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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., (© 2024. The Author(s).)

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.

Although COVID-19 vaccine uptake was high in Quebec for the primary series, vaccine acceptance decreased for the subsequent booster doses. This article presents the evolution of vaccine intention, self-reported vaccination behaviors, and vaccine hesitancy over 2 years. A series of cross-sectional surveys were conducted in Quebec between March 2020 and March 2023, with a representative sample of 3,330 adults recruited biweekly via a Web panel. Panelists could have answered multiple times over the course of the project. A cohort of respondents was created to assess how attitudes and behaviors about COVID-19 vaccines evolved. Descriptive statistics and multivariate logistic regressions were performed. Among the 1,914 individuals with no or low intention of getting vaccinated in Fall 2021 (Period 1), 1,476 (77%) reported having received at least two doses in the Winter 2023 (Period 2). Not believing in conspiracy theory (OR = 2.08, 95% CI: 1.65-2.64), being worried about catching COVID-19 (OR = 2.12, 95% CI: 1.65-2.73) and not living in a rural area (ORs of other areas are 2.27, 95% CI: 1.58-3.28; 1.66, 95% CI: 1.23-2.26; 1.82 95% CI: 1.23-2.73) were the three main factors associated with being vaccinated at Period 2. Among the 11,117 individuals not hesitant at Period 1, 1,335 (12%) became hesitant at Period 2. The three main factors significantly associated with becoming vaccine hesitant were the adherence to conspiracy theories (OR = 2.28, 95% CI: 1.95-2.66), being a female (OR = 1.67, 95% CI: 1.48-1.90) and being younger than 65 years old (the ORs for 18-34, 35-49, and 50-64 compared with 65 and over are 2.82, 95% CI: 2.32-3.44; 2.39, 95% CI: 2.00-2.86 and 1.82, 95% CI: 1.55-2.15 respectively). As the pandemic is over, monitoring the evolution of vaccine attitudes and uptake will be important.

Acute disseminated encephalomyelitis (ADEM) has been identified as an Adverse Event of Special Interest in the COVID-19 vaccine programme due to its long-standing temporal association with a wide range of other vaccines. Case reports of ADEM shortly following COVID-19 vaccination have now been documented.    There were 217 ADEM admissions in 215 individuals in the period 8th December 2020 to 31st March 2023. An increased risk of ADEM following the first dose of ChAdOx1 vaccine was observed (relative incidence (RI) = 3.13, 95% Confidence Interval (CI) [1.56-6.25]) with a vaccine attributable risk of 0.39 per million doses. When doses 1 and 2 were combined this increased risk remained just significant (1.96 [95%CI 1.01-3.82]). No significant increased risk was observed with any other vaccine or dose. This small, elevated risk after the first dose of ChAdOx1-S vaccine demonstrates how large national electronic datasets can be used to identify very rare risks and provides reassurance that any risk of ADEM following the ChAdOx1-S COVID-19 vaccination is extremely small. Given the rarity of this risk, further studies in settings with access to data on large populations should be carried out to verify these findings.

Virus-neutralizing antibodies are often accepted as a correlate of protection against infection, though questions remain about which components of the immune response protect against SARS-CoV-2 infection. In this small observational study, we longitudinally measured spike receptor binding domain (RBD)-specific and nucleocapsid (NP)-specific serum IgG in a human cohort immunized with the Pfizer BNT162b2 vaccine. NP is not encoded in the vaccine, so an NP-specific response is serological evidence of natural infection. A greater than fourfold increase in NP-specific antibodies was used as the serological marker of infection. Using the RBD-specific IgG titers prior to seroconversion for NP, we calculated a protective threshold for RBD-specific IgG. On average, the RBD-specific IgG response wanes below the protective threshold 169 days following vaccination. Many participants without a history of a positive test result for SARS-CoV-2 infection seroconverted for NP-specific IgG. As a group, participants who seroconverted for NP-specific IgG had significantly higher levels of RBD-specific IgG following NP-seroconversion. RBD-specific IgG titers may serve as one correlate of protection against SARS-CoV-2 infection. These titers wane below the proposed protective threshold approximately six months following immunization. Based on serological evidence of infection, the frequency of breakthrough infections and consequently the level of SARS-CoV-2-specific immunity in the population may be higher than what is predicted based on the frequency of documented infections.

The COVID-19 pandemic put the life science sector to the test. Vaccines were developed at unprecedented speed, benefiting from decades of fundamental research and now honoured by a Nobel Prize. However, we saw that the fruits of science were inequitably distributed. Most low- and middle-income countries were left behind, deepening the inequalities that the Sustainable Development Goals were set to reduce. We argue that the life science sector must reinvent itself to be better and more equitably prepared for the next health crisis and to ensure fair access to health across current and future generations. Our recommendations include global governance, national strategies and the role of universities and corporations. Improved and more equitable health care should be centre stage for global health action and a core mission of a reframed Life Science sector - what we call Life Science 2.0.Paper Context Main findings : During the COVID-19 pandemic the Life Science sector stepped up to the challenge, but vaccines and medicines were not equitably distributed. Added knowledge : Obstacles were identified that hindered global access to medical innovations. Global health impact for policy and action : Global and national governance, universities and the private sector should join forces to create a Life Science sector (Life Science 2.0) that affords equitable access to medical advances across geographical and generational boundaries and socio-economic strata.

High levels of COVID-19 vaccine hesitancy have been reported among Black and Latinx populations, with lower vaccination coverage among racialized versus White sexual and gender minorities. We examined multilevel contexts that influence COVID-19 vaccine uptake, barriers to vaccination, and vaccine hesitancy among predominantly racialized sexual and gender minority individuals. Semi-structured online interviews explored perspectives and experiences around COVID-19 vaccination. Interviews were recorded, transcribed, uploaded into ATLAS.ti, and reviewed using thematic analysis. Among 40 participants (mean age, 29.0 years [SD, 9.6]), all identified as sexual and/or gender minority, 82.5% of whom were racialized. COVID-19 vaccination experiences were dominated by structural barriers: systemic racism, transphobia and homophobia in healthcare and government/public health institutions; limited availability of vaccination/appointments in vulnerable neighborhoods; absence of culturally-tailored and multi-language information; lack of digital/internet access; and prohibitive indirect costs of vaccination. Vaccine hesitancy reflected in uncertainties about a novel vaccine amid conflicting information and institutional mistrust was integrally linked to structural factors. Findings suggest that the uncritical application of "vaccine hesitancy" to unilaterally explain undervaccination among marginalized populations risks conflating structural and institutional barriers with individual-level psychological factors, in effect placing the onus on those most disenfranchised to overcome societal and institutional processes of marginalization. Rather, disaggregating structural determinants of vaccination availability, access, and institutional stigma and mistrust from individual attitudes and decision-making that reflect vaccine hesitancy, may support 1) evidence-informed interventions to mitigate structural barriers in access to vaccination, and 2) culturally-informed approaches to address decisional ambivalence in the context of structural homophobia, transphobia, and racism.

Vaccination strategies that can induce a broad spectrum immune response are important to enhance protection against SARS-CoV-2 variants. We conducted a randomized, double-blind and parallel controlled trial to evaluate the safety and immunogenicity of the bivalent (5×10 10 viral particles) and B.1.1.529 variant (5×10 10 viral particles) adenovirus type-5 (Ad5) vectored COVID-19 vaccines administrated via inhalation. 451 eligible subjects aged 18 years and older who had been vaccinated with three doses inactivated COVID-19 vaccines were randomly assigned to inhale one dose of either B.1.1.529 variant Ad5 vectored COVID-19 vaccine (Ad5-nCoVO-IH group, N=150), bivalent Ad5 vectored COVID-19 vaccine (Ad5-nCoV/O-IH group, N=151), or Ad5 vectored COVID-19 vaccine (5×10 10 viral particles; Ad5-nCoV-IH group, N=150). Adverse reactions reported by 37 (24.67%) participants in the Ad5-nCoVO-IH group, 28 (18.54%) in the Ad5-nCoV/O-IH group, and 26 (17.33%) in the Ad5-nCoV-IH group with mainly mild to moderate dry mouth, oropharyngeal pain, headache, myalgia, cough, fever and fatigue. No serious adverse events related to the vaccine were reported. Investigational vaccines were immunogenic, with significant difference in the GMTs of neutralizing antibodies against Omicron BA.1 between Ad5-nCoV/O-IH (43.70) and Ad5-nCoV-IH (29.25) at 28 days after vaccination (P=0.0238). The seroconversion rates of neutralizing antibodies against BA.1 in Ad5-nCoVO-IH, Ad5-nCoV/O-IH, and Ad5-nCoV-IH groups were 56.00%, 59.60% and 48.67% with no significant difference among the groups. Overall, the investigational vaccines were demonstrated to be safe and well tolerated in adults, and was highly effective in inducing mucosal immunities in addition to humoral and cellular immune responses defending against SARS-CoV-2 variants.Trial registration: Chictr.org identifier: ChiCTR2200063996.

