Global burden of vaccine-associated Guillain-Barré syndrome over 170 countries from 1967 to 2023.

Research on Guillain-Barré syndrome (GBS) as a neurological adverse effect of vaccines on a global scale is scarce, highlighting the need for further investigation to evaluate its long-term impact and associated risk factors comprehensively. Hence, this study aims to assess the global burden of vaccine-associated GBS and its associated vaccines. This study utilized data from VigiBase, the World Health Organization global database of adverse event reports of medicines and vaccines, encompassing the period from 1967 to 2023 (total reports, n = 131,255,418) to investigate vaccine-associated GBS. Reported odds ratios (ROR) and information components (IC) were analyzed to assess the association between 19 vaccines and the occurrence of vaccine-associated GBS over 170 countries. We identified 15,377 (8072 males [52.49%]) reports of vaccine-associated GBS among 22,616 reports of all drugs-cause GBS from 1978 to 2023. Cumulative reports of vaccine-associated GBS have been increasing steadily over time, with a notable surge observed since the commencement of COVID-19 vaccines administration in 2020. Most vaccines showed significant associations with GBS such as Ad5-vectored COVID-19 vaccines (ROR, 14.88; IC, 3.66), COVID-19 mRNA vaccines (ROR, 9.66; IC, 2.84), and inactivated whole-virus COVID-19 vaccines (ROR, 3,29; IC 1.69). Influenza vaccines showed the highest association (ROR, 77.91; IC 5.98). Regarding age-and sex-specific risks, the association remained similar regardless of sex, with an increased association observed with advancing age. The mean time to onset was 5.5 days. Amid the COVID-19 pandemic, the reports of GBS surged in response to widespread COVID-19 vaccination. Nonetheless, COVID-19 vaccines exhibited the lowest association compared to other vaccines. Vigilance for at least one-week post-vaccination is crucial, particularly for older adults. Further research is warranted to elucidate the underlying mechanisms linking vaccines and GBS.

Surveillance for adverse events following immunization in Hebei Province, China, 2018-2020.

The aim of this study was to analyze the incidence and characteristics of adverse events following immunization (AEFI) with post-licensure vaccines used in Hebei province from 2018 to 2020 and to evaluate the safety of vaccines. All information of AEFI was gained from national adverse event following immunization surveillance system (NAEFISS) in Hebei Province from 2018 to 2020. Descriptive epidemiology method was used to analyze the data about AEFI in Hebei province. Reporting rates of AEFI were calculated by sex, age, city, categories of AEFI, severity of AEFI, reaction categories, etc. A total of 35,999 AEFI were reported through NAEFISS, and the average annual rate was 47.64/100,000 doses. The reporting rates of common adverse reactions and rare adverse reactions were 46.37/100,000 doses and 1.05/100,000 doses. The male-to-female ratio was 1.26:1. Most of the AEFI were concentrated in the ≤1 year age group and were reported in the second quarter and third quarter. The majority of AEFI were reported to be recovered or improved, and about 62% of the AEFI occurred within 24 hours after vaccination. Vaccines associated with the highest reporting rate of AEFI were diphtheria, tetanus and acellular pertussis combined vaccine (DTaP, 170.45/100,000 doses). The reporting rate of allergic rash was found to be the highest in the adverse reactions (0.29/100,000 doses). The majority of AEFI cases were common adverse reactions, while serious rare adverse reactions caused by vaccines were extremely uncommon, and all vaccines used in Hebei Province were safe.

An evaluation of the surveillance system for monitoring and reporting adverse events following immunization in Kebbi State, Northern Nigeria: a mixed method approach.

