Diphtheria / Tetanus / Poliomyelitis (inactivated) vaccine (adsorbed) suspension for injection 0.5ml pre-filled syringes

Background/Objectives: Haematopoietic stem cell transplantation (HCT) induces profound immunosuppression, significantly increasing susceptibility to severe infections. This review examines vaccinations' necessity, timing, and efficacy post-HCT to reduce infection-related morbidity and mortality. It aims to provide a structured protocol aligned with international and national recommendations. Methods: A systematic review of current guidelines and studies was conducted to assess vaccination strategies in HCT recipients. The analysis included the timing of vaccine administration, factors influencing efficacy, and contraindications. Recommendations for pre- and post-transplant vaccination schedules were synthesised, specifically for graft-versus-host disease (GVHD), immunosuppressive therapy, and hypogammaglobulinemia. Results: Vaccination is essential as specific immunity is often lost after HCT. Inactivated vaccines are recommended to commence three months post-transplant, including influenza, COVID-19, and pneumococcal vaccines. Live attenuated vaccines remain contraindicated for at least two years post-transplant and in patients with ongoing GVHD or immunosuppressive therapy. Factors such as GVHD and immunosuppressive treatments significantly impact vaccine timing and efficacy. The review also underscores the importance of pre-transplant vaccinations and ensuring that patients' close contacts are adequately immunised to reduce transmission risks. Conclusions: Implementing a structured vaccination protocol post-HCT is critical to improving patient outcomes. Timely and effective vaccination strategies can mitigate infection risks while addressing individual patient factors such as GVHD and immunosuppression. This review highlights the need for tailored vaccination approaches to optimize immune reconstitution in HCT recipients.

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ImportanceDementia is a highly prevalent issue in older people. Whilst the prevention of dementia is a public health priority, the role of vaccinations is still largely unexplored.ObjectiveThe aim of this systematic review is to evaluate whether common adult vaccinations are associated with a reduced risk of dementia.Data sourcesPubMed, Embase and Web of Science were searched from inception to 1 January 2025.Study selectionObservational studies comparing dementia and mild cognitive impairment incidence between vaccinated and unvaccinated adults aged ≥50 years.Data extraction and synthesisFour reviewers independently extracted data and assessed study quality using the Newcastle-Ottawa Scale. Risk ratios (RRs) and 95% confidence intervals (CIs) were pooled using a random-effects model.Main outcomes and measuresIncidence of dementia, including its subtypes.ResultsTwenty-one studies (n = 104 031 186 participants) were included. Vaccination against herpes zoster was associated with a reduced risk of any dementia (RR 0.76, 95% CI 0.69-0.83) and Alzheimer's disease (RR 0.53, 95% CI 0.44-0.64). Influenza vaccination was linked to a reduction in dementia risk (RR 0.87, 95% CI 0.77-0.99), as was pneumococcal vaccination (RR 0.64, 95% CI 0.47-0.87) for Alzheimer's disease. Tetanus, diphtheria, pertussis (Tdap) vaccination was also associated with a significant reduction for any dementia (RR 0.67, 95% CI 0.54-0.83).Conclusions and relevanceAdult vaccinations, particularly against herpes zoster, influenza, pneumococcus and Tdap, are associated with a lower risk of dementia. Vaccination strategies should be incorporated into public health initiatives for dementia prevention.Registrationhttps://osf.io/x3d4f/.

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This review aimed to characterize adolescent vaccination schedules in publicly funded national immunization programs in Latin America and the Caribbean. The initial review identified vaccine type, target age and gender, dose schedule, and vaccination coverage rate (VCR) across 50 countries/territories in the region. A systematic review from January 2010-October 2023 was then conducted to identify primary data collection studies reporting VCRs. Overall, 42 webpages and 23 primary studies were identified. Among 47 countries/territories with ≥1 vaccine for adolescent immunization, human papillomavirus (HPV) vaccine was included in 45, tetanus component vaccines in 43, and meningococcal vaccines in 10. Catch-up vaccination for hepatitis B in 17, and yellow fever in all 13 endemic countries/territories. VCRs were primarily available for HPV. The findings of this review underscore the need to prioritize adolescent vaccination, improve accessibility, and strengthen tracking infrastructure to ensure comprehensive protection of this age group across the region.