Background: vaccines are complex products used in healthy populations. They should be carefully regulated, and benefits should clearly outweigh risks., Objectives: To describe the evidence used to support benefit-risk evaluations of vaccines centrally assessed by the European Medicines Agency (EMA), and to identify if real-world data (RWD) was used throughout the vaccine life cycle., Methods: Cohort study of vaccines approved in the European Union. Inclusion criteria comprised having ATC code J07 and being centrally approved between 2012 and 2022. We collected data from regulatory documents, study protocols, and, when necessary, from scientific publications. Vaccines were followed from initial approval up to March 2023., Results: We included 31 vaccines addressing 17 therapeutic areas. More than 390 studies were used in the process of initial marketing authorisation (MA) and monitoring, and 174 studies were listed in initial risk management plans. We also identified 93 studies in the EU PAS register. At MA, all vaccines had at least one pivotal trial and 27 vaccines had at least one supportive study. Most pivotal trials were randomized, double-blinded and active-controlled, with immunogenicity endpoints as primary outcome. RWD was used for extension of indications and monitoring of at least 4 vaccines, and the undertaking of RWE studies was foreseen in the RMP of at least 17 vaccines., Discussion: Our study revealed an important reliance on randomized controlled trials with individual-level randomization, and a significant focus on immunogenicity endpoints. The use of RWD in vaccine assessments so far has been restricted to COVID-19, and despite its challenges and limitations, we believe that efforts to expand adoption of RWE in continuous benefit-risk assessments should be made. We further highlight the need to enhance data transparency and reporting standards since heterogeneity among regulatory documents made it difficult to identify all the studies considered in vaccine evaluations., Competing Interests: Declaration of competing interest CEH is employed by the Copenhagen Centre for Regulatory Sciences (CORS), Department of Pharmacy, University of Copenhagen. CORS is a cross-faculty university-anchored institution involving various public (the Danish Medicines Agency, Copenhagen University) and private stakeholders (Novo Nordisk, Lundbeck, Ferring Pharmaceuticals, LEO Pharma) as well as patient organizations (Rare Diseases Denmark). The centre is purely devoted to the scientific aspects of the regulatory field and has a patient-oriented focus, and the research is not a company-specific product or directly company related. In the last three years, CORS and CEH have received funding from Novo Nordisk for projects not related to this study. LFW is a PhD student at CORS and his PhD fellowship is funded by a grant to CORS from Novo Nordisk A/S. However, the company was not involved in any aspect of the described work. DDG is also a PhD student at CORS, and she declares no competing interests. The authors declare no other known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: The emergence of nanotechnology has injected new vigor into vaccine research. Nanovaccine research has witnessed exponential growth in recent years; yet, a comprehensive analysis of related publications has been notably absent., Objective: This study utilizes bibliometric methodologies to reveal the evolution of themes and the distribution of nanovaccine research., Methods: Using tools such as VOSviewer, CiteSpace, Scimago Graphica, Pajek, R-bibliometrix, and R packages for the bibliometric analysis and visualization of literature retrieved from the Web of Science database., Results: Nanovaccine research commenced in 1981. The publication volume exponentially increased, notably in 2021. Leading contributors include the United States, the Chinese Academy of Sciences, the " Vaccine ", and researcher Zhao Kai. Other significant contributors comprise China, the University of California, San Diego, Veronique Preat, the Journal of Controlled Release , and the National Natural Science Foundation of China. The USA functions as a central hub for international cooperation. Financial support plays a pivotal role in driving research advancements. Key themes in highly cited articles include vaccine carrier design, cancer vaccines, nanomaterial properties, and COVID-19 vaccines. Among 7402 keywords, the principal nanocarriers include Chitosan, virus-like particles, gold nanoparticles, PLGA, and lipid nanoparticles. Nanovaccine is primarily intended to address diseases including SARS-CoV-2, cancer, influenza, and HIV. Clustering analysis of co-citation networks identifies 9 primary clusters, vividly illustrating the evolution of research themes over different periods. Co-citation bursts indicate that cancer vaccines, COVID-19 vaccines, and mRNA vaccines are pivotal areas of focus for current and future research in nanovaccines. "candidate vaccines," "protein nanoparticle," "cationic lipids," "ionizable lipids," "machine learning," "long-term storage," "personalized cancer vaccines," "neoantigens," "outer membrane vesicles," " in situ nanovaccine," and "biomimetic nanotechnologies" stand out as research interest., Conclusions: This analysis emphasizes the increasing scholarly interest in nanovaccine research and highlights pivotal recent research themes such as cancer and COVID-19 vaccines, with lipid nanoparticle-mRNA vaccines leading novel research directions., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Wu, Liu, Zhang, Luo, Wang, Qiao and Liu.)

Biomaterials are substances that can be injected, implanted, or applied to the surface of tissues in biomedical applications and have the ability to interact with biological systems to initiate therapeutic responses. Biomaterial-based vaccine delivery systems possess robust packaging capabilities, enabling sustained and localized drug release at the target site. Throughout the vaccine delivery process, they can contribute to protecting, stabilizing, and guiding the immunogen while also serving as adjuvants to enhance vaccine efficacy. In this article, we provide a comprehensive review of the contributions of biomaterials to the advancement of vaccine development. We begin by categorizing biomaterial types and properties, detailing their reprocessing strategies, and exploring several common delivery systems, such as polymeric nanoparticles, lipid nanoparticles, hydrogels, and microneedles. Additionally, we investigated how the physicochemical properties and delivery routes of biomaterials influence immune responses. Notably, we delve into the design considerations of biomaterials as vaccine adjuvants, showcasing their application in vaccine development for cancer, acquired immunodeficiency syndrome, influenza, corona virus disease 2019 (COVID-19), tuberculosis, malaria, and hepatitis B. Throughout this review, we highlight successful instances where biomaterials have enhanced vaccine efficacy and discuss the limitations and future directions of biomaterials in vaccine delivery and immunotherapy. This review aims to offer researchers a comprehensive understanding of the application of biomaterials in vaccine development and stimulate further progress in related fields., (© 2024. The Author(s).)

Expanding flexible vaccine manufacturing capacity (FVMC) for routine vaccines could facilitate more timely access to novel vaccines during future pandemics. Vaccine manufacturing capacity is 'flexible' if it is built on a technology platform that allows rapid adaption to new infectious agents. The added value of routine vaccines produced using a flexible platform for pandemic preparedness is not currently recognised in conventional health technology assessment (HTA) methods. We start by examining the current state of play of incentives for FVMC and exploring the relation between flexible and spare capacity. We then establish the key factors for estimating FVMC and draw from established frameworks to identify relevant value drivers. The role of FVMC as a countermeasure against pandemic risks is deemed an additional value attribute that should be recognised. Next, we address the gap in the vaccine-valuation literature between the conceptual understanding of the value of additional FVMC and the availability of accurate and reliable tools for its estimation to facilitate integration into HTA. Three practical approaches for estimating the value of additional FVMC are discussed: stated and revealed preference studies, macroeconomic modelling, and benefit-cost analysis. Lastly, we review how value recognition of additional FVMC can be realised within the HTA process for routine vaccines manufactured on flexible platforms. We argue that, while the value of additional FVMC is uncertain and further research is needed to help to better estimate it, the value of increased pandemic preparedness is likely to be too large to be ignored., (© 2024. The Author(s).)

Uptake of the COVID19 vaccinations has been generally disappointing in the United States. Efforts to overcome vaccine hesitancy could be more effective if public health messaging on the topic emphasized more personal stories rather than statistics on risk reduction., (© 2024. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)

Objectives: Identifying whether a country is ready to deploy a new vaccine or improve uptake of an existing vaccine requires knowledge of a diverse range of interdependent, context-specific factors. This scoping review aims to identify common themes that emerge across articles, which include tools or guidance that can be used to establish whether a country is ready to deploy a new vaccine or increase uptake of an underutilised vaccine., Design: Scoping review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses for Scoping Reviews guidelines., Data Sources: Embase, CINAHL, Cochrane Library, Google Scholar, MEDLINE, PsycINFO and Web of Science were searched for articles published until 9 September 2023. Relevant articles were also identified through expert opinion., Eligibility Criteria: Articles published in any year or language that included tools or guidance to identify factors that influence a country's readiness to deploy a new or underutilised vaccine., Data Extraction and Synthesis: Two independent reviewers screened records and performed data extraction. Findings were synthesised by conducting a thematic analysis., Results: 38 articles met our inclusion criteria; these documents were created using methodologies including expert review panels and Delphi surveys and varied in terms of content and context-of-use. 12 common themes were identified relevant to a country's readiness to deploy a new or underutilised vaccine. These themes were as follows: (1) legal, political and professional consensus; (2) sociocultural factors and communication; (3) policy, guidelines and regulations; (4) financing; (5) vaccine characteristics and supply logistics; (6) programme planning; (7) programme monitoring and evaluation; (8) sustainable and integrated healthcare provision; (9) safety surveillance and reporting; (10) disease burden and characteristics; (11) vaccination equity and (12) human resources and training of professionals., Conclusions: This information has the potential to form the basis of a globally applicable evidence-based vaccine readiness assessment tool that can inform policy and immunisation programme decision-makers., Competing Interests: Competing interests: LH, AE, AL, RM and AlB are employees of Merck Sharp & Dohme LLC, a subsidiary of Merck & Co., Inc., Rahway, NJ, USA and potentially own stock and/or hold stock options in Merck & Co., Inc., Rahway, NJ, USA., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

The European Union (EU) regulatory network was at the forefront of the safety monitoring of COVID-19 vaccines during the pandemic. An unprecedented number of case reports of suspected adverse reactions after vaccination called for huge efforts for the assessment of this safety information, to ensure that any possible risks were detected and managed as early as possible, while ruling out coincidental but temporally related adverse health outcomes. We describe the role of the European Medicines Agency alongside the EU regulatory network in the safety monitoring of the COVID-19 vaccines, and provide an insight into challenges, particularities and outcomes of the scientific assessment and regulatory decisions in the complex, dynamic international environment of the pandemic. We discuss the flexible procedural tools that were used to ensure an expedited scientific assessment of safety issues, and subsequent updates of the product information (i.e., labelling) when available evidence (e.g., spontaneous reports, findings from observational studies and/or scientific literature) suggested that causal association is at least a reasonable possibility. The safety monitoring was accompanied by enhanced transparency measures, proactive communication, and easy access to information, which played a key role in public reassurance. The pandemic has been a powerful booster for worldwide collaboration, exchange of information and work-sharing. The safety monitoring of COVID-19 vaccines continues, and the lessons learned will be applied in future safety reviews, as well as future health emergencies., (© 2024. The Author(s).)