INTRODUCTION: Despite the benefits of periodic evaluation of the vaccine safety surveillance system, no formal assessment, to our knowledge, has been conducted in Nigeria. Hence, this study evaluated the surveillance system for adverse events following immunization (AEFI) to ascertain the system's functionality to inform vaccine safety considerations and guide communication strategies for demand generation. MATERIALS AND METHODS: The study employed a mixed-method approach. Survey questionnaires were administered to 274 routine immunization service providers in Kebbi State, Northern Nigeria, and data were analyzed descriptively using SPSS. In this study, 10 Key Informant Interviews and two Focus Group Discussions were conducted with senior officers and managers at sub-national and national levels within the immunization and surveillance landscape in Nigeria. The interview recordings were cleaned minimally, transcribed, and manually analyzed thematically. Finally, methodological triangulation was done to improve research rigor and provide a better understanding of the phenomena under investigation. RESULTS: Of the respondents, 201(73.4%) reported that the surveillance system can inform vaccine safety considerations while 170(62%) reported that the AEFI surveillance system can determine the magnitude of AEFI within the population. Further, 173(63%) reported that the surveillance system can provide timely feedback about causality assessment. However, 158(58%) of the respondents stated that the surveillance system is competent in informing communication strategies to improve immunization demand. Triangulation was done which showed dissonance in AEFI surveillance and vaccine safety considerations but partial agreement in immunization demand generation. Further, AEFI surveillance system attributes' triangulation revealed agreements (convergence) on simplicity and timeliness; partial agreements on acceptability, data quality, sensitivity, flexibility, and completeness; dissonance on representativeness and silence on stability, indicating a sub-optimal performance of the AEFI surveillance system in the study setting. Finally, the study unearthed some underlying health system factors impeding the AEFI surveillance system from fully fulfilling its objectives. CONCLUSION: The AEFI surveillance system in Northern Nigeria is well established but functioning sub-optimally. Based on the study findings, the capacity to provide information on vaccine safety exists but it is not robust enough to generate sufficient and convincing vaccine safety data and guide communication strategies for vaccine demand generation, especially for new vaccines and those under emergency authorization use.

Vaccines and allergy: Back to the right places.

Hypersensitivity reactions represent one of the most common causes of hesitancy for adherence to national vaccination programs. The majority of hypersensitivity reactions after vaccination are mild, and anaphylaxis is reported to be rare, although it remains challenging to estimate the frequency attributed to each single vaccine, either because of the lower number of administered doses of less common vaccines, or the administration of simultaneous vaccine in most of the vaccination programs. Although literature remains scattered, international consensus guides clinicians in identifying patients who might need the administration of vaccines in protected environments due to demonstrated hypersensitivity to vaccine components or adjuvants. Here we provide the current guidance on hypersensitivity reactions to vaccines and on vaccination of children with allergy disorders.

Collecting and reporting adverse events in low-income settings-perspectives from vaccine trials in the Gambia.

BACKGROUND: Despite Africa's significant infectious disease burden, it is underrepresented in global vaccine clinical trials. While this trend is slowly reversing, it is important to recognize and mitigate the challenges that arise when conducting vaccine clinical trials in this environment. These challenges stem from a variety of factors peculiar to the population and may negatively impact adverse event collection and reporting if not properly addressed. METHODS: As a team of clinical researchers working within the MRCG (Medical Research Council Unit The Gambia), we have conducted 12 phase 1 to 3 vaccine trials over the past 10 years. In this article, we discuss the challenges we face and the strategies we have developed to improve the collection and reporting of adverse events in low-income settings. OUTCOME: Healthcare-seeking behaviors in the Gambia are influenced by spiritual and cultural beliefs as well as barriers to accessing orthodox healthcare; participants in trials may resort to non-orthodox care, reducing the accuracy of reported adverse events. To address this, trial eligibility criteria prohibit self-treatment and herbal product use during trials. Instead, round-the-clock care is provided to trial participants, facilitating safety follow-up. Constraints in the healthcare system in the Gambia such as limitations in diagnostic tools limit the specificity of diagnosis when reporting adverse events. To overcome these challenges, the Medical Research Council Unit maintains a Clinical Services Department, offering medical care and diagnostic services to study participants. Sociocultural factors, including low literacy rates and social influences, impact adverse event collection. Solicited adverse events are collected during home visits on paper-based or electronic report forms. Community engagement meetings are held before each study starts to inform community stakeholders about the study and answer any questions they may have. These meetings ensure that influential members of the community understand the purpose of the study and the risks and benefits of participating in the trial. This understanding makes them more likely to support participation within their communities. CONCLUSION: Conducting ethical vaccine clinical trials in resource-limited settings requires strategies to accurately collect and report adverse events. Our experiences from the Gambia offer insights into adverse event collection in these settings.

Safety and efficacy of vaccinations in patients with multiple sclerosis: a systematic review.

