Search Results (181)

Background and aims: Pneumococcal infections, primarily caused by Streptococcus pneumoniae, pose significant global public health challenges, particularly in vulnerable populations. In Saudi Arabia, the introduction of pneumococcal vaccination has been a crucial step towards its prevention. However, gaps in public knowledge and attitudes toward the vaccine may hinder its effectiveness. Recent studies indicate a lack of awareness about the benefits of pneumococcal vaccination, suggesting a need for further investigation. This study determined the knowledge, attitudes, and practices (KAP) of Saudi residents regarding pneumococcal infection and vaccination. Study design and Methods: This observational cross-sectional study was conducted across Saudi Arabia from November 2024 to March 2025. Data were collected through a self-administered online questionnaire designed to evaluate KAP towards pneumococcal infection and vaccination. The sample size was calculated to be 385 participants. The questionnaire underwent expert validation and a pilot study to ensure clarity and reliability. The questionnaire was distributed via social media platforms to collect the data. Data management was conducted using Microsoft Excel, and statistical analysis was performed using Statistical Package for Social Sciences (SPSS) software version 26. Results: This study included 1230 participants of whom 630 (51.2%) were females and 1075 (87.4%) were Saudi citizens. Almost half of the participants (50.2%) were aged 18–30 years, and 498 (40.5%) were married. The average knowledge score was 58.6%, indicating a moderate level of understanding among the participants regarding pneumococcal infection. Also, the average attitudes score was 70.6%, reflecting a generally positive outlook towards the importance of pneumococcal vaccination and its potential to limit infection spread. In addition, the average practices score was 68%, indicating a fairly good level of behaviors regarding vaccination practices. Statistical analyses showed that demographic factors and clinical characteristics significantly shape individuals’ KAP towards pneumococcal infection and vaccination. Conclusions: This study highlights the critical need to improve KAP regarding pneumococcal infections and vaccinations among Saudi residents and could help in developing more targeted and effective public health interventions to protect Saudi residents from pneumococcal infections. Full article

Background and Aim: Pneumococcal pneumonia is a major cause of death globally, emphasizing the importance of vaccination, especially in low- and middle-income countries. In Iran, the 13-valent pneumococcal conjugate vaccine (PCV13) is available exclusively through private healthcare systems, resulting in a lack of studies on the prevalence of Streptococcus pneumoniae (S. pneumoniae) serotypes among vaccinated children. This research aimed to explore and compare the prevalence of nasopharyngeal pneumococcal carriage, serotype distribution, and antibiotic resistance patterns in healthy PCV13-vaccinated and -unvaccinated children. Methods: From August 2023 to November 2024, a multi-center, cross-sectional observational study was conducted in Tehran, Iran. This study included 204 nasopharyngeal samples collected from children aged from 18 to 59 months, involving both cases of children vaccinated with PCV13 and unvaccinated populations. S. pneumoniae was identified through a combination of culture methods and biochemical tests, confirmed by real-time PCR. Serotyping was achieved using cpsB sequencing, and the minimum inhibitory concentration method was employed to assess antibiotic resistance. Results: This study revealed similar S. pneumoniae carriage rates between PCV13-vaccinated and -unvaccinated Iranian children (20.6% vs. 21.6%). Serotypes 23F and 19F were prevalent in unvaccinated children, while 15B/15C was more prevalent in PCV13-vaccinated children. The included S. pneumoniae serotypes in PCV13 were detected more in the unvaccinated group. PCV13-vaccinated children exhibited no penicillin-resistant pneumococcal isolates, although four isolates were non-susceptible in unvaccinated children. Both groups showed substantial resistance to erythromycin and SXT. Previous respiratory infections, daycare attendance, residence in Tehran, and a history of antibiotic consumption increased the risk of pneumococcal carriage. Conclusions: PCV13 vaccination influences pneumococcal serotype distribution and antimicrobial susceptibility, although there was no significant difference regarding carriage rates between vaccinated and unvaccinated groups. These findings highlight the critical importance of vaccination in reducing invasive serotypes and antimicrobial resistance in children under five years old, emphasizing the importance of national PCV vaccination programs alongside continuous serotype surveillance. 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: Clinical trials and serological studies have demonstrated that vaccine-induced antibodies can cross-react with some non-vaccine serotypes. However, there are limited longitudinal data on the impact of pneumococcal conjugate vaccines (PCV) on cross-reactive serotypes after implementation in immunization programs. This study examines the impact of PCVs on pneumococcal disease cases due to potential cross-reactive serotypes. Methods: Eleven countries with serotyped invasive pneumococcal disease (IPD) surveillance data that had introduced PCV10 or PCV13 were identified. The analysis focused on IPD cases due to serotypes included in PCV10 and PCV13 (PCV10/13 VTs: 6B, 9V, 19F, 23F; PCV13 only VTs: 6A, 19A) and to vaccine-related serotypes (VRTs: 6C, 9N, 23A, 23B) that may be immunologically related to VTs in children under 5 years old. For each country, the number of IPD cases were charted over time according to serogroup. Results: Following PCV introduction, reductions in VT IPD cases were observed in all countries, while some VRT IPD cases remained unchanged or increased. Serotype 19A cases declined in PCV13 countries but increased in countries that introduced PCV10. VRT 6C cases rose in PCV10 countries but showed minimal change in PCV13 countries. In PCV13 countries, 9N cases remained unchanged while 23A and 23B experienced modest increases. Conclusions: The inclusion of VT 19A in PCV13, but not in PCV10, may account for the significant increase in VRT 19A cases in PCV10 countries. The slight change in VRT 6C cases in PCV13 countries compared to the significant rise in PCV10 countries suggests that PCV13 provides cross-protection for serotype 6C through serotype 6A. Cross-protection could not be determined for other VRTs, as their cases increased or remained unchanged or had insufficient data for evaluation. Full article

