Future Vaccine Research Articles

Update on the evolving landscape of pneumococcal capsule types: new discoveries and way forward.

SUMMARYStreptococcus pneumoniae (the "pneumococcus") is a significant human pathogen. The key determinant of pneumococcal fitness and virulence is its ability to produce a protective polysaccharide (PS) capsule, and anti-capsule antibodies mediate serotype-specific opsonophagocytic killing of bacteria. Notably, immunization with pneumococcal conjugate vaccines (PCVs) has effectively reduced the burden of disease caused by serotypes included in vaccines but has also spurred a relative upsurge in the prevalence of non-vaccine serotypes. Recent advancements in serotyping and bioinformatics surveillance tools coupled with high-resolution analytical techniques have enabled the discovery of numerous new capsule types, thereby providing a fresh perspective on the dynamic pneumococcal landscape. This review offers insights into the current pneumococcal seroepidemiology highlighting important serotype shifts in different global regions in the PCV era. It also comprehensively summarizes newly discovered serotypes from 2007 to 2024, alongside updates on revised chemical structures and the de-novo determinations of structures for previously known serotypes. Furthermore, we spotlight emerging evidence on non-pneumococcal Mitis-group strains that express capsular PS that are serologically and biochemically related to the pneumococcal capsule types. We further discuss the implications of these recent findings on capsule nomenclature, pneumococcal carriage detection, and future PCV design. The review maps out the current status and also outlines the course for future research and vaccine strategies, ensuring a continued effective response to the evolving pneumococcal challenge.

“You’re telling us to go first?!” COVID-19 pandemic and vaccination experiences among Aboriginal adults in Western Australia

Globally, Indigenous populations have been disproportionately impacted by pandemics. In Australia, though national infection rates with COVID-19 infections in Aboriginal and/or Torres Strait Islander people were lower in the first 12 months of the COVID-19 pandemic, there was soon a greater burden in Aboriginal and/or Torres Strait Island people once Omicron was circulating. Uptake of the COVID-19 vaccine was also lower among Aboriginal and/or Torres Strait Islander people. It was imperative to understand the stories of Aboriginal and/or Torres Strait Islander people in WA about their experience of the COVID-19 pandemic and vaccine rollout. Between September 2022 and October 2023, we conducted five face-to-face yarning workshops with Aboriginal and/or Torres Strait Islander people in Noongar Whadjuk Boodja (Perth metropolitan region, Western Australia). Yarns discussed COVID-19 experiences, knowledge and attitudes about COVID-19 and vaccination, reasons for or against COVID-19 vaccination, trusted sources of information, and knowledge of COVID-19 vaccination programmes for Aboriginal and/or Torres Strait Islander people. Data was thematically analysed in an inductive manner on NVivo, followed by a data interpretation forum with study investigators and community members. Across the five yarning workshops, we heard the stories and experiences of 38 Aborginal and/or Torres Strait Islander people. Many described the negative impact that the policies implemented to control COVID-19 had on their ability to connect with their community and practice traditional culture. Very few participants trusted government and any government information due to both historical and contemporary factors. This led participants to be wary of the fact they were among the first to be prioritised for COVID-19 vaccination in Australia. Though most participants (92%) had received at least one COVID-19 vaccine, there were high levels of COVID-19 vaccine hesitancy. The main reason for this was due to COVID-19 vaccine mandates; participants were, in essence, coerced acceptors of what they felt to be an unsafe vaccine that provided little protection against a mild disease. Our yarns identified high levels of COVID-19 vaccine hesitancy and circulation of misinformation amongst Perth-based Aboriginal and/or Torres Strait Islander people. Our findings also demonstrate that there were many unintended consequences of COVID-19 policies on Aboriginal and/or Torres Strait Islander people and culture. Future pandemic policies and vaccine programmes must consider the impact on not only the health of Aboriginal and/or Torres Strait Islander people but also the impact on community and culture.

Hindcasting Farmed Salmon Mortality to Improve Future Health and Production Outcomes.