OBJECTIVE: The study aims to show the efficacy/effectiveness and safety of vaccinations in patients with multiple sclerosis. MATERIALS AND METHODS: This systematic review was conducted following the guidelines of the Cochrane Collaboration and the meta-analysis of observational studies in epidemiology (MOOSE). RESULTS: At the end of the review process, 133 studies were included; the bibliographic search was conducted on PubMed/Medline and Scopus, combining free text and words. CONCLUSIONS: In general, vaccinations do not seem to aggravate multiple sclerosis (MS) or increase the probability of relapse, particularly for inactivated vaccines and, in general, for the rest of the vaccines. However, it is advisable, especially for vaccines with a live attenuated virus, to carefully evaluate the risks and benefits of these vaccinations; as regards the effectiveness in relation to the drug taken, there is great variability in response. In particular, vaccinations are less effective in patients undergoing therapy with anti-CD20 and S1P modulators. At the same time, a small response is likely to be better than none. Whenever possible, vaccinations should be offered and recommended to patients with multiple sclerosis.

Pandemic Incident Management for Vaccine Safety Challenges: Victoria's Alert Advisory Group Experience.

Safe vaccines are critical for biosecurity protection, yet adverse events-rightly or wrongly attributed to immunization-potentially cause rapid loss of confidence, reduced vaccine uptake, and resurgence of preventable disease. Effective vaccine safety incident management is essential to provide assessment and lead appropriate actions to ensure vaccination programs are safe and mitigate unwarranted crisis escalation that could damage vaccine programs and the effective control of vaccine preventable disease outbreaks or pandemics. Incident management systems (IMS) are used globally to direct emergency management response, particularly for natural disasters of fire, flood, and storm. Public health is equally an emergency response and can therefore benefit from these command control constructs. While examples of IMS for outbreak response and mass immunization logistics exist, there is little to no information on their use in vaccine safety. We describe Australia's vaccine safety Alert Advisory Group establishment in Victoria during the COVID-19 pandemic and onward embedding into routine practice, anticipant of new vaccines, and the next biosecurity threat.

Establishing the Vaccine Safety Health Link: A large, linked data resource for the investigation of vaccine safety concerns.

OBJECTIVE: Post-licensure vaccine safety surveillance of adverse events following immunisation is critical to ensure public safety and confidence in vaccines. This paper aims to describe the governance structure and data linkage methodology behind the establishment of the largest linked vaccine safety surveillance data resource in Australia - The Vaccine Safety Health Link (VSHL). METHODS: The Vaccine Safety Health Link contains linked records from the Australian Immunisation Register with records from hospital, perinatal, mortality, and notifiable disease datasets in near real-time. Linkage is done by the Centre for Victorian Data Linkage who receive the datasets in an identifiable format which then undergo standardisation, enrichment, linkage, quality assurance and de-identification, prior to being supplied for analysis. RESULTS: The VSHL data resource allows sensitive and rapid analysis of a broad spectrum of suspected adverse events to ensure the safety of all vaccines administered. It is also used to refute spurious concerns where no associations are found, upholding trust, and maintaining vaccine confidence. CONCLUSIONS: The Vaccine Safety Health Link's surveillance design complements existing vaccine safety surveillance methods. Challenges encountered and lessons learnt using Vaccine Safety Health Link would benefit linkage projects globally. IMPLICATIONS FOR PUBLIC HEALTH: In its first two years, The Vaccine Safety Health Link has been used for 14 vaccine safety investigations. Studies into these conditions would not have otherwise been possible. The Vaccine Safety Health Link also partners with the Global Vaccine Data Network™ for approved collaborative studies with a combined population of over 300 million people.

Supporting vaccine (co)-administration decisions: Development and validation of a tool for assessing the risk of severe outcomes due to lower respiratory tract infections.

OBJECTIVE: To develop and validate a score to predict the 90-day risk of hospitalization/death in patients with low respiratory tract infections (LRTIs) with the aim to support clinical decision making on vaccine (co)-administration. METHODS: We formed a cohort of patients aged 18 years or older being diagnosed with LRTIs in the period between January 1, 2012 and December 31, 2022. Each patient was followed until occurrence of respiratory-related hospitalization/death up to the end of the study period (December 31, 2022). Along with age and sex, forty determinants were adopted to assemble the respiratory tract infection (RTI)-Health Search (HS) core using the development sub-cohort. The prediction accuracy of the score was therefore assessed in the validation sub-cohort. RESULTS: We identified 252,319 patients being diagnosed with LRTIs (females: 54.7 %; mean age: 60 (SD:18.1)). When the risk of LRTIs-related hospitalizations/deaths was estimated via RTI-HScore, its predicted value was equal to 1.4 % over a 90-day event horizon. The score showed explained variation and discrimination accuracy were equal to 45 % (95 % CI: 44-47 %) and 81 % (95 % CI: 79-84 %), respectively. The calibration slope did not significantly differ from the unit (p = 0.8314). CONCLUSIONS: The RTI-HScore was featured by good accuracy for prediction of LRTIs-related complications over a 90-day follow-up. Such a tool might therefore support general practitioners to enhance patients' care by facilitating approaches for (co)-administration of vaccines for respiratory infections through a score-based decision support system.