Introduction: Since the start of the COVID-19 pandemic, data published on the immunogenicity of the SARS-CoV-2 BNT 162B2 vaccine in pediatric patients receiving renal replacement therapy are scant. Our primary objective is to study this population's humoral immune response to the COVID-19 vaccine., Methods: Pediatric kidney transplant recipients (PKTRs) and hemodialysis recipients (HR) at our center who received two doses of the SARS-CoV-2 BNT 162B2 vaccine were included. Transplant and HR who had PCR-positive COVID-19 infections during the study, regardless of their vaccine status, were also included. SARS-CoV-2 anti-spike protein (S1/S2) IgG was measured after the second dose of the vaccine and after any PCR-positive COVID-19 infection as routine clinical practice. Data on demographics, induction, maintenance immunosuppressants, type of transplant, and posttransplant or dialysis duration were included., Results: Of the 61 patients included, 19 were dialysis recipients who received two doses of vaccine without subsequent infection (HV), and 42 were kidney transplant recipients. All dialysis patients and 33 (78.6%) transplant recipients received two doses of the SARS-CoV-2 BNT 162b2 vaccine. A total of 33.3% (11/33) of the transplant recipients who received vaccination developed COVID-19 infection (KTH) at a median time of 13 days after the second dose of vaccine. Nine transplant patients had pure COVID-19 infection without vaccination (KTI). The seroconversion rate in the HV group was 94.7% (18/19) compared to 50% (11/22) in the kidney transplant vaccine recipients who did not develop subsequent COVID-19 infection (KTV) (p < .001). The median S1/S2 IgG titers for the HV group were 400 AU/mL versus 15 AU/mL in the KTV group (p < .0001). There was no significant difference in the duration of the test from the second dose of the vaccine between HV and KTV (55 vs. 33.5 days, p = .095). The KTH had higher titers than KTV group (370 vs. 15 p < .0001). The median duration of the test after vaccination in the vaccine group and those with hybrid immunity was similar (35 vs. 33.5 days, p = .2).There were no clear predictors for seroconversion in the PKTRs. Natural infection alone was as good as the vaccine in eliciting humoral immune response., Conclusion: The humoral immune response to two doses of the SARS-CoV-2 BNT 162B2 vaccine in PKTRs without subsequent COVID-19 infection is suboptimal compared to that in hemodialysis recipients and in PKTRs with hybrid immunity from both infection and vaccination., (© 2024 Wiley Periodicals LLC.)

Objectives: The COVID-19 pandemic required rapid development of vaccines within a short period of time which did not allow to assess vaccine effectiveness (VE) in the long-term., Methods: A computerized literature search was undertaken to identify eligible studies, with no language restrictions, published between 1 December 2020 and 30 June 2023., Results: Out of a total of 27,597 publications, 761 studies were included. Early VE of 87.2% decreased to 55.1% after 9 months among populations fully immunized not only with mRNA (proxy mRNA) vaccines, and 66.3% decreased to 23.5% in populations immunized exclusively with non-mRNA vaccines. Protection against severe COVID-19 declined to 80.9% for proxy mRNA vaccines and 67.2% for non-mRNA vaccines. Omicron variants significantly diminished VE. Within 6-8 months of receiving a single booster of an mRNA vaccine, VE declined to 14.0% and 67.7% for any and severe COVID-19, respectively. Multiple mRNA booster doses restored protection that declined to 29.5% and 70.6% for any and severe COVID-19, respectively, within 5-7 months., Conclusion: Outcomes of this meta-regression underscore the evolving nature of COVID-19 in response to vaccination, dosing schedules, and emerging variants, and provide crucial insights for public health interventions and vaccination strategies., Competing Interests: Declarations of competing interest We declare no competing interests., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: The introduction of the vaccine against SARS-CoV-2 has represented a cornerstone in the containment of the pandemic. Our aim was to assess the vaccination schedules in relation to the infection free interval and to the duration of positivity in case of infection., Study Design: This study involves the SARS-CoV-2 infected people managed by the Local Health Authority ASL 1 Abruzzo. The data collected included: vaccine administration date, vaccine type, information on the Polymerase Chain Reaction test positivity, and demographic variables, such as age and sex., Methods: The duration of Polymerase Chain Reaction test positivity was assessed in relation to the vaccination status, the vaccine type and the time interval between the last vaccination dose and the first nasopharyngeal positive swab over the considered period., Results: The infection duration (DAYS) was significantly shorter in subjects vaccinated with a booster dose than unvaccinated subjects (12.8 vs 14.6; p<0.0001) and subjects vaccinated with the primary series only (12.8 vs 14.1; p<0.0001). Duration of PCR positivity was shorter with heterologous immunisation than with other vaccination schedules (p=0.0317)., Conclusions: This study highlights, in a large cohort of patients, the association between vaccination schedule and the response to infection.

Objectives: The InVITE study, starting in August 2021, was designed to examine the immunogenicity of different vaccine regimens in several countries including the Democratic Republic of Congo, Guinea, Liberia, and Mali. Prevaccination baseline samples were used to obtain estimates of previous SARS-CoV-2 infection in the study population., Methods: Adult participants were enrolled upon receipt of their initial COVID-19 vaccine from August 2021 to June 2022. Demographic and comorbidity data were collected at the time of baseline sample collection. SARS-CoV-2 serum anti-Spike and anti-Nucleocapsid antibody levels were measured., Results: Samples tested included 1016, 375, 663, and 776, from DRC, Guinea, Liberia, and Mali, respectively. Only 0.8% of participants reported a prior positive SARS-CoV-2 test, while 83% and 68% had anti-Spike and anti-Nucleocapsid antibodies, respectively., Conclusions: Overall SARS-CoV-2 seroprevalence was 86% over the accrual period, suggesting a high prevalence of SARS-CoV-2 infection. Low rates of prior positive test results may be explained by asymptomatic infections, limited access to SARS-CoV-2 test kits and health care, and inadequate surveillance. These seroprevalence rates are from a convenience sample and may not be representative of the population in general, underscoring the need for timely, well-conducted surveillance as part of global pandemic preparedness., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Background: The trajectories of all-cause deaths linked to omicron infections are rarely studied, especially in relation to the efficacy of booster shots. For assessing three epidemiological death trajectories, including dying from COVID-19, dying with COVID-19, and non-COVID-19 death, we offer a new COVID-19-and-death competing risk model that deals with the primary pathway (e.g., dying from COVID-19) competing with two other pathways., Methods: We applied this model to track three trajectories: deaths directly from COVID-19, deaths with COVID-19 as a contributing factor, and indirect non-COVID-19 deaths. The study used data from a Taiwanese cohort, covering periods of Omicron subvariants BA.2, BA.5, and BA.2.75. It focused on the effectiveness of monovalent and bivalent booster vaccines against these death trajectories., Results: The highest mortality was observed during the BA.2 phase, which decreased in the BA.5 period and increased again in the BA.2.75 period. Analyzing each trajectory, we noted similar trends in deaths directly from and with COVID-19, while non-COVID-19 deaths remained stable across subvariants. Booster vaccines reduced all-cause mortality by 58% (52%-62%) for BA.2, 70% (65%-75%) for BA.5%, and 75% (70%-80%) for BA.2.75, compared to incomplete vaccination. The reduction in deaths directly from COVID-19 was 66% (61%-72%) for BA.2, 78% (72%-84%) for BA.5%, and 85% (76%-93%) for BA.2.75. For deaths with COVID-19, the figures were 46% (36%-55%), 76% (68%-84%), and 90% (86%-95%). Additionally, the booster shots decreased non-COVID-19 deaths by 64% (63%-66%) for BA.2, 38% (36%-40%) for BA.5, and 19% (17%-21%) for BA.2.75., Conclusion: Our competing risk analysis is effective for monitoring all-cause death trajectories amidst various Omicron infections. It provides insights into the impact of booster vaccines, especially bivalent ones, and highlights the consequences of inadequate healthcare for vulnerable groups., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Introduction: The aim of this study was to assess the possible extent of bias due to violation of a core assumption (event-dependent exposures) when using self-controlled designs to analyse the association between COVID-19 vaccines and myocarditis., Methods: We used data from five European databases (Spain: BIFAP, FISABIO VID, and SIDIAP; Italy: ARS-Tuscany; England: CPRD Aurum) converted to the ConcePTION Common Data Model. Individuals who experienced both myocarditis and were vaccinated against COVID-19 between 1 September 2020 and the end of data availability in each country were included. We compared a self-controlled risk interval study (SCRI) using a pre-vaccination control window, an SCRI using a post-vaccination control window, a standard SCCS and an extension of the SCCS designed to handle violations of the assumption of event-dependent exposures., Results: We included 1,757 cases of myocarditis. For analyses of the first dose of the Pfizer vaccine, to which all databases contributed information, we found results consistent with a null effect in both of the SCRI and extended SCCS, but some indication of a harmful effect in a standard SCCS. For the second dose, we found evidence of a harmful association for all study designs, with relatively similar effect sizes (SCRI pre = 1.99, 1.40 - 2.82; SCRI post 2.13, 95 %CI - 1.43, 3.18; standard SCCS 1.79, 95 %CI 1.31 - 2.44, extended SCCS 1.52, 95 %CI = 1.08 - 2.15). Adjustment for calendar time did not change these conclusions. Findings using all designs were also consistent with a harmful effect following a second dose of the Moderna vaccine., Conclusions: In the context of the known association between COVID-19 vaccines and myocarditis, we have demonstrated that two forms of SCRI and two forms of SCCS led to largely comparable results, possibly because of limited violation of the assumption of event-dependent exposures., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: University Medical Center Utrecht in collaboration with the Vaccine Monitoring Collaboration for Europe network (VAC4EU). reports financial support was provided by European Medicines Agency. Anna Schultze reports a relationship with GSK that includes: funding grants. Ian Douglas reports a relationship with GSK that includes: equity or stocks and funding grants. Fabio Riefolo reports a relationship with TEAMIT Institute, a research management organisation that participates in financially supported studies for the European Medicines Agency and related healthcare authorities, pharmaceutical companies, and the European Union that includes: employment. Felipe Villalobos, Meritxell Palleja-Millan, Carlo Alberto Bissacco and Elena Segundo reports a relationship with IDIAPJGol, which receives institutional research funding from public and private partners, pharmaceutical companies and regulatory agencies that includes: employment. Miriam Sturkenboom reports a relationship with University Medical Center Utrecht, which conducts studies for the European Medicines Agency, the European Commission and medicine manufacturers, all according to the ENCePP code of conduct that includes: employment. Carlos E. Duran reports a relationship with University Medical Center Utrecht, which receives institutional research funding from pharmaceutical companies and regulatory agencies that includes: employment. Rosa Gini and Davide Messina reports a relationship with ARS Tuscany, which reports funding from the Innovative Medicines Initiative, RTI, PHARMO, University of Southern Denmark, University of Utrecht, Eli Lilly, Pfizer, Novartis, AstraZeneca, Galapagos, and LeoPharma that includes: employment. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier India Pvt Ltd. All rights reserved.)