Intracellular, free-floating and biofilm-forming bacterial pathogens have been implicated in summer mortality of farmed Chinook salmon, Oncorhynchus tshawytscha, in New Zealand. A mortality event in 2022 in the Pelorus Sound, Marlborough, was linked to high water temperatures (> 18°C), and bacterial skin disease associated with Piscirickettsia spp. (=Rickettsia-like organisms) and Tenacibaculum species. To understand the progression of infection and potential drivers of the mortality, simulation of the event was conducted using a networked susceptible, infectious and recovered (SIR) model. Parameter exploration shows that reconstruction of observed mortality rates across three affected farm sites was possible. The best SIR simulations identified plausible values for key drivers of disease, which are consistent with previously estimated disease parameter ranges for Piscirickettsia salmonis. Our modelling shows the 2022 Pelorus Sound event likely experienced spread of bacterial pathogens within healthy fish populations at salmon farm sites over a 10-week long incubation period, before elevated mortality was observed. We show evidence that vaccine use at one site likely prevented 10% higher mortality and that an alternative site for the vaccination could have further reduced mortalities. This result highlights the importance of future vaccine developments in aquaculture and the potential to improve vaccine efficacy through considered site selection.

MRNA Vaccines: Unlocking Potential, Exploring Applications, and Envisioning Future Horizons.

In recent years, there have been notable strides in developing mRNA vaccines, resulting in the creation of potent immunizations against diverse diseases. This review examines the most recent advancements in this field, focusing on their implications for future vaccine development. The pursuit of heightened vaccine efficacy is investigated through cutting-edge methods in adjuvant selection, delivery system optimization, and antigen selection. The review also explores the potential for personalized vaccines based on genetic profiles, along with the latest techniques to ensure vaccine stability and extend shelf life. Highlighting the versatility of mRNA vaccines in addressing emerging infectious diseases and their variations, the review underscores the significance of swift response plans and advanced technologies to counter evolving viral mutations. In summary, this in-depth analysis emphasizes how mRNA vaccines hold transformative potential in reshaping both therapeutic and preventive strategies. Notable achievements include the creation of extremely potent mRNA vaccinations against the SARS-CoV-2 virus, resulting in the COVID-19 pandemic. Ongoing efforts to address challenges like long-term immune protection and increase the effectiveness and stability of mRNA vaccines are also discussed. This review's main goal is to provide a thorough summary of current advancements in mRNA vaccine technology while exploring how these advances may impact future approaches to treating and preventing different diseases.

P0632 Analysis of serological responses to SARS-Cov-2 vaccination in patients with Inflammatory Bowel Disease in India identifies low BMI as an independent determinant of vaccine non-response

Abstract Background Studies of patients with inflammatory bowel diseases (IBD) from Western countries have demonstrated that serological responses to mRNA and vector-based vaccines are differentially impacted by IBD therapies. Little is known regarding antibody responses in patients with IBD residing in low- and middle-income countries (1). In this study, we investigate the factors which may influence the inhibitory and total antibody responses to SARS-CoV-2 in two centers in Northern India. Methods We studied 180 IBD patients in Chandigarh and New Delhi, India, who received two doses of a COVID-19 vaccine. All patients received Oxford-AstraZeneca equivalent Covishield (n=149) or inactivated virus vaccine Covaxin (n=31) between January 2021 and December 2022. We measured anti-S and anti-N antibody levels and performed inhibition assays to measure the inhibition of ACE2 on SARS-CoV-2 binding against alpha, delta, and omicron variants after first and second vaccine doses. Univariate and multivariate analyses were performed to identify determinants of vaccine response. Results On univariate analysis, IBD patients taking steroids (p= 0.019), immunomodulators (p= 0.047), or infliximab (p= 0.0057) had lower responses after dose 2 for any vaccine compared to those not on these medications or receiving 5-ASAs. Low BMI was associated with reduced rates of seroconversion in univariate analysis. For every fall in BMI by 1, the average ACOV2S V2 anti-Spike level was reduced by 8.2 (Figure 1). Additionally, 97% (28/29) of vaccinated IBD patients with a BMI greater than or equal to 25 reached the maximum anti-Spike value after their second dose of a COVID-19 vaccine. Multivariate analysis comparing gender, IBD type, smoking status, comorbidities, IBD medications, and a history of COVID-19 diagnosis revealed that low BMI (dose 1: OR: 1.12 [CI: 0.084, 0.136]; dose 2: 1.11 [0.076, 0.128]), infliximab (dose 1: 1.67 [-.92, 1.94]), and patients on steroids (dose 1: 1.50 [-1.384, 2.195]; dose 2: 0.200 [-3.76 0.54]) were each independent determinants of lower seroprevalence levels after receiving a dose of Covishield or Covaxin. Conclusion Immunosuppressive drug therapy and reduced BMI emerge as determinants of sub-optimal seroconversion rate in this patient population. The association with low BMI represents a unique finding in this population, and directly contrast with studies reported in Europe & North America. These data are useful for future pandemic vaccine considerations in patients with IBD. References (1)Wong SY, Wellens J, Helmus D, et al. Geography Influences Susceptibility to SARS-CoV-2 Serological Response in Patients With Inflammatory Bowel Disease: Multinational Analysis From the ICARUS-IBD Consortium. Inflamm Bowel Dis. 2023;29(11):1693-1705. doi:10.1093/ibd/izad097