Global burden of vaccine-associated rheumatic diseases and their related vaccines, 1967-2023: A comprehensive analysis of the international pharmacovigilance database.

Vaccine-associated rheumatic diseases are rare but one of the most feared adverse drug reactions (ADRs). However, this topic has been investigated less with large-scale data in the literature. With the rapid progress in the development and approval of vaccines during the pandemic, public concerns regarding their safety have been raised. To assess the global and regional burden, long-term trends, and potential risk factors of vaccines-associated six types of rheumatic diseases (ankylosing spondylitis [AS], polymyalgia rheumatica [PMR], rheumatoid arthritis [RA], Sjögren's syndrome, Systemic lupus erythematosus [SLE], Systemic scleroderma), this study conducted disproportionality analysis based on the reports from the World Health Organization International Pharmacovigilance Database documented between 1967 and 2023 (n for total reports = 131 255 418) across 156 countries and territories. We estimated the reporting odds ratio (ROR) and information component (IC) to determine the disproportionality signal for rheumatic diseases. Of 198 046 reports of all-cause rheumatic diseases, 14 703 reports of vaccine-associated rheumatic diseases were identified. While the reporting counts have gradually increased over time globally, we observed a dramatic increase in reporting counts after 2020, potentially due to a large portion of reports of COVID-19 mRNA vaccine-associated rheumatic diseases. The disproportionality signal for rheumatic diseases was most pronounced in HBV vaccines (ROR, 4.11; IC025, 1.90), followed by COVID-19 mRNA (ROR, 2.79; IC025, 1.25), anthrax (ROR, 2.52; IC025, 0.76), papillomavirus (ROR, 2.16; IC025, 0.95), encephalitis (ROR, 2.01; IC025, 0.58), typhoid (ROR, 1.91; IC025, 0.44), influenza (ROR, 1.49; IC025, 0.46), and HAV vaccines (ROR, 1.41; IC025, 0.20). From age- and sex-specific perspective, young females and old males are likely to have vaccine-associated rheumatic disease reports. Furthermore, overall vaccines showed a disproportionality signal for PMR (IC025, 3.13) and Sjögren's syndrome (IC025, 0.70), systemic scleroderma (IC025, 0.64), specifically while the COVID-19 mRNA vaccines are associated with all six types of diseases. Although multiple vaccines are associated with rheumatic disease reports, healthcare providers should be aware of the potential of autoimmune manifestations following vaccination, particularly the COVID-19 mRNA and HBV vaccines, and take into account for risk factors associated with these ADRs. Most ADRs exhibited an average time to onset of 11 days, underscoring the significance of monitoring and timely management by clinicians.

Current Approaches in Postapproval Vaccine Safety Studies Using Real-World Data: A Systematic Review of Published Literature.

PURPOSE: Well-designed observational postmarketing studies using real-world data (RWD) are critical in supporting an evidence base and bolstering public confidence in vaccine safety. This systematic review presents current research methodologies in vaccine safety research in postapproval settings, technological advancements contributing to research resources and capabilities, and their major strengths and limitations. METHODS: A comprehensive search was conducted using PubMed to identify relevant articles published from January 1, 2019, to December 31, 2022. Eligible studies were summarized overall by study design and other study characteristics (eg, country, vaccine studied, types of data source, and study population). An in-depth review of select studies representative of conventional or new designs, analytical approaches, or data collection methods was conducted to summarize current methods in vaccine safety research. FINDINGS: Out of 977 articles screened for inclusion, 135 were reviewed. The review shows that recent advancements in scientific methods, digital technology, and analytic approaches have significantly contributed to postapproval vaccine safety studies using RWD. "Near real-time surveillance" using large datasets (via collaborative or distributed databases) has been used to facilitate rapid signal detection that complements passive surveillance. There was increasing appreciation for self-controlled case-only designs (self-controlled case series and self-controlled risk interval) to assess acute-onset safety outcomes, artificial intelligence, and natural language processing to improve outcome accuracy and study timeliness and emerging artificial intelligence-based analysis to capture adverse events from social media platforms. IMPLICATIONS: Continued development in the area of vaccine safety research methodologies using RWD is warranted. The future of successful vaccine safety research, especially evaluation of rare safety events, is likely to comprise digital technologies including linking RWD networks, machine learning, and advanced analytic methods to generate rapid and robust real-world safety information.