Background: Despite vaccines' effectiveness in reducing COVID-19 infection rates and disease severity, their impact on critical patients presenting with acute respiratory failure is elusive. The aim of this study was to further investigate the influence of vaccination on mortality rates among severely ill COVID-19 patients experiencing acute respiratory failure., Methods: This retrospective cohort study was carried out at a tertiary medical center in Taiwan. From April to September 2022, patients who tested positive for the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) through reverse transcription polymerase chain reaction (RT-PCR) and subsequently experienced acute respiratory failure were included in the study. Baseline characteristics, including vaccination history, along with information regarding critical illness and clinical outcomes, were gathered and compared between patients who received the vaccine and those who did not., Results: A total of 215 patients with COVID-19 exhibiting acute respiratory failure, as confirmed via RT‒PCR, were included in the analysis. Of this cohort, sixty-six (30.7%) patients died within 28 days. Neither administration of the vaccine nor achievement of primary series vaccination status had a significantly different effect on 28 day mortality, number of viral shedding events, acute respiratory distress syndrome (ARDS) incidence or other clinical outcomes. Patients who received the booster vaccine and completed the primary series showed a tendency of increased 28 days of ventilator-free status, though this difference was not statistically significant (p = 0.815)., Conclusions: Vaccination status did not significantly influence mortality rates, the occurrence of ARDS, or the viral shedding duration in COVID-19 patients with acute respiratory failure., (© 2024. The Author(s).)

Behavioural science constructs can be incorporated into messaging strategies to enhance the effectiveness of public health campaigns by increasing the occurrence of desired behaviours. This study investigated the impact of behavioural science-informed text message strategies on COVID-19 vaccination rates in 18-39-year-olds in an area of low uptake in London during the first vaccination offer round in the United Kingdom. This three-armed randomised trial recruited unvaccinated residents of an urban Central London suburb being offered their first vaccination between May and June 2021. Participants were randomised to receive the control (current practice) text message or one of two different behavioural science-informed COVID-19 vaccine invitation strategies. Both intervention strategies contained the phrase "your vaccine is ready and waiting for you", aiming to evoke a sense of ownership, with one strategy also including a pre-alert message. The main outcome measures were vaccination rates at 3 and 8 weeks after message delivery. A total of 88,820 residents were randomly assigned to one of the three trial arms. Each arm had a vaccine uptake rate of 27.2 %, 27.4 % and 27.3 % respectively. The mean age of participants was 28.2 years (SD ± 5.7), the mean index of multiple deprivation was 4.3 (SD ± 2.0) and 50.4 % were women. Vaccine uptake varied by demographics, however there was no significant difference between trial arms (p = 0.872). Delivery was successful for 53.6 % of text messages. Our choice of behavioural science informed messaging strategies did not improve vaccination rates above the rate seen for the current practice message. This likely reflects the wide exposure to public health campaigns during the pandemic, as such text messages nudges were unlikely to alter existing informed decision-making processes. Text message delivery was relatively low, indicating a need for accurate mobile phone number records and multi-modal approaches to reach eligible patients for vaccination. The protocol was registered at clinicaltrials.gov (NCT04895683) on 20/05/2021., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Solid cancer patients are at higher risk of SARS-CoV-2 infection and severe complications. Moreover, vaccine-induced antibody response is impaired in patients on anticancer treatment. In this retrospective, observational, hypothesis-generating, cohort study, we assessed the antibody response to the third dose of mRNA vaccine in a convenience sample of patients on anticancer treatment, comparing it to that of the primary two-dose cycle. Among 99 patients included, 62.6% were ≥60 years old, 32.3% males, 67.7% with advanced disease. Exactly 40.4% were receiving biological therapy, 16.2% chemotherapy only and 7.1% both treatments. After the third dose, seroconversion rate seems to increase significantly, especially in non-responders to two doses. Heterologous vaccine-type regimen (two-dose mRNA-1273 and subsequent tozinameran or vice versa) results in higher antibody levels. This explorative study suggests that repeated doses of mRNA-vaccines could be associated with a better antibody response in this population. Furthermore, heterologous vaccine-type three-dose vaccination seems more effective in this population. Since this is a hypothesis-generating study, adequately statistically powered studies should validate these results., (© 2023 The Authors. International Journal of Cancer published by John Wiley & Sons Ltd on behalf of UICC.)

Background: Facing a surge of COVID-19 cases in late August 2021, the U.S. state of Illinois re-enacted its COVID-19 mask mandate for the general public and issued a requirement for workers in certain professions to be vaccinated against COVID-19 or undergo weekly testing. The mask mandate required any individual, regardless of their vaccination status, to wear a well-fitting mask in an indoor setting., Methods: We used Illinois Department of Public Health's COVID-19 confirmed case and vaccination data and investigated scenarios where masking and vaccination would have been reduced to mimic what would have happened had the mask mandate or vaccine requirement not been put in place. The study examined a range of potential reductions in masking and vaccination mimicking potential scenarios had the mask mandate or vaccine requirement not been enacted. We estimated COVID-19 cases and hospitalizations averted by changes in masking and vaccination during the period covering October 20 to December 20, 2021., Results: We find that the announcement and implementation of a mask mandate are likely to correlate with a strong protective effect at reducing COVID-19 burden and the announcement of a vaccinate-or-test requirement among frontline professionals is likely to correlate with a more modest protective effect at reducing COVID-19 burden. In our most conservative scenario, we estimated that from the period of October 20 to December 20, 2021, the mask mandate likely prevented approximately 58,000 cases and 1,175 hospitalizations, while the vaccinate-or-test requirement may have prevented at most approximately 24,000 cases and 475 hospitalizations., Conclusion: Our results indicate that mask mandates and vaccine-or-test requirements are vital in mitigating the burden of COVID-19 during surges of the virus., (© 2024. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)

Background: It is known that COVID-19 disproportionally adversely affects the immunocompromised, including kidney transplant recipients (KTR), as compared to the general population. Risk factors for adverse outcomes and vaccine seroconversion patterns are not fully understood. Australia was uniquely positioned to reduce initial case numbers during the 2021-2022 pandemic period due to its relative isolation and several significant public health interventions. South-Western Sydney Local Heath District was one of the predominant regions affected., Methods: A single centre, prospective cohort study of prevalent renal transplant recipients was conducted between 25th July 2021 and 1st May 2022. Baseline characteristics, COVID-19 vaccination status, COVID-19 diagnosis and outcomes were determined from the electronic medical record, Australian vaccination register and Australian and New Zealand Dialysis and Transplant Registry. Assessment of vaccine-induced seroconversion was assessed with ELISA in a subpopulation. Analysis was performed using SPSS v.28., Results: We identified 444 prevalent transplant recipients (60% male, 50% diabetic, median age 58 years (Interquartile range (IQR)21.0) and eGFR 56 ml/min/1.73m 2 (IQR 21.9). COVID-19 was identified in 32% (n = 142) of patients, of which 38% (n = 54) required hospitalisation and 7% (n = 10) died. At least one COVID-19 vaccination was received by 95% (n = 423) with 17 (4%) patients remaining unvaccinated throughout the study period. Seroconversion after 2 and 3 doses of vaccine was 22% and 48% respectively. Increased COVID-19 related deaths were associated with older age (aOR 1.1, 95% CI 1.004-1.192, p = 0.040), smoking exposure (aOR 8.2, 05% CI 1.020-65.649, p = 0.048) and respiratory disease (aOR 14.2, 95%CI:1.825-110.930, p = 0.011) on multi-variable regression analysis. Receipt of three doses of vaccination was protective against acquiring COVID-19 (aOR 0.48, 95% CI 0.287-0.796, p = 0.005) and death (aOR 0.6, 95% CI: 0.007-0.523, p = 0.011), but not against hospitalisation (p = 0.32). Seroconversion was protective for acquiring COVID-19 on multi-variable regression independent of vaccination dose (aOR 0.1, 95%CI: 0.0025-0.523, p = 0.011)., Conclusions: COVID-19 was associated with a high mortality rate. Older age, respiratory disease and prior smoking exposure may be risk factors for increased mortality. Vaccination of 3 doses is protective against acquiring COVID-19 and death, however not hospitalisation. Antibody response is protective for acquiring COVID-19, however seroconversion rates are low., (© 2024. The Author(s).)