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Background: Many human activities release harmful substances, contaminating the air, water, and soil. Since exposure to environmental pollutants is currently unavoidable, it is important to verify how these compounds may influence individual immune responses to vaccines. Methods: This review was conducted in accordance with the PRISMA statement. The protocol was registered on the PROSPERO platform with the following ID: CRD42024582592. We evaluated all observational, semi-experimental, and experimental studies written in both Italian and English that reported possible effects of exposure to environmental pollutants on the production of vaccine-induced antibodies. Results: Forty-two studies were included. The effects of pollutants were examined mainly in terms of antibody production in relation to mumps, measles and rubella, diphtheria and tetanus, hepatitis A and B, Haemophilus influenzae type B, influenza, tuberculosis, pertussis, Japanese encephalitis, poliomyelitis, and COVID-19 vaccines. Perfluorinated compounds were the most studied pollutants. Conclusions: Correlations between exposure to pollutants and reductions in antibody production were found in quite all the selected studies, suggesting that pollution control policies could contribute to increase the efficacy of vaccination campaigns. However, the heterogeneity of the examined studies did not allow us to perform a meta-analysis, and the literature on each type of vaccine or pollutant is still too limited to generate robust evidence. In order to confirm the findings of the present systematic review, and in the perspective of establishing possible exposure limit values for each type of pollutant, further research in this field is required.

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Background: Co-administration of vaccines can impact the immune response and safety. We aim to systematically review the current scientific literature and find evidence regarding the immunogenicity and safety of pneumococcal vaccines co-administered with common vaccines that are recommended for travelers, including hepatitis A, hepatitis B, yellow fever, tetanus, diphtheria, and acellular pertussis (Tdap), Japanese encephalitis, rabies, typhoid, or meningococcal (MCV) vaccine in adults (18 years or older). Methods: We followed the PRISMA 2020 guidelines and used the PICOS process to select the keywords. We searched PubMed, Web of Science, Scopus, EMBASE, and Google from 1 January 2000 to 30 June 2024. We included randomized controlled trials, non-randomized controlled trials, observational studies, case series, and case reports in adults, all published in English. Results: Out of 598 articles screened, 6 studies were included in our study. Three studies involved immunocompetent individuals, and three involved immunocompromised individuals. Co-administration of pneumococcal vaccine with Tdap or Hepatitis A in immunocompetent individuals was safe and immunogenic. Similar findings were reported for immunocompromised individuals when pneumococcal vaccines were co-administered with Tdap, hepatitis A, and hepatitis B. However, no reports investigated the co-administration of yellow fever, rabies, Japanese encephalitis, and typhoid. Two non-randomized studies in immunocompromised individuals had a high risk of bias. Conclusions: The studies collectively indicate that the co-administration of pneumococcal vaccines with Hepatitis A and Tdap vaccines in adult immunocompetent and immunocompromised individuals is safe and immunogenic. However, a knowledge gap remains, and further high-quality studies are needed, particularly due to the limited number of studies and the potential risk of bias.

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Poliomyelitis, preventable only through vaccination, remains a global health concern, with wild poliovirus transmission and the emergence of vaccine-derived polioviruses. The risk of further deterioration of the situation jeopardizes efforts to eradicate polio, which has been a long-term goal for the whole world. In this systematic review, an analysis of randomized clinical trials was carried out to comprehensively assess the immunogenicity and safety of various polio immunization methods in infants. Geometric mean neutralizing antibody titers (GMT) data collected after 28-31 days after immunization were used to calculate the geometric mean titer ratio (GMR), the analysis of which showed that both inactivated polio vaccine (IPV) and Sabin strain-based inactivated polio vaccine (sIPV) as primary vaccination induce high antibody rates. Average GMR rates (CI = 0.05) for the 3 types of polio were 83.08, 33.60, and 166.30 for IPV and 234.35, 44.04, and 163.13 for sIPV, with fractional IPV showing similar results. One or two doses of IPV were insufficient to induce protection levels of antibodies against type 2 poliovirus. The novel oral polio vaccine type 2 (nOPV2) and trivalent oral polio vaccine (tOPV) also demonstrated immunogenicity in establishing immunity comparable to the inactivated vaccine; the latter exhibited an average GMR of 50.75 for serotype 2. High antibody levels were also induced by combined vaccine schedules, with sIPV-sIPV-bOPV (GMR of 1,172.7 for type 1 and 887.6 for type 3) and IPV combinations with diphtheria-tetanus-whole-cell pertussis, hepatitis B and Haemophilus influenzae type b (351.2, 258.8, and 573.6 for the 3 types) or pentavalent rotavirus vaccine (354.6, 117.7, and 540.9 for the 3 types) establishing particularly high antibody levels. Analysis of adverse events presented all vaccines to be well-tolerated and safe, with a tendency for combination vaccines to have a higher frequency of local reactions and fever. While the studies presented a diverse landscape with some existing areas of concern, this review provides structured evidence supporting the safety and immunogenicity of existing polio vaccines, as well as highlighting the interchangeability of different vaccination approaches in infants. Future research should aim to provide detailed reporting of adverse events in order to facilitate more comprehensive assessment of vaccine immunogenicity and, therefore, efficacy.