Background: The introduction of biological drugs into clinical practice for the treatment of children with systemic juvenile idiopathic arthritis (sJIA) allows disease control but increases the risk of infectious events. Infectious events cause immunosuppressive therapy interruptions, leading to disease flare and life-threatening complications, namely macrophage activation syndrome. Our study aimed to evaluate the efficacy and safety of simultaneous vaccination against pneumococcal and Haemophilus influenzae type b (Hib) in children with sJIA. Methods: This study included 100 sJIA patients receiving immunosuppressive therapy who were simultaneously vaccinated against pneumococcal and Haemophilus influenzae type b (Hib) infections. The mean age of disease onset was 5.5 years. The median age at vaccination was 10 ± 4.5 years. Clinical and laboratory parameters of sJIA activity, immunization efficacy, and safety, including anti-SP and anti-Hib IgG antibodies, as well as all vaccination-related adverse events (AEs), were recorded in every patient before, 3 weeks after, and 6 months after vaccination. Results: At the time of vaccination, 29% of patients did not meet the criteria for the inactive disease stage, as defined by C. Wallace: active joints were present in 34.5% of patients, systemic manifestations (rash and/or fever) were present in 41.3%, and 24.2% of patients had solely inflammatory laboratory activity. The protective titer of anti-SP and anti-Hib IgG antibodies was detected in the majority of patients 3 weeks after vaccination (100% and 93%, respectively). The results remained unchanged (99% and 92%, respectively) for 6 months of follow-up, compared to the baseline (91% and 37%, p = 0.000001). Anti-SP IgG and anti-Hib titers raised from 48.3 (18.2; 76.5) and 0.64 (0.3; 3.2) U/mL at the baseline to 103.5 (47.3; 185.4) and 4 (3.5; 4.2) U/mL at D22 and 105 (48.7; 171.8) and 4 (3.8; 4) U/mL (EOS), respectively. Immunosuppressive therapy regimens (combined therapy or biological disease-modifying antirheumatic drug monotherapy) did not influence the immunogenic efficacy of vaccination. The incidence of infectious complications (p = 0.0000001) and antibiotic prescriptions (p = 0.0000001) decreased by more than two times, to 29.9 and 13.8 events per 100 patient months, respectively, within 6 months after vaccination—the average duration of acute infectious events was reduced by five times after immunization (p = 0.0000001). Vaccination did not lead to disease flare: the number of patients with active joints decreased by half compared to the baseline, and the number of patients with systemic manifestations decreased by six times. All vaccine-associated adverse events were considered mild and resolved within 1–2 days. Conclusions: Simultaneous vaccination against pneumococcal and Hib infections in sJIA children is an effective and safe tool that reduces the number and duration of infectious events and does not cause disease flare-ups. Full article