Background: Vaccination has been recommended as one of the approaches for the control of COVID-19 pandemic. However, adequate vaccine coverage is critical to the effectiveness of the vaccine at population level. Data on acceptability of the vaccine in Ugandan urban areas are limited. This study examined the prevalence, factors associated with willingness to accept COVID-19 vaccine including reasons for not taking COVID-19 vaccine in a predominantly urban population of Wakiso, central Uganda., Methods: Data were obtained from a cross-sectional study conducted between March 1st, 2021 and September 30th, 2021 in the urban population-based cohort of the Africa Medical and behavioral Sciences Organization (AMBSO). A Multivariable modified Poisson regression analysis was used to estimate adjusted prevalence ratios (aPR) and 95% confidence intervals of willingness to accept the COVID-19 vaccine., Results: A total of 1,903 participants were enrolled in this study; 61% of whom were females. About 63% of participants indicated their willingness to accept the COVID-19 vaccine. Persons aged 13-19 years (aPR = 0.79; [95% CI: 0.74, 0.84]) or 20-29years (aPR = 0.93; [95% CI: 0.88, 0.98]) were less likely to accept the vaccine compared to persons aged 40-49 years. Persons with post-primary level of education (aPR = 1.05; [95% CI: 1.02, 1.09]) were more likely to accept the vaccine compared to persons with primary level of education. Additionally, students or individuals working in government (aPR = 1.13; [95% CI: 1.04, 1.23]) were more likely to accept the vaccine compared to individuals doing construction and Mechanic work as their main occupation. Reported reasons for not taking a COVID-19 vaccine included; concerns about side effects of the vaccine 154(57.0%), 64(23.7%) did not think the vaccines were effective, while 32(11.9%) did not like the vaccines., Conclusion: A substantial proportion of individuals were not willing to accept the COVID-19 vaccine. Health education campaigns on vaccination within urban communities could help reduce COVID-19 vaccine misconceptions in the urban populations more especially the young and persons with low levels of formal education., (© 2024. The Author(s).)

In a health emergency, governments rely on public trust in their policy, and anticipate its compliance to protect health and save lives. Vaccine hesitancy compromises this process when an emergency involves infections. The prevailing discourse on vaccine hesitancy often describes it as a static phenomenon, ignoring its expanse and complexity, and neglecting the exploration of tools to address it. This article diverges from the conventional perspective by explaining the case of Pakistan and its communication strategy for the COVID-19 vaccine. Decades of polio vaccine hesitancy, rooted in the country's fight against terrorism, constitute its history. On the other hand, the first-ever launch of typhoid conjugate vaccine involving 35 million kids during 2019-2021 was a success. Against this backdrop, the country considered vaccine hesitancy as a dynamic phenomenon, interwoven with the social ecology and the responsiveness of the healthcare system. Its communication strategy facilitated those willing to receive the vaccine, while being responsive to the information needs of those still in the decision-making process. In the face of both hesitancy and a scarcity of vaccine doses, the country successfully inoculated nearly 70% (160 million) of its population in just over 1 year. People's perceptions about the COVID-19 vaccine also improved over time. This achievement offers valuable insights and tools for policymakers and strategists focused on the demand side of vaccine programmes. The lessons can significantly contribute to the global discourse on improving vaccine confidence and bolstering global health security., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Objectives: To assess incidence, severity and predictors of COVID-19, including protective post-vaccination levels of antibodies to the receptor-binding domain of SARS-CoV-2 spike protein (anti-RBD), informing further vaccine strategies for patients with immune-mediated inflammatory diseases (IMIDs) on immunosuppressive medication., Methods: IMIDs on immunosuppressives and healthy controls (HC) receiving SARS-CoV-2 vaccines were included in this prospective observational study. COVID-19 and outcome were registered and anti-RBD antibodies measured 2-5 weeks post-immunisation., Results: Between 15 February 2021 and 15 February 2023, 1729 IMIDs and 350 HC provided blood samples and self-reported COVID-19. The incidence of COVID-19 was 66% in patients and 67% in HC, with re-infection occurring in 12% of patients. Severe COVID-19 was recorded in 22 (2%) patients and no HC. No COVID-19-related deaths occurred. Vaccine-induced immunity gave higher risk of COVID-19 (HR 5.89 (95% CI 4.45 to 7.80)) than hybrid immunity. Post-immunisation anti-RBD levels <6000 binding antibody units/mL were associated with an increased risk of COVID-19 following three (HR 1.37 (95% CI 1.08 to 1.74)) and four doses (HR 1.28 (95% CI 1.02 to 1.62)), and of COVID-19 re-infection (HR 4.47 (95% CI 1.87 to 10.67))., Conclusion: Vaccinated patients with IMID have a low risk of severe COVID-19. Hybrid immunity lowers the risk of infection. High post-immunisation anti-RBD levels protect against COVID-19. These results suggest that knowledge on COVID-19 history, and assessment of antibody levels post-immunisation can help individualise vaccination programme series in high-risk individuals., Trial Registration Number: NCT04798625., Competing Interests: Competing interests: KHB reports funding from Akershus University Hospital and speakers bureau for Janssen-Cilag. TKK reports grants from AbbVie, Amgen, Bristol-Myers Squibb, Merck Sharp & Dohme, Novartis, Pfizer, Union Chimique Belge; consulting fees from AbbVie, Biogen, Celltrion, Eli Lilly, Gilead, Mylan, Novartis, Pfizer, Sandoz, Sanofi and speakers bureau from Amgen, Celltrion, Egis, Evapharma, Ewopharma, Hikma, Oktal, Sandoz and Sanofi. GG reports speakers bureau from Pfizer, Bayer, Sanofi, Thermo Fisher, GSK and Vitusapotek, and participation on advisory board for Moderna, AstraZeneca, Janssen and Seqirus. JJ reports grants from Boehringer Ingelheim; speakers bureau from AbbVie, Bristol-Myers Squibb, Galapagos, Gilead, Janssen, Pfizer, Roche, Sandoz and Takeda; and participation on advisory board for AbbVie, Bristol-Myers Squibb, Galapagos, Gilead, Janssen, Lilly, Pfizer, Roche, Sandoz and Takeda. EAH reports consultant fees from AbbVie, Boehringer Ingelheim, Eli Lilly and Gilead; and speakers bureau from Pfizer and UCB. LAM reports funding from KG Jebsen foundation, support for infrastructure and biobanking from the University of Oslo and Oslo University Hospital, grants from the Coalition of Epidemic Preparedness Innovations and speakers bureau from Novartis, and Cellgene. JTV reports grants from the Coalition of Epidemic Preparedness Innovations. GLG reports funding from the South-Eastern Norway Regional Health Authority, The Coalition for Epidemic Preparedness Innovations, RCN Covid (312693), a KG Jebsen Foundation (grant 19), Dr Trygve Gythfeldt og frues forskningsfond, Karen Fossum Foundation, the Research Foundation at Diakonhjemmet Hospital and Oslo University Hospital; speakers bureau from AbbVie, Galapagos, Pfizer and Union Chimique Belge; and participation on advisory board of AbbVie, Galapagos, Pfizer and Union Chimique Belge. KKJ reports speakers bureau from Bristol-Myers Squibb and Roche. SWS reported participation on advisory board AstraZeneca. All other authors declare no competing interests., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

National vaccine injury compensation serves as a crucial and significant safety net for individuals affected by government-recommended vaccines during a pandemic, contributing to the community's overall safety. In the Republic of Korea, compensation for adverse events resulting from coronavirus disease 2019 (COVID-19) vaccinations has been provided through the National Vaccine Injury Compensation Program introduced in 1995. However, there have been limitations with these measures during the COVID-19 pandemic owing to strict criteria for substantiating causality between the vaccine and injury, its nontransparent process of determining whether to compensate, and the compensation amount that is not practically calculated. This article reviewed the Vaccine Injury Compensation Programs in 10 major countries to present implications for improving the Korean system. Expanding the scope of national accountability is essential to compensate for the consequences of adhering to national policies during public health crises. Therefore, valuable insight can be obtained from examining the systems in Germany, Japan, and Taiwan, which have implemented more relaxed criteria for determining causality in compensation cases; Thailand's system, which provides the mandatory payment of preliminary compensation for damage caused by vaccination; systems in Germany, France, and Japan, which offer compensation for vaccine injuries from a practical perspective; and systems in France and the United Kingdom, which have a process allowing the assessment records to be shared with the claimants. Furthermore, a dedicated agency for vaccine injury compensation, as seen in France, the United Kingdom, and Australia, is necessary to enhance the efficiency of the Korean system., Competing Interests: The authors have no potential conflicts of interest to disclose., (© 2024 The Korean Academy of Medical Sciences.)