The cost-effectiveness of vaccination against COVID-19 illness during the initial year of vaccination.

Substantial investments by government programs and private health plans subsidized the costs of COVID-19 vaccine doses and vaccine administration. The objective of this study was to evaluate the cost-effectiveness of vaccination against COVID-19 illness during the initial year of COVID-19 vaccination (2021). Using a simulation model, we projected outcomes for hypothetical cohorts of US adults aged 18 and older, stratified by age and risk status for complications, comparing vaccination and no vaccination in the context of recommended concomitant prevention strategies (e.g., masking, social distancing). Vaccination against COVID-19 illness and complications used a pooled vaccination strategy for the 3 products available in 2021. Primary outcome measures included incremental cost-effectiveness ratio (ICER), projected costs, and projected quality-adjusted life years (QALYs). The model was parameterized using US epidemiologic, clinical, and cost data and the analysis used the healthcare and societal perspectives. For vaccination against COVID-19 illness compared with no vaccination, vaccination yielded cost savings and QALY gains for all adult age and risk groups using the societal perspective. Using a healthcare sector perspective, ages 18-39years required a net investment with ICERs ranging from $8400 to $15,000/QALY. Scenarios evaluating vaccine incentive programs mostly yielded ICERs <$100,000/QALY except for worker bonuses of $500 which yielded ICERs of $22,000 to $134,000/QALY. Results were most sensitive to costs of vaccination (dose cost, administration cost, travel and vaccination time costs) across uncertainty analyses. Investment in the 2021 vaccination program was attractive from an economic perspective even when using a very conservative approach to the analysis. Future vaccination programs in the US, with different associated cost structures, should be assessed to ensure ongoing value for COVID-19 vaccination.

Antibody Responses to mRNA COVID-19 Vaccine Among Healthcare Workers in Outpatient Clinics in Japan.

This study aimed to assess the antibody response to SARS-CoV-2 vaccines among healthcare workers (HCWs) from multiple outpatient clinics in Japan, examining the effects of baseline characteristics (e.g., sex, age, underlying condition, smoking history, occupation) and prior infections. A total of 101 HCWs provided serum at four time points between October 2020 and July 2023. HCWs received two to six doses of mRNA vaccine (BNT162b2 or mRNA-1273). Anti-nucleocapsid (N) and anti-spike (S) IgG antibodies against the ancestral Wuhan strain were measured using the Abbott Architect™ SARS-CoV-2 IgG assay. Univariate and regression analysis evaluated factors such as past infections, age, sex, smoking, underlying condition, and occupation. After four to six doses, the median anti-S IgG titer in uninfected HCWs was 1807.30 BAU/mL, compared to 1899.89 BAU/mL in HCWs with prior infections. The median anti-N IgG titer was 0.10 index S/C in uninfected HCWs and 0.39 index S/C in infected HCWs. HCWs with prior infection had anti-S IgG titers 1.1 to 5.8 times higher than those without. Univariate and multivariate analyses indicated infection and vaccination significantly increased anti-S and anti-N IgG titers. Age, sex, smoking history and occupation did not influence antibody titers while underlying conditions were associated with lower anti-N IgG titers. Infection and vaccination were strongly associated with an increase in anti-S and anti-N IgG titers; however, the impact of hybrid immunity appeared to be limited and varied depending on the timing of the sampling. These findings provide valuable insights for developing personalized vaccination strategies and future vaccine development.