Background/Objectives: Pneumococcal conjugate vaccines (PCVs) were first introduced in the pediatric UK National Immunization Programme (NIP) in 2006 and subsequently led to a significant decline in invasive pneumococcal disease (IPD). In 2020, the UK NIP reduced the pediatric PCV dosing schedule from two infant doses and one toddler dose (2 + 1) to one infant dose and one toddler dose (1 + 1). This analysis evaluated the public health impact of pediatric vaccination with PCV15 versus PCV13 under a 1 + 1 schedule. Methods: A population-level compartmental model was previously adapted to the UK setting. The impact on the IPD incidence of vaccination with PCV15 versus PCV13 under a 1 + 1 schedule was evaluated over a 20-year time horizon. The uncertainty regarding the vaccine efficacy (VE) of PCV13 and PCV15 under a 1 + 1 schedule was investigated through a probabilistic sensitivity analysis, i.e., the PCV VE under a 1 + 1 schedule was assumed to be 0–24% lower than the PCV VE under a 2 + 1 schedule. Results: Relative to the initial IPD incidence, vaccination with PCV13 and PCV15 under a 1 + 1 schedule resulted in the IPD incidence in children <2 years old increasing by 11.1% (95% region: 8.4–14.5%) and 3.5% (0.2–7.7%), respectively, over the time horizon. At the end of the time horizon, in the overall population, PCV15 would lead to a 6.0% lower IPD incidence than PCV13 (10.70 IPD cases per 100,000 versus 11.38 per 100,000, respectively). Conclusions: Switching from PCV13 to PCV15 for routine pediatric vaccinations under the 1 + 1 dosing schedule in the UK led to a lower IPD incidence in both the pediatric and overall populations. Full article

The introduction of pneumococcal conjugate vaccination (PCV) into the Argentinian Childhood National Immunization Program in 2012 marked a significant milestone in public health. Our study aims to assess the impact of this intervention on pneumococcal meningitis cases, serotype distribution, and antimicrobial resistance among pediatric populations from 2013 to 2023. Specifically, we compared the early post-PCV period (2013–2014) to the late post-PCV period (2022–2023). A total of 333 pneumococcal isolates were analyzed between 2013 and 2023. Gold standard pneumococcal serotyping was performed to identify the serotypes associated with infection in children < 6 years in Argentina, and the agar dilution method was carried out to determine their profiles to antimicrobial agents. Our findings underscore the importance of PCV implementation, revealing notable shifts in pneumococcal epidemiology over the study period. The proportions of serotypes 1 (6.7% to 0.0%), 5 (5.6% to 0.0%), and 14 (7.8% to 1.8%) decreased, whereas the proportions of serotypes 10A (3.3% to 10.7%), 15B/C (2.2% to 10.7%), and 24B (0.0% to 8.9%) increased. The top five rated serotypes in the 2022–2023 period were serogroup 24 (21.4%), 10A (10.7%), 15B/C (10.7%), 23B (7.1%), and 12F (5.4%). Regarding antimicrobial resistance, we found that a total of 115/311 isolates (37%) were not suceptible to penicillin, and 2.9% were not suceptible to cefotaxime. Twenty-five percent of the isolates were microbial drug resistant, with resistance to penicillin, erythromycin, tetracycline/doxicycline, and/or cotrimoxazol. Among the PCV13 serotypes, 19A remained the most commonly associated with MDR. The non-PCV13 serotypes, particularly 24F, 24A, and 24B, were prevalent among MDR isolates. The observed trends demonstrate the need for the continued expansion of pneumococcal vaccination policies, including consideration for vaccines offering enhanced indirect protection, thereby extending benefits beyond the pediatric population to encompass adults as well. Such strategies are pivotal in reducing the burden of pneumococcal disease and safeguarding public health. Full article