Introduction: Following the coronavirus disease 19 (COVID-19), caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection, vaccination became the main strategy against disease severity and even death. Healthcare workers were considered high-risk for infection and, thus, were prioritised for vaccination., Methods: A follow-up to a SARS-CoV-2 seroprevalence study among clinical and non-clinical HCWs at the Aga Khan University Hospital, Nairobi, we assessed how vaccination influenced SARS-CoV-2 anti-spike IgG antibody responses and kinetics. Blood samples were drawn at two points spanning 6 to 18 months post-vaccination, and SARS-CoV-2 spike antibody levels were determined by enzyme-linked immunosorbent assay., Results: Almost all participants, 98% (961/981), received a second vaccine dose, and only 8.5% (83/981) received a third dose. SARS-CoV-2 spike IgG antibodies were detected in 100% (961/961) and 92.7% (707/762) of participants who received two vaccine doses, with the first and second post-vaccine test, respectively, and in 100% (83/83) and 91.4% (64/70) of those who received three vaccine doses at the first and second post-vaccine test, respectively. Seventy-six participants developed mild infections, not requiring hospitalisation even after receiving primary vaccination. Receiving three vaccine doses influenced the anti-spike S/Co at both the first (p<0.001) and second post-vaccination testing (p<0.001). Of those who tested SARS-CoV-2 positive, the anti-spike S/Co ratio was significantly higher than those who were seronegative at the first post-vaccine test (p = 0.001). Side effects were reported by almost half of those who received the first dose, 47.3% (464/981), 28.9% (278/961) and 25.3% (21/83) of those who received the second and third vaccine doses, respectively., Discussion and Conclusion: Following the second dose of primary vaccination, all participants had detectable anti-spike antibodies. The observed mild breakthrough infections may have been due to emerging SARS-CoV-2 variants. Findings suggest that although protective antibodies are induced, vaccination protected against COVID-19 disease severity and not necessarily infection., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Mwangi et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: We previously demonstrated that when vaccines prevent infection, the dynamics of mixing between vaccinated and unvaccinated sub-populations is such that use of imperfect vaccines markedly decreases risk for vaccinated people, and for the population overall. Risks to vaccinated people accrue disproportionately from contact with unvaccinated people. In the context of the emergence of Omicron SARS-CoV-2 and evolving understanding of SARS-CoV-2 epidemiology, we updated our analysis to evaluate whether our earlier conclusions remained valid., Methods: We modified a previously published Susceptible-Infectious-Recovered (SIR) compartmental model of SARS-CoV-2 with two connected sub-populations: vaccinated and unvaccinated, with non-random mixing between groups. Our expanded model incorporates diminished vaccine efficacy for preventing infection with the emergence of Omicron SARS-CoV-2 variants, waning immunity, the impact of prior immune experience on infectivity, "hybrid" effects of infection in previously vaccinated individuals, and booster vaccination. We evaluated the dynamics of an epidemic within each subgroup and in the overall population over a 10-year time horizon., Results: Even with vaccine efficacy as low as 20%, and in the presence of waning immunity, the incidence of COVID-19 in the vaccinated subpopulation was lower than that among the unvaccinated population across the full 10-year time horizon. The cumulative risk of infection was 3-4 fold higher among unvaccinated people than among vaccinated people, and unvaccinated people contributed to infection risk among vaccinated individuals at twice the rate that would have been expected based on the frequency of contacts. These findings were robust across a range of assumptions around the rate of waning immunity, the impact of "hybrid immunity", frequency of boosting, and the impact of prior infection on infectivity in unvaccinated people., Interpretation: Although the emergence of the Omicron variants of SARS-CoV-2 has diminished the protective effects of vaccination against infection with SARS-CoV-2, updating our earlier model to incorporate loss of immunity, diminished vaccine efficacy and a longer time horizon, does not qualitatively change our earlier conclusions. Vaccination against SARS-CoV-2 continues to diminish the risk of infection among vaccinated people and in the population as a whole. By contrast, the risk of infection among vaccinated people accrues disproportionately from contact with unvaccinated people., (Copyright: © 2024 Fisman et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: Pregnant persons are at increased risk of severe COVID-19 illness. Bivalent mRNA COVID-19 vaccination is recommended for everyone, including pregnant persons. However, data are limited on the safety of bivalent mRNA COVID-19 vaccination during pregnancy., Objective: To evaluate and summarize reports to the Vaccine Adverse Event Reporting System (VAERS), a national spontaneous reporting system, among pregnant persons who received bivalent mRNA COVID-19 vaccine., Methods: VAERS U.S. reports of adverse events (AEs) in pregnant persons who received the bivalent mRNA COVID-19 vaccine from 9/1/2022-03/31/2023 were identified. Clinicians reviewed all reports and available medical records. AEs of these reports were compared with AEs reported to VAERS following monovalent mRNA COVID-19 booster vaccination in pregnancy., Results: VAERS received 136 reports for pregnant persons who received bivalent mRNA COVID-19 vaccine; 87 (64 %) after BNT162b2 (Pfizer-BioNTech), and 48 (35 %) after mRNA-1273 (Moderna); 28 (20.6 %) reports were classified as serious. The most common pregnancy-specific outcomes reported included 12 (8.8 %) spontaneous abortions (<20 weeks gestation), 6 (4.4 %) episodes of preterm delivery, and 5 (3.7 %) reports of preeclampsia. One stillbirth (≥20 weeks gestation) was reported. No maternal or infant deaths were reported. There were 6 reports of AEs in infants, which included 3 reports of admissions to the neonatal intensive care unit: two infants with low birth weight, and one infant with a patent ductus arteriosus and patent foramen ovale. Non-pregnancy-specific adverse events were mostly COVID-19 infection and systemic reactions (e.g., headache, fatigue). Pregnancy-specific conditions were reported less frequently after bivalent mRNA COVID-19 vaccination compared to monovalent mRNA COVID-19 booster vaccination (3rd and 4th dose)., Conclusions: Based on this review of reports to VAERS, the safety profile of bivalent mRNA COVID-19 vaccination in pregnant persons was comparable to that observed for monovalent mRNA COVID-19 booster vaccination (3rd and 4th dose) in pregnant persons., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Published by Elsevier Ltd.)

Adenovirus vaccines, particularly the COVID-19 Ad5-nCoV adenovirus vaccine, have emerged as promising tools in the fight against infectious diseases. In this study, we investigated the structure of the T cell response to the Spike protein of the SARS-CoV-2 virus used in the COVID-19 Ad5-nCoV adenoviral vaccine in a phase 3 clinical trial (NCT04540419). In 69 participants, we collected peripheral blood samples at four time points after vaccination or placebo injection. Sequencing of T cell receptor repertoires from Spike-stimulated T cell cultures at day 14 from 17 vaccinated revealed a more diverse CD4 + T cell repertoire compared to CD8 + . Nevertheless, CD8 + clonotypes accounted for more than half of the Spike-specific repertoire. Our longitudinal analysis showed a peak T cell response at day 14, followed by a decline until month 6. Remarkably, multiple T cell clonotypes persisted for at least 6 months after vaccination, as demonstrated by ex vivo stimulation. Examination of CDR3 regions revealed homologous sequences in both CD4 + and CD8 + clonotypes, with major CD8 + clonotypes sharing high similarity with annotated sequences specific for the NYNYLYRLF peptide, suggesting potential immunodominance. In conclusion, our study demonstrates the immunogenicity of the Ad5-nCoV adenoviral vaccine and highlights its ability to induce robust and durable T cell responses. These findings provide valuable insight into the efficacy of the vaccine against COVID-19 and provide critical information for ongoing efforts to control infectious diseases., Competing Interests: VD and AA are employees of the NPO Petrovax Pharm LLC and were involved in the interpretation of the results of the phase 3 clinical trial of the Ad5-nCoV adenoviral vaccine NCT04540419. They participated in the organization of the clinical trial of vaccine efficacy, providing blood samples at the specified time points. They were informed about the results of the work, but did not participate in the interpretation of the obtained data, did not make decisions about the course of the experiments. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Sheetikov, Khmelevskaya, Zornikova, Zvyagin, Shomuradova, Serdyuk, Shakirova, Peshkova, Titov, Romaniuk, Shagina, Chudakov, Kiryukhin, Shcherbakova, Khamaganova, Dzutseva, Afanasiev, Bogolyubova and Efimov.)