Vaccination against SARS-CoV-2 provides low-level cross-protection against common cold coronaviruses in mouse and non-human primate animal models.

The common cold coronaviruses are a source of ongoing morbidity and mortality particularly among elderly and immunocompromised individuals. While cross-reactive immune responses against multiple coronaviruses have been described following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and vaccination, it remains unclear if these confer any degree of cross-protection against the common cold coronaviruses. A recombinant fowl adenovirus vaccine expressing the SARS-CoV-2 spike protein (FAdV-9-S19) was generated, and protection from SARS-CoV-2 challenge was shown in K18-hACE2 mice. Vaccinated mice were also challenged with the common cold coronaviruses human coronavirus (HCoV)-OC43 and HCoV-NL63 by the intranasal route, and viral shedding and lung burden were reduced in these groups compared to unvaccinated animals. Histopathological analysis of lung tissues revealed significantly less inflammation and lower pathology scores in mice that received FAdV-9-S19 . Because no mouse model for the coronavirus HCoV-229E exists, we vaccinated and challenged cynomolgus macaques to evaluate cross-protection against HCoV-229E. Animals were monitored for clinical signs of disease and viral shedding. Infectious virus was detected in both groups throughout the course of infection; however, vaccinated animals showed reduced viral shedding at multiple time points after infection. Histopathological analysis of lung tissues following challenge also indicated a more moderate disease in the vaccinated animals. Therefore, vaccination with FAdV-9-S19 also provided a moderate cross-protection against HCoV-229E disease in the cynomolgus macaques infection model. Our study demonstrates that vaccination with a recombinant fowl adenovirus expressing SARS-CoV-2 spike protein can provide a low-level cross-protection against beta- and alphacoronaviruses. These findings are important for the design of future pan-coronavirus vaccines.IMPORTANCEThe common cold coronaviruses are a source of ongoing morbidity and mortality particularly among elderly and immunocompromised individuals, and no vaccine is currently available. Cross-reactive immune responses have been described following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination; however, it remains unclear what degree of cross-protection they confer against the common cold coronaviruses. We demonstrate that both humoral and cell-mediated immune responses provide a low-level cross-protection, resulting in reduced viral load and pathology for the common cold coronaviruses OC43 and NL63 in mouse models. Additionally, we present a novel non-human primate (NHP) model of infection with the common cold coronavirus 229E, demonstrating that it mimics the disease observed in humans and can serve as a model for future vaccine studies, as cross-protection was also observed. This is significant as it suggests that current vaccines could provide a low-level protection against other coronaviruses and could serve as part of vaccination strategy against future novel coronaviruses.

Effects of different vaccination regimes on the immunodiagnosis of tuberculosis in goats and evaluation of defined antigens

Tuberculosis (TB) in goats is a chronic infectious disease caused by Mycobacterium tuberculosis complex (MTBC) organisms that pose a great health and economic challenge for the caprine industry in some European and developing countries. It is also a zoonotic disease posing a risk for public health. The control programs of the disease are based on a test-and-slaughter strategy, and vaccination is not feasible with available vaccines due to its interferences with the current TB immunodiagnosis. There is still a need for the development of an effective TB vaccine and, concurrently, diagnostic methods that allow differentiation between infected and vaccinated animals (DIVA approach). In this study, we investigated the interferences caused by the tuberculin (PPD)-based TB diagnostic tests in goats immunized by different mucosal and parenteral vaccination strategies: three single-dose strategies based on intranasal administration of BCG and two heat-inactivated M. bovis (HIMB) vaccines, and two prime-boost strategies based on parenteral BCG or HIMB priming and intranasal HIMB boosting. In addition, the defined antigens ESAT-6, CPF10, and EspC were evaluated as alternative diagnostic reagents to PPDs. At week 14 after prime vaccination of the animals, skin tests, IFN-γ release assay, and antibody detection assays were performed. The two prime-boosted and the single-dose intranasal BCG groups displayed greater cell-mediated immune responses to PPDs than the two single-dose intranasal HIMB vaccines. However, the use of reagents based on the defined antigens eliminated or reduced the vaccine-induced diagnostic interferences in all groups. Based on these results, the use of defined antigens in the current immunodiagnostic tests appears to be suitable in a future goat TB vaccination scenario.

