPD (OR: 0.42, 95% CI: 0.19–0.94) remained as determinants of vaccination. All-cause mortality was not different across vaccinated or unvaccinated patients either in the unmatched (log-rank p = 0.67) or matched (log-rank p = 0.52) cohorts. Conclusions: The presence of implantable devices and coexisting COPD was associated with a higher and lower likelihood of vaccination with PCV-13, respectively. No difference in mortality across cohorts was observed in this observational analysis. Full article

Children with hemato-oncological diseases represent a heterogeneous population at heightened risk for vaccine-preventable diseases. Their immunosuppressed state reduces vaccine efficacy and raises safety concerns regarding live attenuated vaccines due to the risk of viral reactivation. The immunological and clinical implications of the single conditions are significantly different; therefore, specific vaccination strategies are needed. Despite the availability of vaccine guidelines for immunocompromised patients, clinical practice remains highly variable. It is generally recommended to avoid vaccinations during chemotherapy, with some exceptions for influenza, pneumococcal, and, in some countries, hepatitis B vaccines. The timing of immune recovery after chemotherapy depends on the specific treatment and most guidelines recommend administering vaccines 3–6 months after treatment cessation. Concerning HSCT, the timing of immune recovery is affected by several factors such as the HSCT platform, graft-versus-host disease (GvHD), and infections. Inactivated vaccines are typically administered 3–6 months post-HSCT, while live attenuated vaccines are delayed for at least two years. In children with asplenia or hyposplenism, recommendations focus on immunization against encapsulated bacteria, with tailored schedules based on the patient’s age and underlying condition. This paper explores the biological factors influencing vaccination efficacy and safety in pediatric hematology and oncology patients. It also provides an updated overview of the available evidence and current vaccination guidelines. Finally, this paper highlights the main clinical and research areas for further improvement to provide tailored vaccination schedules for this vulnerable population. Full article

Previous studies have shown that high-dose vitamin supplements can improve vaccine-induced immune responses and pathogen protection in the context of vitamin deficiencies. To further elucidate the influence of vitamin supplements on immune responses toward pediatric vaccines, we performed a randomized controlled clinical trial (PCVIT) of 20 healthy children 1–4 years of age in Memphis, Tennessee. Study participants received a booster vaccine for pneumococcus and a primary vaccine for hepatitis A virus with or without a high-dose, oral, liquid supplement of 10,000 IU retinyl palmitate. We found that the children enrolled in PCVIT had higher baseline vitamin levels than previously described older children and adults living in Memphis. Only one child in PCVIT had a serum retinol level of less than 0.3 µg/mL. The children frequently consumed milk and baby foods that were likely vitamin-fortified, providing an explanation for the relatively high vitamin levels. Most children in PCVIT responded well to pneumococcus and hepatitis A vaccines by pathogen-specific antibody upregulation. The one child with a serum retinol level below 0.3 µg/mL did not receive a vitamin supplement and exhibited the lowest fold-change in antibody responses toward pneumococcal serotypes. A correlation matrix encompassing demographics, vitamin levels, vaccine-induced immune responses, C-reactive protein, and total serum immunoglobulin isotypes, including IgG2 and IgA, identified variables associated with vaccination outcomes. Perhaps because children were predominantly retinol-sufficient at baseline, the high-dose vitamin A supplement exhibited no benefit to vaccine-induced immune responses. In fact, when vitamin supplemented and vitamin unsupplemented groups were compared among participants with the highest baseline retinol levels, there was a trend toward weaker vaccine-induced immune responses in the vitamin supplemented group. Results encourage the performance of larger clinical studies before high-dose vitamin supplements are recommended for populations that are otherwise vitamin-replete. Full article

Streptococcus pneumoniae (pneumococcus) is a significant human pathogen responsible for a range of diseases from mild infections to invasive pneumococcal diseases, particularly affecting children, the elderly, and immunocompromised individuals. Despite pneumococcal conjugate vaccines having reduced disease incidence, challenges persist due to serotype diversity, vaccine coverage gaps, and antibiotic resistance. This review highlights the role of LytA, a key autolysin (N-acetylmuramoyl-l-alanine amidase), in pneumococcal biology. LytA regulates autolysis, contributes to inflammation, and biofilm formation, and impairs bacterial clearance. It also modulates complement activation, aiding immune evasion. LytA expression is influenced by environmental signals and genetic regulation and is tied to competence for genetic transformation, which is an important virulence trait, particularly in meningitis. With the increase in antibiotic resistance, LytA has emerged as a potential therapeutic target. Current research explores its use in bacteriolytic therapies, vaccine development, and synergistic antibiotic strategies. Various compounds, including synthetic peptides, plant extracts, and small molecules, have been investigated for their ability to trigger LytA-mediated bacterial lysis. Future directions include the development of novel anti-pneumococcal interventions leveraging LytA’s properties while overcoming vaccine efficacy and resistance-related challenges. Human challenge models and animal studies continue to deepen our understanding of pneumococcal pathogenesis and potential treatment strategies. Full article