Acute Disseminated Encephalomyelitis (ADEM) and Transverse Myelitis (TM) are within the group of immune mediated disorders of acquired demyelinating syndromes. Both have been described in temporal association following various vaccinations in case reports and case series and have been evaluated in observational studies. A recent analysis conducted by The Global Vaccine Data Network (GVDN) observed an excess of ADEM and TM cases following the adenoviral vectored ChAdOx1 nCoV-19 (AZD1222) and mRNA-1273 vaccines, compared with historically expected background rates from prior to the pandemic. Further epidemiologic studies were recommended to explore these potential associations. We utilized an Australian vaccine datalink, Vaccine Safety Health-Link (VSHL), to perform a self-controlled case series analysis for this purpose. VSHL was selected for this analysis as while VSHL data are utilised for GVDN association studies, they were not included in the GVDN observed expected analyses. The VSHL dataset contains vaccination records sourced from the Australian Immunisation Register, and hospital admission records from the Victorian Admitted Episodes Dataset for 6.7 million people. These datasets were used to determine the relative incidence (RI) of G040 (ADEM) and G373 (TM) ICD-10-AM coded admissions in the 42-day risk window following COVID-19 vaccinations as compared to control periods either side of the risk window. We observed associations between ChAdOx1 adenovirus vector COVID-19 vaccination and ADEM (all dose RI: 3.74 [95 %CI 1.02,13.70]) and TM (dose 1 RI: 2.49 [95 %CI: 1.07,5.79]) incident admissions. No associations were observed between mRNA COVID-19 vaccines and ADEM or TM. These findings translate to an extremely small absolute risk of ADEM (0.78 per million doses) and TM (1.82 per million doses) following vaccination; any potential risk of ADEM or TM should be weighed against the well-established protective benefits of vaccination against COVID-19 disease and its complications. This study demonstrates the value of the GVDN collaboration leveraging large population sizes to examine important vaccine safety questions regarding rare outcomes, as well as the value of linked population level datasets, such as VSHL, to rapidly explore associations that are identified., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Objectives: We undertook an observational study to assess the impact of state-level partisanship and parents'/guardians' race/ethnicity on their degree of COVID-19 vaccine hesitancy., Material and Methods: We observed a pooled cross-section of 59,280 U.S. adults residing with children in the same household between June 29 and November 14, 2022. Using household-weighted logistic regression models, we evaluated the association between partisanship, race/ethnicity, and vaccine hesitancy, while controlling for other social determinants of COVID-19 vaccine hesitancy., Results and Conclusions: We found that children were less likely to receive a COVID-19 vaccine if they resided in Republican as compared to Democratic states, with the difference in probability greatest among those households where parents/guardians identified as White. We also found that children were less likely to receive a COVID-19 vaccine if their parents/guardians identified as White as compared to any other race/ethnicity, with the differences in probability greatest among households in Republican states., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Multiple vaccines have been approved to control COVID-19 pandemic, with Pfizer/BioNTech (BNT162b2) being widely used. We conducted a longitudinal analysis of the immune response elicited after three doses of the BNT162b2 vaccine in individuals who have previously experienced SARS-CoV-2 infection and in unexperienced ones. We conducted immunological analyses and single-cell transcriptomics of circulating T and B lymphocytes, combined to CITE-seq or LIBRA-seq, and VDJ-seq. We found that antibody levels against SARS-CoV-2 Spike, NTD and RBD from wild-type, delta and omicron VoCs show comparable dynamics in both vaccination groups, with a peak after the second dose, a decline after six months and a restoration after the booster dose. The antibody neutralization activity was maintained, with lower titers against the omicron variant. Spike-specific memory B cell response was sustained over the vaccination schedule. Clonal analysis revealed that Spike-specific B cells were polyclonal, with a partial clone conservation from natural infection to vaccination. Spike-specific T cell responses were oriented towards effector and effector memory phenotypes, with similar trends in unexperienced and experienced individuals. The CD8 T cell compartment showed a higher clonal expansion and persistence than CD4 T cells. The first two vaccinations doses tended to induce new clones rather than promoting expansion of pre-existing clones. However, we identified a fraction of Spike-specific CD8 T cell clones persisting from natural infection that were boosted by vaccination and clones specifically induced by vaccination. Collectively, our observations revealed a moderate effect of the second dose in enhancing the immune responses elicited after the first vaccination. Differently, we found that a third dose was necessary to restore comparable levels of neutralizing antibodies and Spike-specific T and B cell responses in individuals who experienced a natural SARS-CoV-2 infection., Competing Interests: Declaration of competing interest Author Renata Grifantini is currently employed by CheckmAb Srl. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024. Published by Elsevier Inc.)

Aim: To study the prevalence of neutralizing antibodies in healthcare workers and healthcare support personnel after the administration of the second dose of the BNT162b2 vaccine (Pfizer-BioNTech)., Materials and Methods: In December 2021, we undertook a study in the Health Department in Orihuela, Alicante (Spain), which consists of 1500 workers. We collected demographic variables about the study participants, and we performed a "point-of-care" immunochromatography test to measure the presence of neutralizing antibodies (OJABIO® SARS-CoV-2 Neutralizing Antibody Detection Kit, manufactured by Wenzhou OJA Biotechnology Co., Ltd. Wenzhou, Zhejiang, China) before the administration of the third dose of the vaccine., Results: We obtained complete information about 964 (64%) workers, which consisted of 290 men and 674 women. The average age was 45,8 years (min. 18, max. 68) and the average time since the last dose of the vaccine was 40,5 weeks (min. 1,71, max. 47,71). A total of 131 participants (13,5%) had suffered infection by SARS-CoV-2 confirmed using RT-PCR. The proportion of participants who showed presence of neutralizing antibodies was 38,5%. In the multivariable analysis, the time since the last dose of the vaccine (aOR week: 1,07; 95%CI: 1,04; 1,09) and previous infection by SARS-CoV-2 (aOR: 3,7; 95CI: 2,39; 5,63) showed a statistically significant association with the presence of neutralizing antibodies., Conclusions: The time since the administration of the last dose of the vaccine and the previous infection by SARS-CoV-2 determined the presence of neutralizing antibodies in 38,5% of the healthcare workers and support workers., (Copyright © 2024 The Author(s). Published by Elsevier España, S.L.U. All rights reserved.)

As information consumption plays a critical role in addressing vaccine hesitancy in the hybrid media environment, it becomes crucial to understand how individuals' use of a combination of channels and sources affects their vaccine hesitancy. Based on information repertoire approaches emphasizing the multiplicity of channels and sources, we investigated different patterns of information repertoire related to the COVID-19 pandemic and how these patterns affected vaccine hesitancy through different informational mechanisms. Our results based on a U.S. sample suggest that while a richer information repertoire related to increased confidence in vaccines through increased information verification, this richness also corresponded with deepened vaccine hesitancy through heightened cognitive elaboration and perceived information inconsistency. Our findings support the utility of repertoire approaches for better understanding health information acquisition in the complex media ecology.

Vaccines have reduced severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) morbidity and mortality, yet emerging variants challenge their effectiveness. The prevailing approach to updating vaccines targets the antibody response, operating under the presumption that it is the primary defense mechanism following vaccination or infection. This perspective, however, can overlook the role of T cells, particularly when antibody levels are low or absent. Here we show, through studies in mouse models lacking antibodies but maintaining functional B cells and lymphoid organs, that immunity conferred by prior infection or mRNA vaccination can protect against SARS-CoV-2 challenge independently of antibodies. Our findings, using three distinct models inclusive of a novel human/mouse ACE2 hybrid, highlight that CD8 + T cells are essential for combating severe infections, whereas CD4 + T cells contribute to managing milder cases, with interferon-γ having an important function in this antibody-independent defense. These findings highlight the importance of T cell responses in vaccine development, urging a broader perspective on protective immunity beyond just antibodies., (© 2024. The Author(s).)

The coronavirus disease 2019 (COVID-19) pandemic is a global threat, challenging health services' provision and utilization. This study aimed to assess compulsory vaccination coverage in 12 Sub-Saharan African countries two years following the COVID-19 pandemic using the Health Belief Model. A cross-sectional survey was conducted from November 1 to December 15, 2022. Multivariate logistic regression was conducted to identify the determinants of vaccination coverage. Among the 5032 respondents, 73.1% reported that their children received compulsory vaccination. The lowest coverage was observed in Ghana (36.5%), while the highest was in Burkina Faso and Congo (92.0%). Factors associated with non-vaccination included older mothers (adjusted odds ratio (AOR) = 1.04, 95%CI: 1.03-1.05), lower mothers' education, older children (AOR = 0.76, 95%CI: 0.60-0.96), children with chronic illnesses (AOR = 0.55, 95%CI: 0.45-0.66), and difficult accessibility to healthcare facilities (AOR = 11.27, 95%CI: 9.48-13.44). Low perceived risk, in which non-vaccinated children were believed to be at no higher risk for infectious diseases and the disease severity would not worsen among non-vaccinated children, increased the likelihood of non-vaccination (AOR = 2.29, 95%CI: 1.75-2.99 and AOR = 2.12, 95%CI: 1.64-2.73, respectively). Perceiving vaccines as unnecessary, and needless for breastfed babies increased the probability of non-vaccination (AOR = 1.38, 95%CI: 1.10-1.73 and AOR = 1.69, 95%CI: 1.31-2.19, respectively). Higher odds of non-vaccination were found when the provision of vaccine information did not motivate parents to vaccinate their children (AOR = 4.29, 95%CI: 3.15-5.85). Conversely, believing that vaccines were safe for children decreased the odds of non-vaccination (AOR = 0.72, 95%CI: 0.58-0.88). Parental perceptions and concerns should be considered in interventions aiming to increase compulsory vaccine acceptance and coverage., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Dichotomised debates in public health discourse regarding COVID-19 vaccine supply and vaccine hesitancy do not capture the realities of vaccine uptake in Palabek refugee settlement, northern Uganda. Issues of supply, which analyse manufacture and distribution, foreground global inequalities and political influences. In contrast, vaccine hesitancy, emphasing rectifying deficiencies in knowledge and trust, leaves little room for the politics that shape vaccine uptake. The 'vaccine anxieties' framework problematises these dichotomised debates and proposes consideration of bodily, social and political dimensions. This article builds on the vaccine anxieties framework in relation to ethnographic research conducted in Palabek. Using the worldview of Acholi refugees from South Sudan, a focus on 'suspicious business' demonstrates that debates surrounding vaccine supply and hesitancy are intertwined, and, additionally, suggests spiritual elements should be paid greater attention. In Palabek, inconsistencies in distribution directly impacted vaccine uptake. Furthermore, vaccine interventions that built on deficiency models did not work. Vaccine uptake was inseparable from its biopolitical context that continued to perpetuate the same unequal dynamics of power and control that kept wealth circulating amongst certain powers, whilst others faced worsening precarity but remained perpetual recipients of humanitarian assistance and global health intervention, with little prospect of meaningful change. Suspicious business captures fluid dynamics that move between spiritual and physical realms, capturing wider geopolitical dynamics as they are revealed in everyday lives. In doing so, this flexible approach reveals the centrality of the politics of COVID-19, whilst constantly incorporating evolving dynamics. This flexibility provides potential for improving vaccine uptake, if wider geopolitical inequalities are addressed., (Copyright © 2024 The Author. Published by Elsevier Ltd.. All rights reserved.)