Childhood PFAS exposure and immunotoxicity: a systematic review and meta-analysis of human studies.

BACKGROUND: Exposure to poly- and perfluoroalkyl substances (PFAS) may affect infant and childhood health through immunosuppression. However, the findings of epidemiological literature examining relationships between prenatal/childhood PFAS exposure and vaccine response and infection in humans are still inconclusive. The aim of this review was to examine the effects of PFAS exposure on vaccine antibody response and infection in humans. METHODS: The MEDLINE/Pubmed database was searched for publications until 1 February 2023 to identify human studies on PFAS exposure and human health. Eligible for inclusion studies had to have an epidemiological study design and must have performed logistic regression analyses of gestational or childhood exposure to PFAS against either antibody levels for pediatric vaccines or the occurrence of children's infectious diseases. Information on baseline exposure to PFAS (in ng/mL), the age of PFAS exposure (gestational or in years), and the outcome was measured, potentially leading to multiple exposure-outcome comparisons within each study was collected. Percentage change and standard errors of antibody titers and occurrence of infectious diseases per doubling of PFAS exposure were calculated, and a quality assessment of each study was performed. RESULTS: Seventeen articles were identified matching the inclusion criteria and were included in the meta-analysis. In general, a small decrease in antibody response and some associations between PFAS exposure and childhood infections were observed. CONCLUSIONS: This meta-analysis summarizes the findings of PFAS effects on infant and childhood immune health. The immunosuppression findings for infections yielded suggestive evidence related to PFAS exposure, particularly PFOS, PFOA, PFHxS, and PFNA but moderate to no evidence regarding antibody titer reduction. SYSTEMATIC REVIEW REGISTRATION: The research protocol of this systematic review is registered and accessible at the Open Science Framework ( https://doi.org/10.17605/OSF.IO/5M2VU ).

Global burden of vaccine-associated hepatobiliary and gastrointestinal adverse drug reactions, 1967-2023: A comprehensive analysis of the international pharmacovigilance database.

Although previous studies have focused on hepatobiliary and gastrointestinal adverse drug reactions (ADRs) associated with COVID-19 vaccines, literature on such ADRs with other vaccines is limited, particularly on a global scale. Therefore, we aimed to investigate the global burden of vaccine-associated hepatobiliary and gastrointestinal ADRs and identify the vaccines implicated in these occurrences. This study utilized data from the World Health Organization (WHO) international pharmacovigilance database to extract reports of vaccine-associated hepatobiliary and gastrointestinal ADRs from 1967 to 2023 (total reports = 131 255 418). Through global reporting counts, reported odds ratios (ROR) with 95% confidence interval (CI), and information components (IC) with IC0.25, the study examined the association between 16 vaccines and the incidence of hepatobiliary and gastrointestinal ADRs across 156 countries. Of the 6 842 303 reports in the vaccine-associated ADRs, 10 786 reports of liver injury, 927 870 reports of gastrointestinal symptoms, 2978 reports of pancreas and bile duct injury, and 96 reports of intra-abdominal hemorrhage between 1967 and 2023 were identified. Most hepatobiliary and gastrointestinal ADRs surged after 2020, with the majority of reports attributed to COVID-19 messenger RNA (mRNA) vaccines. Hepatitis A vaccines exhibited the highest association with liver injury (ROR [95% CI]: 10.30 [9.65-10.99]; IC [IC0.25]: 3.33 [3.22]), followed by hepatitis B, typhoid, and rotavirus. Specifically, ischemic hepatitis had a significant association with both Ad5-vectored and mRNA COVID-19 vaccines. Gastrointestinal symptoms were associated with all vaccines except for tuberculosis vaccines, particularly with rotavirus (11.62 [11.45-11.80]; 3.05 [3.03]) and typhoid (11.02 [10.66-11.39]; 3.00 [2.96]). Pancreas and bile duct injury were associated with COVID-19 mRNA (1.99 [1.89-2.09]; 0.90 [0.83]), MMR (measles, mumps, and rubella), and papillomavirus vaccines. For intra-abdominal hemorrhage, inactivated whole-virus COVID-19 vaccines (3.93 [1.86-8.27]; 1.71 [0.41]) had the highest association, followed by COVID-19 mRNA (1.81 [1.42-2.29]; 0.77 [0.39]). Most of these ADRs had a short time to onset, within 1 day, and low mortality rate. Through a global scale database, the majority of ADRs occurred within 1 day, emphasizing the importance of healthcare workers' vigilant monitoring and timely management.