Background: This study investigated the humoral responses to SARS-CoV-2 in hemodialysis (HD) patients. The clearance of molecules in the blood during hemodialysis is influenced by factors such as filter pore size, flow rate, operating pressure, and treatment duration. Chronic kidney disease patients often show low antibody titers for pathogens like pneumococcus, influenza virus, and hepatitis B virus. Methods: In this study, the surrogate virus neutralization test (sVNT) for the wild type (WT) and Omicron variants, as well as spike-specific IgG levels, were measured at two time points (May 2022 and December 2023). Medical records and questionnaires were used to gather participant information. Results: A total of 26 HD patients were enrolled, including 3 on immunosuppressive therapies. A total of 8 patients had COVID-19 during the first sampling, and 19 during the second. The results showed that sVNT levels for WT decreased over time, though positivity remained at 100% during both sampling periods. In contrast, sVNT levels for Omicron increased significantly, with positivity rising from 46.2% to 75.0% (p < 0.05). Spike-specific IgG levels also increased, with positivity improving from 96.2% to 100%. Patients on immunosuppressive therapies had significantly lower sVNT levels for both WT and Omicron in the second period (p < 0.05), though no significant differences were observed during the first period. Conclusion: HD patients, particularly those on immunosuppressive therapies, showed reduced and declining neutralizing responses over time. A meta-analysis of HD patients seems necessary to determine whether all dialysis patients need COVID-19 booster vaccinations, similar to the hepatitis B vaccine, highlighting the need for targeted vaccination strategies. Full article

Background: In hospital- and community-acquired central nervous system infections, resistant Gram-positive bacteria are an increasing therapeutic challenge. The present approach does not attempt to identify rapidly bactericidal therapies for susceptible pathogens but aims to improve methods to find antibiotic regimens for multi-resistant pathogens that are effective in vivo in spite of reduced in vitro susceptibility in culture media. Methods: Antibiotic susceptibility was tested in cerebrospinal fluid (CSF) and Mueller–Hinton broth (Enterococcus faecalis, methicillin-resistant Staphylococcus aureus, Staphylococcus epidermidis) or brain–heart infusion (Streptococcus pneumoniae). Results: Minimal inhibitory concentrations (MICs) and minimal bactericidal concentrations (MBCs) were either lower in CSF than in broth or equal in CSF and broth. The difference between MICs in CSF and broth was prominent with gentamicin, levofloxacin, linezolid (staphylococci), and vancomycin (staphylococci and pneumococcus), whereas it was absent with ampicillin (E. faecalis), penicillin G (S. pneumoniae), linezolid (enterococcus and pneumococcus), and vancomycin (enterococcus). In no case was the MIC or MBC higher in CSF than in broth. Conclusions: Several antibiotics possess an antibacterial effect in CSF at lower concentrations than the MICs determined in broth, i.e., MICs in broth underestimate in situ susceptibility in CSF. Full article

Celiac disease (CD) is an autoimmune disorder caused by gluten intake in genetically predisposed individuals. This article provides an overview of the available data on the risks of infectious diseases and the mechanisms involved in CD, including a detailed analysis of vaccine efficacy, immunogenicity, and safety. The published articles were retrieved from the PubMed database using the terms “celiac disease”, “efficacy”, “hyposplenism”, “immune response”, “infections”, “immunization”, “immunogenicity”, “safety”, “vaccination”, and “vaccine”. CD can be associated with several autoimmune diseases, including selective immunoglobulin A deficiency (SIgAD), altered mucosal permeability, and hyposplenism. These conditions entail an increased risk of infections, which can be prevented by targeted vaccinations, although specific recommendations on immunization practices for subjects with CD have not been released. Regarding vaccinations, the immune response to the Hepatitis B virus (HBV) vaccine can be impaired in patients with CD; therefore, proposed strategies to elicit and maintain protective specific antibody titers are summarized. For patients with conditions that put them at risk of infections, vaccinations against Pneumococcus and other encapsulated bacteria should be recommended. Based on the available evidence, the Rotavirus vaccine offered to children could be useful in preventing CD in at-risk subjects. Overall, except for the HBV vaccine, vaccine efficacy in patients with CD is comparable to that in the general population, and no safety concerns have arisen. Full article