Seasonal Influenza Vaccination Uptake Among Australian Healthcare Professionals: An Archetype for Success.

Qualitative research suggests there may be identifiable characteristics that form a health professional (HCP) archetype associated with habitual seasonal influenza vaccination (SIV). However, the validity of this archetype requires further investigation, ideally within a theoretical framework that can elucidate this association and its generalisability to other vaccines. This study aims to confirm key HCP archetype characteristics associated with SIV, as informed by prior qualitative research findings, and test the generalisability of the association between this archetype and SIV to COVID-19 vaccine acceptance. A cross-sectional survey was designed and distributed to an Australian HCP sample consisting of practicing nurses, midwives, pharmacists, and medical practitioners. The anonymous online survey measured key characteristics that predict vaccination behaviour and intention. Most participants (n = 173) demonstrated habitual SIV behaviour (77.91%) associated with the intention to vaccinate in the future. Survey findings supported the HCP archetype, as key constructs were associated with vaccination intention and behaviour, including heightened professional responsibility, vaccine confidence, and protection of self and patients. Furthermore, results suggested progressing vaccination intention to behaviour, overcoming vaccine complacency, is possible through the provision of free, accessible vaccination services. These critical factors were broadly generalisable to the COVID-19 vaccine. A vaccination-positive HCP archetype, supported by access to free, convenient vaccination services, was associated with the likelihood of future vaccination behaviour, including in future pandemic response scenarios. However, it will be important to ensure that HCP vaccine knowledge gaps are minimised to enhance trust in this cohort to enable broad success.

A large geno-spatial cluster of multi-drug resistant tuberculosis outbreak in a western district of Thailand.

The growing issue of drug resistance, particularly multidrug-resistant TB (MDR-TB), has exacerbated this problem. The rise of drug resistance TB is a severe global health concern. In Thailand, a persistent community outbreak of primary MDR-TB has been confirmed in the Tha Maka district of Kanchanaburi province, with an increasing prevalence of MDR-TB among newly diagnosed pulmonary tuberculosis cases. It was the first site in Thailand where a cluster of MDR-TB, caused by the Asian African 3 Modern Beijing strain, and XDR-TB, caused by L2.1, outbreaks were reported. This study aims to assess the MDR-TB outbreak in detail by characterizing the genomic profiles of the prevalent MDR-TB strains and examining their geographical distribution within the affected district. Through whole-genome sequencing (WGS) and bioinformatic analysis of 188 MTB isolates, the study identified three major phylogenetic lineages: the East Asian lineage (L2, 92 %), the Indo-Oceanic lineage (L1, 5.9 %), and the Euro-American lineage (L4, 2.1 %). The detailed sub-lineage distribution offers valuable insights into the predominant genetic clusters of M. tuberculosis within the sampled population. Notably, Lineage 2, specifically the L2.2.M3 sub-lineage, stood out as the dominant strain of MDR-TB, accounting for 77.7 % of the isolates. This finding underscores the significant prevalence of the L2.2.M3 sub-lineage and its potential role in the local transmission dynamics of tuberculosis. The high proportion and genetic homogeneity of the L2.2.M3 cluster among MDR-TB patients may indicate the strain's adaptation for more effective transmission within the Thai population. The increasing prevalence of this pathogenic strain could significantly impact tuberculosis control programs. Early diagnosis and contact tracing with chemotherapeutic preventive therapy for MDR-TB will be essential in inhibiting the spread and reactivation of these strains. Additionally, further studies are needed to prospectively identify transmission routes through contact tracing and real-time genotypic methods. It will also be crucial to ensure that future vaccines and/or recommended chemoprophylaxis therapy for MDR-TB will provide protection against these emerging strains.

Surveillance of Adverse Events Following Varicella Vaccine Immunization in Zhejiang Province, China, from 2020 to 2022.