Anti-platelet factor 4 immunothrombotic syndromes.

Anti-platelet factor 4 immunothrombotic syndromes comprise a group of disorders that include heparin-induced thrombocytopenia and vaccine-induced immune thrombocytopenia and thrombosis. These are highly prothrombotic, immunological disorders characterised by specific clinical and pathological criteria which include thrombocytopenia and thrombosis. While they are predominantly triggered by heparin and the adenoviral vector vaccines, respectively, other provoking factors have been described, as well as spontaneous forms. The unexplained co-occurrence of thrombocytopenia with thrombosis should raise suspicion and prompt testing. This nutshell review discusses the pathophysiology, presenting features and diagnostic criteria for these conditions.

Global estimates on the reports of vaccine-associated myocarditis and pericarditis from 1969 to 2023: Findings with critical reanalysis from the WHO pharmacovigilance database.

Due to the limitation of previous studies examining adverse reports of myocarditis and pericarditis associated with vaccines other than the COVID-19 vaccine, there are challenges in establishing a comprehensive understanding of vaccine safety on a global scale. Hence, the objective of this study was to examine the worldwide burden of vaccine-associated pericarditis and myocarditis and the vaccines associated with these indications. This study utilized the World Health Organization international pharmacovigilance database, from which records of vaccine-associated pericarditis and myocarditis between 1969 and 2023 were extracted (over 130 million reports). We calculated global reporting counts, reported odds ratios (RORs), and information components (ICs) to discern the association between 19 vaccines and the occurrence of pericarditis and myocarditis across 156 countries and territories. We identified 49 096 reports (male, n = 30 013) of vaccine-associated pericarditis and myocarditis among 73 590 reports of all-cause pericarditis and myocarditis. There has been a significant increase in reports of vaccine-related cardiac adverse events over time, with a noteworthy surge observed after 2020, attributed to cases of pericarditis associated with COVID-19 mRNA vaccines. Smallpox vaccines were associated with most pericarditis and myocarditis reports (ROR: 73.68 [95% CI, 67.79-80.10]; IC [IC0.25]: 6.05 [5.91]), followed by COVID-19 mRNA vaccine (37.77 [37.00-38.56]; 3.07 [3.05]), anthrax vaccine (25.54 [22.37-29.16]; 4.58 [4.35]), typhoid vaccine (6.17 [5.16-7.38]; 2.59 [2.29]), encephalitis vaccine (2.00 [1.48-2.71]; 0.99 [0.47]), influenza vaccine (1.87 [1.71-2.04]; 0.90 [0.75]), and Ad5-vectored COVID-19 vaccine (1.40 [1.34-1.46]; 0.46 [0.39]). Concerning age and sex-specific risks, reports of vaccine-associated pericarditis and myocarditis were more prevalent among males and in older age groups. The age group between 12 and 17 years exhibited significant sex disproportion. Most of these adverse events had a short time to onset (median time: 1 day) and fatality rate was 0.44%. Our analysis of global data revealed an increase in pericarditis and myocarditis reports associated with vaccines, particularly live vaccines like smallpox and anthrax, notably in young males. While these adverse events are generally rare and mild, caution is warranted, especially for healthcare workers, due to potential myocardial injury-related in-hospital mortality. Further study with validated reporting is crucial to enhance accuracy in evaluating the correlation between vaccines and cardiac conditions for preventive measures.

Vaccine-induced strain replacement: theory and real-life implications.

The value of preventive medicine is superior to treatment with vaccinations occupying high priority. Nevertheless, heavy pressure has started to form in regard to strains not included in vaccines contributing to the changing epidemiology of pathogen subtypes leading to 'vaccine-induced strain replacement'. Among other mechanisms, increasing fitness of nonvaccine strains and metabolic shifts in the subtypes have been described. Classical examples include pneumococcal infections and viral diseases, such as the human papilloma virus. Recently, it has been described in SARS-CoV-2, leading to the emergence of new subtypes, such as Omicron and Delta variants. The phenomenon has also been reported in Mycobacterium tuberculosis, Neisseria meningitidis and rotavirus. This study addresses the concepts, examples and implications of this phenomenon.