Background: Chemotherapy, a cornerstone treatment for Acute Lymphoblastic Leukemia (ALL), can compromise immune function, leading to impaired immune memory function and diminished responses to revaccination. This systematic review and meta-analysis sought to evaluate the impact of chemotherapy on the immunogenicity of prior vaccinations and subsequent revaccination responses in children with ALL. Methods: A comprehensive search was conducted through PubMed, Embase, Web of Science, and Medline. Search time was 9 January 2025. R 4.4.2 was employed for data analysis. Results: A total of 29 relevant studies were identified, with 8 undergoing meta-analysis. The pooled antibody seropositive rates (SPR) for vaccines against Hepatitis B Virus (HBV), Hepatitis A Virus (HAV), diphtheria, tetanus, pertussis, measles, mumps, rubella, varicella, and Pneumococcal Conjugate Vaccine (PCV) demonstrated a statistically significant decline after chemotherapy in ALL patients (p < 0.0001). Subgroup analysis further revealed marked and heterogeneous declines in SPR after chemotherapy, with the magnitude of reduction varying significantly across vaccines—tetanus, HBV, HAV, measles, mumps, and rubella (Subgroup differences, p = 0.0037). Conclusions: This review provides an updated assessment of this critical topic, representing the first meta-analysis specifically focused on the effects of chemotherapy on different vaccines’ immunogenicity in children with ALL. Full article

Background: In the Democratic Republic of Congo (DRC), the 13-valent pneumococcal conjugate vaccine (PCV13) was introduced in 2011 through a three-dose schedule, targeting infants as part of the Expanded Program on Immunization (EPI), to reduce pneumococcal-related morbidity and mortality. The aim of this study was to determine the proportion of pneumonia and meningitis cases and deaths prevented in children under five following the introduction of this vaccine. Methods: This is a systematic review. We synthesized findings from studies carried out in the DRC between 2011 and 2023. We searched scientific articles, published and unpublished doctoral theses and conference proceedings. Only papers written in French or English and those reporting the results of original analytical studies were selected. We assessed the direct effect of PCV13 by calculating the proportion of infections avoided, using Odds Ratios or prevalence ratios related to infection or pneumococcal carriage. Results: Four studies were included in this review. Regarding pneumococcal carriage, when children received three PCV13 doses, the prevalence of carriage was reduced by 93.3% (95% CI: 86.3 to 96.6%), while a single dose did not significantly reduce the prevalence of carriage compared with children who had not received any dose. Concerning pneumonia prevention, three doses of PCV13 prevented 66.7% (95% CI: 37.2 to 82.2) of cases among vaccinated children. The proportion of meningitis attributable to S. pneumoniae prevented was 75.0% (95% CI: 6% to 93.3%) among children vaccinated with PCV13. S. pneumoniae serotypes 19F and 23F were the most frequent causes of invasive pneumonia in children. Serotypes 35B/35C, 15B/C, 10A and 11A/D were the most frequently identified causes of morbidity in Congolese children. In 2022, with PCV13 vaccination coverage at 79.0%, an estimated 113,359 cases of severe pneumonia and 17,255 pneumonia-related deaths were prevented in the DRC, with 3313 cases and 1544 deaths attributable to pneumococcal meningitis prevented. Conclusions: There is clear, but scattered, evidence of reduced colonization by S. pneumoniae and hospital admissions due to pneumococcal pneumonia and meningitis. The results also show that S. pneumoniae serotypes 35B/35C, 15B/C, 10A and 11A/D not included in PCV13 were the main cause of pneumococcal disease in unvaccinated or under-vaccinated children. These data support the need to continue improving vaccination coverage among children who are unvaccinated or incompletely vaccinated with PCV13 to reduce the burden of pneumococcal infections in the DRC. Full article