Background: China has a high incidence rate of varicella yet a low coverage rate of the varicella vaccine (VarV), with safety concerns being a leading cause of the lack of vaccination willingness. This study aimed to describe VarV-related adverse events following immunization (AEFIs) and analyze their characteristics in Zhejiang, China, 2020-2022. Methods: VarV-related AEFIs in Zhejiang Province from 1 January 2020 to 31 December 2022 were collected through the Chinese National AEFI Information System (CNAEFIS) for a descriptive epidemiological analysis. Results: From 2020 to 2022, a total of 1477 VarV-related AEFI cases were reported (incidence rate: 34.79/100,000). The three most frequently reported clinical symptoms of common adverse reactions were fever, redness, and induration at the vaccination site. The distribution of VarV-related AEFIs varied significantly by age, dose, severity, and season. VarV-related AEFIs were more likely to be non-severe adverse events that occurred in the summer and winter seasons following the first dose of vaccine and among those under 3 years old. The top three regions with the highest incidence rates were Lishui City (59.53/100,000), Quzhou City (41.05/100,000), and Jinhua City (40.43/100,000). Most of the cases achieved full recovery without treatment (96.21%), and the rest were successfully treated without any sequelae. Conclusions: VarV demonstrates a safe profile in Zhejiang Province. Most VarV-related AEFIs are common reactions without requiring treatment, and the rates of rare and severe AEFIs remain low. Consistent monitoring, investigation, and diagnosis are needed to guide future VarV research and vaccination strategy adjustment. Our findings call for more policy changes, such as integrating VarV into China's National Immunization Program and conducting more trials to evaluate the safety and effectiveness of VarV.

Barriers and Predictors of Lyme Disease Vaccine Acceptance: A Cross-Sectional Study in Poland.

Lyme disease (LD) is a major public health problem in Europe and the United States, with increasing incidence and not many prevention options. Vaccine hesitancy might be a significant barrier to successful vaccination campaigns having in mind previous vaccine development failures. This study aimed to evaluate the public's perception of LD vaccination in Poland, assess willingness to vaccinate, and identify factors influencing vaccination attitudes. A cross-sectional survey was conducted among parents of children hospitalized at the University Children's Hospital in Bialystok, Poland. The survey consisted of 29 questions regarding demographics, LD knowledge, vaccine attitudes, and perceived risks. Data were collected between January and December 2023 and analyzed using descriptive and inferential statistics to identify predictors of respondents' positive vaccination attitudes. A total of 503 valid responses were analyzed. Most respondents (72.4%) showed positive attitudes towards vaccination, while 18.5% were neutral and 9.1% were negative. Trust in health experts emerged as an important predictor of vaccination acceptance (OR 22.84; p < 0.001). More than 80% of participants recognized an LD vaccine as necessary, and 64.21% believed it would reduce their concerns about LD. Willingness to vaccinate was influenced by general positive vaccine attitudes, recognized danger of LD, and belief in the vaccine's ability to ease fears. Notably, 40.8% of respondents were uncertain about vaccine risks, with this group tending to be younger, less educated, and expressing lower trust in medical professionals. Public perception of LD in Poland indicates a high acceptance of a potential LD vaccine. Still, addressing vaccine hesitancy remains critical, particularly among undecided or neutral respondents. Building trust in healthcare professionals and addressing safety worries are important to increasing future LD vaccine use.

Neutralization of omicron subvariants and antigenic cartography following multiple COVID 19 vaccinations and repeated omicron non JN.1 or JN.1 infections

The ongoing emergence of SARS-CoV-2 variants, combined with antigen exposures from different waves and vaccinations, poses challenges in updating COVID-19 vaccine antigens. We collected 206 sera from individuals with vaccination-only, hybrid immunity, and single or repeated omicron post-vaccination infections (PVIs), including non-JN.1 and JN.1, and evaluated neutralization against omicron BA.5, BA.2.75, BQ.1.1, XBB.1.16, XBB.1.5, and JN.1. Neutralizing antibodies exhibited a narrow breadth against BA.5 and BA.2.75 and failed to neutralize BQ.1.1 and XBB lineages after three to five doses of the ancestral monovalent vaccine. Hybrid immunity elicited higher neutralizing titers than vaccination alone, but titers remained relatively low. A single omicron PVI elicited lower neutralization titers to all variants compared to wild-type (WT), indicating immunological imprinting. Repeated omicron PVIs, particularly JN.1, slightly mitigated these effects by increasing broad neutralization responses to all variants, though not significantly. Antigenic mapping demonstrated that XBB lineages and JN.1 are antigenically distant from WT and also evaded antibodies induced by earlier omicron variants (BA.1–5) PVIs. However, repeated JN.1 PVIs shortened this antigenic distance, indicating broader neutralization across omicron variants. These findings highlight SARS-CoV-2 immunity following various antigen boosts and the impact of repeated omicron JN.1 exposure on broad immunity, informing future COVID-19 vaccination strategies.