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BackgroundAcute lymphoblastic leukemia is the most prevalent childhood cancer and the leading cause of cancer mortality before the age of 20. Although therapeutic advances have significantly improved survival, children and adolescents treated for acute lymphoblastic leukemia remain vulnerable to infections, largely preventable by vaccination, due to humoral and cellular immune dysfunction induced by disease and treatment.Materials and methodsThis systematic review, based on electronic databases, aims to evaluate antibody levels associated with potential protective immunity against vaccine antigens for diphtheria, pertussis, tetanus, poliomyelitis, Haemophilus influenzae type b, measles, mumps, rubella, influenza, varicella-zoster virus, yellow fever, pneumococcal, and meningococcal diseases in children and adolescents treated for acute lymphoblastic leukemia after completion of chemotherapy.ResultsA total of twenty-four studies published between 1981 and 2023 were included, comprising 1110 children and adolescents. Protective antibody levels ranged from 11% to 97% for diphtheria, 0% to 90% for pertussis, 20% to 100% for tetanus, and 11% to 95% for poliomyelitis. Haemophilus influenzae type b, protection ranged from 16.7% to 100%. Viral vaccines also showed heterogeneous responses, with protection rates of 25-79% for mumps, 16-86% for measles, 35-98% for rubella, and 23-75% for varicella-zoster virus. Antibody responses to pneumococcal and meningococcal vaccines were consistently low, with protection rates of 5-38% for pneumococcal studies and 12% in a single meningococcal study.ConclusionsThis review found a consistent and clinically relevant loss of vaccine-induced immunity in children and adolescents treated for acute lymphoblastic leukemia. The recommendation of vaccine booster doses for this vulnerable population, irrespective of serological status, may represent a more practical approach to ensuring adequate post-chemotherapy treatment protection.

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BackgroundParental vaccine hesitancy is a growing concern, and Europe has witnessed significant outbreaks of Vaccine-Preventable Diseases (VPDs) over the past two decades. Unvaccinated children are at increased risk of contracting VPDs, and the incidence of several VPDs has been on the rise. Vaccine hesitancy is a serious global health challenge. Nevertheless, the specific association between intentionally unvaccinated children and VPD outbreaks in Europe remains inadequately explored. This rapid systematic review aims to identify and examine studies focused on VPD outbreaks in Europe that involve intentionally non-vaccinated children and the factors associated with vaccine hesitancy.MethodsA rapid systematic review was conducted with a comprehensive search of electronic databases, including Medline, Embase, and Academic Search Elite. The population, exposure and outcome (PEO) framework was used to formulate the research question, inclusion and exclusion criteria. Publications from 2010 to and including August 2023 were included.ResultsOf the 330 studies initially identified, a total of nine were included in the final review. The included studies indicated that unvaccinated children due to parental refusal are contributing to outbreaks of measles, diphtheria and tetanus in the European region.ConclusionThis systematic review provides compelling evidence of an association between intentionally unvaccinated children-those unvaccinated due to parental refusal-and outbreaks of vaccine-preventable diseases (VPDs). The findings strongly suggest that this group contributes significantly to VPD outbreaks within the European region. To deepen our understanding, further research is needed to compare the role of intentionally unvaccinated children with that of other unvaccinated groups (e.g., those unvaccinated due to medical contraindications, immunosuppression, or limited access to healthcare) in the emergence and spread of VPDs.

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