Background: The aging of the population has increased the number of frail people living in long-term care facilities, underscoring the need for continuous updates in infectious diseases prevention strategies. The aim of this study was to analyze two pneumococcal disease outbreaks in elderly residences in Gipuzkoa, northern Spain, their impact on residents, and the containment measures implemented. Material and methods: The outbreaks took place in 2023 and in 2024 in two residences of 111 and of 155 residents, respectively. Diagnosis was based on clinical criteria, radiological findings, and microbiological techniques. Pneumococcal isolates were characterized by whole-genome sequencing. Results: The outbreaks involved five and six residents, respectively. Most residents in both facilities had been vaccinated with the pneumococcal polysaccharide 23-valent vaccine (PPV23) more than five years prior. The median attack rates were 4.5% and 3.9%, lower than those reported in similar outbreaks. The adopted infection transmission prevention measures successfully limited the spread of the outbreaks. Conclusions: PPV23 vaccination did not prevent invasive pneumococcal infection in the affected residents. The vaccination of elderly people living in long-term care facilities with 20-valent and 21-valent pneumococcal conjugated vaccines should be evaluated as a new preventive measure. Full article

Acute otitis media (AOM) is a common disease among children and can be complicated by otorrhea (AOMO). In 2010, the 13-valent Pneumococcal Conjugate Vaccine (PCV13) replaced the 7-valent vaccine (PCV7) in Greece. We aimed to describe the microbiological profile of bacterial ΑOMO among children younger than 16 years across the two PCV periods in a tertiary children’s hospital. Middle ear fluid cultures from 2418 children with AOMO were collected from 2007 to 2022. Otopathogens were isolated and tested for antimicrobial susceptibility. Data were compared between the PCV7- (2007–2011) and PCV13-period (2012–2019). The most common otopathogen over the 16-year period was S. pyogenes (35.4%), followed by H. influenzae (33.8%), S. pneumoniae (26.6%), and M. catarrhalis (4.1%). Pneumococcal resistance to cefotaxime and clindamycin significantly increased from 2% to 4.5% (p = 0.019) and 16.1% to 22.8% (p = 0.039), respectively. Resistance of H. influenzae to ampicillin increased from 6.3% to 13.9% (p < 0.001). A significant reduction in cotrimoxazole-resistant S. pneumoniae from 31% to 22.4% (p = 0.012), and in clindamycin-resistant and erythromycin-resistant S pyogenes, from 17.4% to 9.3% and 21.4% to 10.8%, respectively (p ≤ 0.001), was observed. During 2013–2022, 38 S. pneumoniae serotypes were identified among 250 isolates. Serotype 3 (27.2%) and 19A (13.2%) prevailed, followed by 19F (7%). The most common causes after the shift to PCV13 are S. pyogenes and H. influenzae. However, S. pneumoniae remains an important otopathogen with significant antimicrobial resistance. Serotype 3 was mostly detected, followed by 19A. 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

Streptococcus pneumoniae remains the leading cause of community-acquired pneumonia in adults and bacterial meningitis in children worldwide. In addition to pneumonia, invasive pneumococcal diseases (IPDs), such as bacteremia and meningitis, pose a significant burden, particularly among older adults and individuals with underlying comorbidities. These diseases lead to substantial morbidity and mortality. Pneumococcal vaccination has been a cornerstone of disease prevention, reducing incidence and antimicrobial resistance. Recent advances in understanding S. pneumoniae epidemiology, genomic diversity, and the real-world impact of conjugate vaccines have driven the development and licensure of new-generation pneumococcal vaccines with expanded serotype coverage. Introducing 15-valent (PCV15), 20-valent (PCV20), and 21-valent (PCV21) conjugate vaccines has reshaped pneumococcal immunization strategies, particularly in adults, replacing previous sequential vaccine recommendations in many settings. In parallel, emerging epidemiological data and shifts in pneumococcal serotype distribution continue to influence vaccine policy decisions and immunization guidelines worldwide. In light of these advancements, adult pneumococcal vaccination recommendations continuously evolve to enhance protection in high-risk populations and optimize long-term immunity. This review provides an updated overview of the pneumococcal disease burden, the evolution of pneumococcal vaccines, and the latest immunization strategies in an expanding vaccine landscape. Additionally, we discuss future directions in pneumococcal vaccine development and the potential impact of novel vaccination approaches on public health outcomes. Full article