Background. Causing approximately 8 million deaths each year, tobacco smoking represents a significant public health concern. Evidence shows that smoking significantly impairs antibody production and immune cell activity following vaccination. Objectives. This review aims to provide a comprehensive overview of the literature regarding how smoking reduces the effectiveness of active immunization by affecting vaccine-induced immune response. Methods. This study was performed according to the PRISMA guidelines, and the protocol was registered on the PROSPERO platform (ID: CRD42024582638). PubMed, Scopus and Web of Science were consulted as bibliographic and citation databases. Studies published in Italian and English and that aimed to investigate the effects of exposure to active and passive tobacco smoking on vaccine-induced immune response were included. Results. Thirty-four studies were selected. Overall, a decrease in antibody levels and avidity and in immune cell production were observed in individuals exposed to smoke. The meta-analysis showed a weighted mean difference between smokers and non-smokers equal to 0.65 (95% CI: 0.10–1.19, p = 0.02) for vaccinations against COVID-19, influenza, pneumococcus, HBV, HPV, tetanus, pertussis, polio, haemophilus influenzae type b, measles–mumps–rubella, and recurrent urinary tract infections. Conclusions. Smoking cessation campaigns should be considered in order to increase the effectiveness of vaccination programs. Furthermore, the opportunity to adopt different vaccine dosing schemes for smokers and non-smokers, especially in acute epidemics, should be considered. Full article

Patients undergoing immune effector cell therapy (IECT) are at high risk for infections. We assessed seropositivity against pneumococcus, tetanus, and diphtheria in patients before and after IECT and the patients’ response to vaccination. We enrolled patients who underwent IECT from January 2020 to March 2022. Antibody levels for diphtheria, tetanus, and pneumococcus were measured before IECT, at 1 month, and 3–6 months after. Eligible patients were vaccinated after IECT. In non-seroprotected patients, we discontinued testing. Before IECT, most patients had seroprotective antibody levels against tetanus (68/69, 99%) and diphtheria (65/69, 94%), but fewer did against pneumococcus (24/67, 36%). After IECT, all patients had seroprotective antibody levels for tetanus at 1 month (68/68) and 3–6 months (56/56). For diphtheria, 65/65 patients (100%) had seroprotective antibody levels at 1 month, and 48/53 (91%) did at 3–6 months. For pneumococcus, seroprotective antibody levels were identified in 91% (21/23) of patients at 1 month and 79% (15/19) at 3–6 months following IECT. Fifteen patients received a pneumococcal vaccine after IECT, but none achieved seroprotective response. One patient received the tetanus-diphtheria vaccine and had a seroprotective antibody response. Because some patients experience loss of immunity after IECT, studies evaluating vaccination strategies post-IECT are needed. Full article

The inactivated quadrivalent influenza vaccine (IIV4) and the 23-valent pneumococcal polysaccharide vaccine (PPSV23) have been administered for years and could be administered concomitantly if necessary. However, the immunogenicity and safety of the concomitant administration of these two vaccines have not been well documented, especially in the Chinese population. In this study, 480 participants aged 60 years and older were randomly assigned to the concomitant administration group (C group) or the separate administration group (S group) to receive IIV4 and PPSV23 either concomitantly or separately. Blood samples were collected before and 28 days after each vaccination. The antibodies against four influenza virus strains and twenty-three pneumococcus serotypes were tested. The results showed that the geometric mean titer (GMT) ratios (C group to S group) for the four influenza strains ranged from 0.72 to 0.95, with the lower limits of the 95% confidence intervals (CIs) ranging from 0.51 to 0.75, and the geometric mean concentration (GMC) ratios for the 23 pneumococcal serotypes ranged from 0.80 to 1.00, with the lower limits of 95% CIs ranging from 0.67 to 0.86. All values met the predefined criteria for non-inferiority. The incidence of adverse events was 0.63% in the C group and 1.56% in the S group. No serious adverse events were observed. In conclusion, the immunogenicity of the concomitant administration of IIV4 and PPSV23 was non-inferior to that of the separate administration, and the safety profile was favorable in adults aged 60 years and older in China. Full article

Pneumococcal pneumonia is a significant cause of illness and death globally, particularly among young children and the elderly. The cpsB gene is involved in the biosynthesis of the capsule polysaccharide, and polymorphisms in the cpsB gene are the basis for sequetyping, a molecular biology-based approach to serotyping. In this study, we attempted the sequetyping of pneumococci directly from clinical sputum specimens collected from adult patients diagnosed with community-acquired pneumonia (CAP). We performed conventional PCR for the cpsB gene, followed by TA cloning and Sanger sequencing of the amplicon. The results showed the status of clonality of pneumococci in each specimen. We also performed real-time PCR targeting pneumococci for each specimen. It revealed a significant association between the Ct value of the real-time PCR and the clonality status of pneumococci among the specimens (p-value 0.0007 by Fisher’s exact test analysis). Specifically, when the Ct value was below 22, there was a high probability that pneumococcus existed as a single clone. Thus, this study demonstrates the possible correlation between pneumococcal clonality and bacterial load in clinical specimens, which might indicate the infection status. Full article