[Box: see text].

Parents' attitudes towards the No Jab No Play legislation in Western Australia: a mixed methods study.

BACKGROUND: Mandates provide a relatively cost-effective strategy to increase vaccinate rates. Since 2014, five Australian states have implemented No Jab No Play (NJPlay) policies that require children to be fully immunised to attend early childhood education and childcare services. In Western Australia, where this study was conducted, NJNPlay legislation was enacted in 2019. While most Australian families support vaccine mandates, there are a range of complexities and unintended consequences for some families. This research explores the impact on families of the NJNPlay legislation in Western Australia (WA). METHODS: This mixed-methods study used an online parent/carer survey (n = 261) representing 427 children and in-depth interviews (n = 18) to investigate: (1) the influence of the NJNPlay legislation on decision to vaccinate; and (2) the financial and emotional impacts of NJNPlay legislation. Descriptive and bivariate tests were used to analyse the survey data and open-ended questions and interviews were analysed using reflexive thematic analysis to capture the experience and the reality of participants. RESULTS: Approximately 60% of parents intended to vaccinate their child. Parents who had decided not to vaccinate their child/ren were significantly more likely to experience financial [p < 0.001] and emotional impacts [p < 0.001], compared to those who chose to vaccinate because of the mandate. Qualitative data were divided with around half of participants supporting childhood immunisation and NJNPlay with others discussing concerns. The themes (a) belief in the importance of vaccination and ease of access, (b) individual and community protection, and (c) vaccine effectiveness, safety and alternatives help understand how parents' beliefs and access may influence vaccination uptake. Unintended impacts of NJNPlay included: (a) lack of choice, pressure and coercion to vaccinate; (b) policy and community level stigma and discrimination; (c) financial and career impacts; and (d) loss of education opportunities. CONCLUSIONS: Parents appreciation of funded immunisation programs and mandates which enhance individual and community protection was evident. However for others unintended consequences of the mandate resulted in significant social, emotional, financial and educational impacts. Long-term evidence highlights the positive impact of immunisation programs. Opinions of impacted families should be considered to alleviate mental health stressors.

A systematic review and expert Delphi Consensus recommendation on the use of vaccines in patients receiving dupilumab: A position paper of the American College of Allergy, Asthma and Immunology.

BACKGROUND: Dupilumab is a monoclonal antibody that targets the interleukin (IL)-4 receptor alpha subunit, thus blocking the effects of IL-4 and IL-13, and has shown efficacy in treating various conditions including asthma, atopic dermatitis, eosinophilic esophagitis, and others. Because of its immune modulatory effects, clinical trials that studied dupilumab did not allow patients to receive live vaccines during the clinical trials because of an abundance of caution, and thus package inserts recommend that patients who are being treated with dupilumab should avoid live vaccines. Because dupilumab is now approved for use in patients from 6 months of age for the treatment of atopic dermatitis, this reported contraindication is now posing a clinical dilemma for patients and clinicians. OBJECTIVE: To perform a systematic review of literature on the safety and efficacy of vaccinations in patients who are receiving dupilumab and to provide expert guidance on the use of vaccines in patients who are receiving dupilumab. METHODS: A systematic review of the literature was performed, and an expert Delphi Panel was assembled. RESULTS: The available literature on patients who received vaccinations while using dupilumab overall suggests that live vaccines are safe and that the vaccine efficacy, in general, is not affected by dupilumab. The expert Delphi panel agreed that the use of vaccines in patients receiving dupilumab was likely safe and effective. CONCLUSION: Vaccines (including live vaccines) can be administered to patients receiving dupilumab in a shared decision-making capacity.

Global and regional burden of vaccine-induced thrombotic thrombocytopenia, 1969-2023: Comprehensive findings with critical analysis of the international pharmacovigilance database.