Background/Objectives: The clinical impact of replacing the 23-valent pneumococcal polysaccharide vaccine (PPSV23) for the vaccination of older (≥60 years) and at-risk German adults with either the 20-valent (PCV20) or 21-valent (V116) pneumococcal conjugate vaccine (PCV) was evaluated. Methods: An age- and serotype-specific transmission model was adapted to Germany to evaluate the impact of V116 versus PCV20 vaccination on pneumococcal disease (PD) incidence, including invasive pneumococcal disease (IPD) and inpatient and outpatient non-bacteremic pneumococcal pneumonia, over 10 years. A reference strategy (PPSV23 vaccination at a constant 30% vaccine coverage rate (VCR)) was compared against eight strategies varying by PCV (PCV20 vs. V116), VCR (30% vs. 60%), with or without the PCV revaccination of previously PPSV23-vaccinated adults (0% vs. 50% revaccination). Results: Vaccination with PCV20 and V116 initially decreased PD incidence, but incidence returned to pre-vaccine levels after five and eight years, respectively. Increasing the VCR to 60% prevented this resurgence. At a 10-year time horizon, V116 with 30% VCR reduced IPD cases by 9%, inpatient NBPP cases by 10%, and outpatient NBPP cases by 7% compared to the reference strategy. PCV20 with 30% VCR reduced these cases by 6%, 5%, and 4%, respectively. Increasing the VCR to 60% and revaccinating 50% of previously PPSV23-vaccinated adults further reduced IPD cases by 14% and 13% for V116, and by 9% and 9% for PCV20. Conclusions: Increasing the vaccination coverage rate to 60% and strategically revaccinating previously PPSV23-vaccinated adults significantly enhanced the effectiveness of pneumococcal vaccines, with V116 showing greater overall reductions in disease incidence compared to PCV20 or PPSV23. Full article

Background: Asthma is a heterogeneous disease characterized by variable bronchial obstruction, hyper-responsiveness, and inflammation. Evaluating the immunological changes following pneumococcal immunization in patients with different asthma endotypes is of great importance. This study aimed to evaluate the effects of PCV13 on the clinical parameters and the changes over time in the levels of the main cytokines in asthma patients. Methods: This was a single-center, open-label, non-randomized, prospective, cohort, controlled study of 31 patients aged 18 to 80 with a known diagnosis of asthma. The study subjects were given one injection of PCV13. Their clinical parameters and serum concentrations of certain Th1/Th2/Treg cytokines were assessed over a year following the vaccination. Results: Compared to the pre-vaccination period, there was an 81.5% reduction in the number of patients with asthma exacerbations (p < 0.001), a 76.5% increase in the number of patients free from hospitalization (p < 0.001), and an improvement in the level of asthma control. Positive changes were observed both in patients with T2-high and T2-low asthma; however, only those with T2-low asthma showed a significant improvement in the level of asthma control. Significant changes were reported for IFN-γ: its serum concentrations increased six weeks following the vaccination (p < 0.05), primarily in patients with T2-high asthma. Conclusions: In asthma patients, immunization with PCV13 was clinically effective, irrespective of the asthma endotype. Its clinical effects were accompanied by a reduction in the rates of exacerbations and hospitalizations and an increase in IFN-γ serum levels. This finding suggests that this cytokine plays an important role in restoring immune response in asthma patients. Full article