Although Covid-19 was not the first pandemic, it was unique in the scale and intensity with which societies responded. Countries reacted differently to the threat posed by the new virus. The public health crisis affected European societies in many ways. It also influenced the way the media portrayed vaccines and discussed factors related to vaccine hesitancy. Europeans differed in their risk perceptions, attitudes towards vaccines and vaccine uptake. In European countries, Covid-19-related discourses were at the centre of media attention for many months. This paper reports on a media analysis which revealed significant differences as well as some similarities in the media debates in different countries. The study focused on seven European countries and considered two dimensions of comparison: between the pre-Covid period and the beginning of the Covid pandemic period, and between countries. The rich methodological approach, including linguistics, semantic field analysis and discourse analysis of mainstream news media, allowed the authors to explore the set of meanings related to vaccination that might influence actors' agency. This approach led the authors to redefine vaccine hesitancy in terms of characteristics of the "society in the situation" rather than the psychological profile of individuals. We argue that vaccine hesitancy can be understood in terms of agency and temporality. This dilemma of choice that transforms the present into an irreversible past and must be taken in relation to an uncertain future, is particularly acute under the pressure of urgency and when someone's health is at stake. As such, it is linked to how vaccine meaning is co-produced within public discourses., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

This study aimed to evaluate the effect of anti-pandemic measures, including wearing a face mask and receiving vaccinations, on interpersonal distance (IPD) during the normalization stage of the COVID-19 pandemic. Virtual reality (VR) technology was used to simulate the experimental environment and a confederate in different conditions. Thirty-one participants were asked to approach the virtual confederate, who could exhibit three vaccination states and two mask-wearing conditions, actively and passively in both indoor and outdoor environments. ANOVA results showed that the participants kept a smaller IPD from the confederate wearing a face mask (IPD = 125.6 cm) than from the one without a face mask (IPD = 154.2 cm). The effects of vaccination states were significant, with the largest distance for an unvaccinated confederate (IPD = 182.3 cm) and the smallest distance for the confederate who had received a booster vaccine (IPD = 111.5 cm). Significant effects of environment were also found, with the participants maintaining a larger IPD in an outdoor environment (IPD = 143.4 cm) than in an indoor room (IPD = 136.4 cm). Additionally, the IPD collected when the participants were passively approached (IPD = 149.6 cm) was significantly larger than that obtained when they actively approached the confederate (IPD = 130.3 cm). Moreover, when the participants faced a confederate who had received a booster vaccine and wore a mask, the IPD was not significantly different from that collected before the COVID-19 pandemic in both the active and passive patterns. These findings help us to better understand the nature of IPD and human behaviors during the normalization stage of the pandemic and provide scientific suggestions for policymakers to develop pandemic-prevention measures., (© 2023 The Authors. PsyCh Journal published by Institute of Psychology, Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.)

Background: COVID-19 vaccines have been widely used to control the SARS-CoV-2 pandemic. In individuals receiving replication-incompetent, adenovirus vector-based COVID-19 vaccines (eg, ChAdOx1 nCoV-19 [AstraZeneca] or Ad26.COV2.S [Johnson & Johnson/Janssen] vaccines), a very rare but serious adverse reaction has been reported and described as vaccine-induced immune thrombotic thrombocytopenia (VITT). The exact mechanism of VITT following Ad26.COV2.S vaccination is under investigation. Antibodies directed against human platelet factor 4 (PF4) are considered critical in the pathogenesis of VITT, suggesting similarities with heparin-induced thrombocytopenia. It has been postulated that components of these vaccines mimic the role of heparin by binding to PF4, triggering production of these anti-PF4 antibodies., Objectives: This study aimed to investigate the potential interaction between human PF4 and Ad26.COV2.S vaccine using several biophysical techniques., Methods: Direct interaction of PF4 with Ad26.COV2.S vaccine was investigated using dynamic light scattering, biolayer interferometry, and surface plasmon resonance. For both biosensing methods, the Ad26.COV2.S vaccine was immobilized to the sensor surface and PF4 was used as analyte., Results: No direct interactions between PF4 and Ad26.COV2.S vaccine could be detected using dynamic light scattering and biolayer interferometry. Surface plasmon resonance technology was shown to be unsuitable to investigate these types of interactions., Conclusion: Our findings make it very unlikely that direct binding of PF4 to Ad26.COV2.S vaccine or components thereof is driving the onset of VITT, although the occurrence of such interactions after immunization (potentially facilitated by unknown plasma or cellular factors) cannot be excluded. Further research is warranted to improve the understanding of the full mechanism of this adverse reaction., Competing Interests: Declaration of competing interests R.B. is a co-inventor on related vaccine patents. M.v.d.N.K., H.I., J.M.M., N.v.D., M.P., E.K., D.v.M., J.C., and R.B. are employees of Janssen Vaccines & Prevention B.V. M.v.d.N.K., N.v.D., D.v.M., J.V., J.C., and R.B. hold stock of Johnson & Johnson. C.P.-P., J.C.d.S.F., and J.V. are former employees of Janssen Vaccines & Prevention B.V., (Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.)

Background: Studies estimate that at least 7.5% of adults are affected by long-term symptoms such as fatigue or cognitive impairment after the acute phase of COVID-19. COVID-19 vaccination may reduce the risk of long COVID. Rehabilitation can have a positive impact on recovery. This study aims to present the experiences of people with long COVID with COVID-19 vaccination and rehabilitation. Such research is important because perceptions of these measures can impact healthcare utilization and health status., Methods: 48 adults with long COVID participated in this qualitative study, 25 of them in one-on-one interviews and 23 in focus groups. Participants were recruited via calls for participation on the websites and social media channels of two university hospitals and with the help of respondents' networks. The conversations were audio-recorded, transcribed, and analyzed using qualitative content analysis. Subsequently, the results were compared, interpreted, and discussed by scientific literature., Results: 35 study participants reported that they had received a COVID-19 vaccination and 16 of them stated that they had utilized a rehabilitation service. These participants had varying experiences with COVID-19 vaccination and rehabilitation. Nine of them stated that they developed long COVID despite vaccination before COVID-19. Ten participants reported vaccine reactions, and two participants reported severe side effects. Two participants reported persistent deterioration of their long COVID symptoms after vaccination. This led to uncertainty about the safety, benefits, and handling of COVID-19 vaccination. However, most participants perceived the vaccine as effective regarding milder COVID-19 sequelae. Four participants felt their rehabilitation was helpful and four participants felt it was unhelpful. Two persons found the combination of inpatient rehabilitation and rehabilitation sport helpful., Conclusions: Several implications can be derived from this study: (1) researchers should explore the effects of COVID-19 vaccination on long COVID symptoms; (2) vaccination campaigns should be more responsive to the perspectives of people with long COVID on vaccination; (3) care planners should build rehabilitation facilities specialized in long COVID; (4) rehabilitation providers should train their professionals regarding long COVID and develop rehabilitation programs tailored to different clinical pictures., Trial Registration: German register for clinical trials DRKS00026007, 09 September 2021., (© 2024. The Author(s).)

Introduction: Child immunization, though cost-beneficial, experiences varying costs influenced by individual facility-level factors. A real-time solution is to optimize resources and enhance vaccination services through proper method to measure immunization facility efficiency using existing data. Additionally, examine the impact of COVID-19 on facility efficiency, with the primary goal of comprehensively assessing child immunization facility efficiency in Pakistan., Methods: Utilizing survey data collected in four rounds from May 2018 to December 2020, the research focuses on doses administered and stock records for the preceding six months in each phase. In the initial stage, Data Envelopment Analysis (DEA) is utilized to compute facility efficiency, employing two models with varied outputs while maintaining consistent inputs. Model 1 assesses doses administered, encompassing three outputs (pentavalent vaccine 1, 2, and 3). Meanwhile, Model 2, focuses on stock used featuring a single output (total doses used). The inputs considered in both models include stock availability, staff members, cold chain equipment, vaccine carriers, and vaccine sessions. The second stage involves the application of two competing regression specifications (Tobit and Simar-Wilson) to explore the impact of the COVID-19 pandemic and external factors on the efficiency of these facilities., Results: In 12 districts across Punjab and Sindh, we assess 466 facilities in Model 1 and 455 in Model 2. Model 1 shows 59% efficiency, and Model 2 shows 70%, indicating excess stock. Stock of vaccines need to be reduced by from 36% to 43%. In the stage, COVID-19 period reduced efficiency in Model 1 by 10%, however, insignificant in Model 2., Conclusions: The proposed methodology, utilizing DEA, emerges as a valuable tool for immunization facilities seeking to improve resource utilization and overall efficiency. Model 1, focusing on doses administered indicates facilities low efficiency at average 59% and proves more pertinent for efficiency analysis as it directly correlates with the number of children vaccinated. The prevalent issue of overstocking across all facilities significantly impacts efficiency. This study underscores the critical importance of optimizing resources through the redistribution of excess stock with low efficiency., Competing Interests: The authors declare that they have no competing interests., (Copyright: © 2024 Ahmad et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)