OBJECTIVE: The scarcity of studies on vaccine-induced thrombosis and thrombocytopenia syndrome (TTS) limits the comprehensive understanding of vaccine safety on a global scale. Therefore, the objective of this study is to assess the global burden of vaccine-induced TTS, identify the vaccines most associated with it, and suggest clinical implications regarding vaccination. METHODS: This study employed the World Health Organization international pharmacovigilance database, extracting records of vaccine-induced immune thrombotic thrombocytopenia from 1969 to 2023 (total reports, n > 130 million). Global reporting counts, reported odds ratios (ROR), and information components (IC) were calculated to identify the association between 19 vaccines and the occurrence of vaccine-induced TTS across 156 countries. RESULTS: We identified 24 233 cases (male, n = 11 559 [47.7%]) of vaccine-induced TTS among 404 388 reports of all-cause TTS. There has been a significant increase in reports of vaccine-induced TTS events over time, with a noteworthy surge observed after 2020, attributed to cases of TTS associated with COVID-19 vaccines. Measles, mumps, and rubella (MMR) vaccines were associated with most TTS reports (ROR [95% confidence interval], 2.87 [2.75-3.00]; IC [IC0.25], 1.51 [1.43]), followed by hepatitis B (HBV, 2.23 [2.07-2.39]; 1.15 [1.03]), rotavirus diarrhea (1.95 [1.78-2.13]; 0.81 [0.53]), encephalitis (1.80 [1.50-2.16]; 0.84 [0.53]), hepatitis A (1.67 [1.50-1.86]; 0.73 [0.55]), adenovirus Type 5 vector-based (Ad5-vectored) COVID-19 (1.64 [1.59-1.68]; 0.69 [0.64]), pneumococcal (1.57 [1.49-1.66]; 0.65 [0.56]), and typhoid vaccines (1.41 [1.12-1.78]; 0.49 [0.11]). Concerning age and sex-specific risks, reports of vaccine-induced TTS were more associated with females and younger age groups. The age group between 12 and 17 years exhibited significant sex disproportion. Most of these adverse events had a short time to onset (days; mean [SD], 4.99 [40.30]) and the fatality rate was 2.20%, the highest rate observed in the age group over 65 years (3.79%) and lowest in the age group between 0 and 11 years (0.31%). CONCLUSION: A rise in vaccine-induced TTS reports, notably MMR, HBV, and rotavirus diarrhea vaccines, was particularly related to young females. Ad5-vectored COVID-19 vaccines showed comparable or lower association with TTS compared to other vaccines. Despite the rarity of these adverse events, vigilance is essential as rare complications can be fatal, especially in older groups. Further studies with validated reporting are imperative to improve the accuracy of assessing the vaccine-induced TTS for preventive interventions and early diagnosis.

Global and regional burden of vaccine-associated facial paralysis, 1967-2023: Findings from the WHO international pharmacovigilance database.

The scarce and conflicting data on vaccine-associated facial paralysis limit our understanding of vaccine safety on a global scale. Therefore, this study aims to evaluate the global burden of vaccine-associated facial paralysis and to identify the extent of its association with individual vaccines, thereby contributing to the development of a more effective vaccination program. We used data on vaccine-associated facial paralysis from 1967 to 2023 (total reports, n = 131 255 418 418) from the World Health Organization International Pharmacovigilance Database. Global reporting counts, reported odds ratios (ROR), and information components (ICs) were computed to elucidate the association between the 16 vaccines and the occurrence of vaccine-associated facial paralysis across 156 countries. We identified 26 197 reports (men, n = 10 507 [40.11%]) of vaccine-associated facial paralysis from 49 537 reports of all-cause facial paralysis. Vaccine-associated facial paralysis has been consistently reported; however, a pronounced increase in reported incidence has emerged after the onset of the coronavirus disease 2019 (COVID-19) pandemic, which is attributable to the COVID-19 mRNA vaccine. Most vaccines were associated with facial paralysis, with differing levels of association, except for tuberculosis vaccines. COVID-19 mRNA vaccines had the highest association with facial paralysis reports (ROR, 28.31 [95% confidence interval, 27.60-29.03]; IC, 3.37 [IC0.25, 3.35]), followed by encephalitis, influenza, hepatitis A, papillomavirus, hepatitis B, typhoid, varicella-zoster, meningococcal, Ad-5 vectored COVID-19, measles, mumps and rubella, diphtheria, tetanus toxoids, pertussis, polio, and Hemophilus influenza type b, pneumococcal, rotavirus diarrhea, and inactivated whole-virus COVID-19 vaccines. Concerning age- and sex-specific risks, vaccine-associated facial paralysis was more strongly associated with older age groups and males. The serious adverse outcome and death rate of vaccine-associated facial paralysis were extremely low (0.07% and 0.00%, respectively). An increase in vaccine-induced facial paralysis, primarily owing to COVID-19 mRNA vaccines, was observed with most vaccines, except tuberculosis vaccines. Given the higher association observed in the older and male groups with vaccine-associated facial paralysis, close monitoring of these demographics when administering vaccines that are significantly associated with adverse reactions is crucial.