A Bibliometric Analysis on Multi-epitope Vaccine Development Against SARS-CoV-2: Current Status, Development, and Future Directions.

The etiological agent for the coronavirus disease 2019 (COVID-19), the SARS-CoV-2, caused a global pandemic. Although mRNA, viral-vectored, DNA, and recombinant protein vaccine candidates were effective against the SARS-CoV-2 Wuhan strain, the emergence of SARS-CoV-2 variants of concern (VOCs) reduced the protective efficacies of these vaccines. This necessitates the need for effective and accelerated vaccine development against mutated VOCs. The development of multi-epitope vaccines against SARS-CoV-2 based on in silico identification of highly conserved and immunogenic epitopes is a promising strategy for future SARS-CoV-2 vaccine development. Considering the evolving landscape of the COVID-19 pandemic, we have conducted a bibliometric analysis to consolidate current findings and research trends in multi-epitope vaccine development to provide insights for future vaccine development strategies. Analysis of 102 publications on multi-epitope vaccine development against SARS-CoV-2 revealed significant growth and global collaboration, with India leading in the number of publications, along with an identification of the most prolific authors. Key journals included the Journal of Biomolecular Structure and Dynamics, while top collaborations involved Pakistan-China and India-USA. Keyword analysis showed a prominent focus on immunoinformatics, epitope prediction, and spike glycoprotein. Advances in immunoinformatics, including AI-driven epitope prediction, offer promising avenues for the development of safe and effective multi-epitope vaccines. Immunogenicity may be further improved through nanoparticle-based systems or the use of adjuvants along with real-time genomic surveillance to tailor vaccines against emerging variants.

Enhancing COVID-19 Vaccine Acceptance Within Scotland Black, African, and Caribbean Communities and Lessons for Future Vaccination Programmes.

This study highlights how the intersection of multiple factors shapes the experiences of Scotland's Black, African, and Caribbean communities in their access and uptake of COVID-19 vaccines in the vaccination programme's first, second, and booster stages. There was particular interest in understanding the vaccination journey, from scheduling an appointment to attending the appointment. Data in this study was collected between the 1 and 30 April 2022 using a triangulated approach, including a survey (with 408 responses), interviews (26), and focus group discussions (5 groups involving 30 participants). The study shows that 62% of respondents found scheduling a COVID-19 appointment easy, with less than 1% of respondents indicating that the process was complex. Online booking, appointment letters, and walk-in appointments were the most common ways of securing vaccination appointments. Letter appointments, specifically the blue envelope, were beneficial reminder mechanisms. It also provided information about COVID-19 vaccines and what to expect when attending the appointments. Other forms of securing vaccination appointments, such as through GP surgeries, were less commonly used. Around 21.5% of participants felt that receiving an appointment letter provided useful pre-vaccination information and a helpful reminder for their appointment. The accessibility of the vaccination centre, professionalism of the staff, and friendly approach enhanced the vaccine user access, use, and experience of COVID-19 vaccination.

Expert recommendations on mass population vaccination

Mass vaccination represents a highly effective strategy for accelerating disease control while simultaneously reducing incidence and mortality rates. By developing comprehensive plans and standards for mass vaccination, it is feasible to optimize resource allocation and swiftly enhance vaccination coverage, thereby preventing, controlling, or interrupting outbreaks or epidemics of specific infectious diseases. To standardize the mass vaccination process and establish a population immunity barrier in an orderly, efficient, and safe manner, a panel of experts was convened to develop the Recommendations on Mass Vaccination. These recommendations are grounded in the requirements of relevant policies and regulations in China, as well as the insights gained from the mass vaccination campaign for COVID-19 vaccines conducted in the country. The recommendations outline the system requirements pertaining to initiation conditions, departmental coordination, responsibilities, mobilization, operational specifications, and responses to vaccine reactions, among other aspects of mass vaccination implementation, so as to serve as a reference for future mass vaccination initiatives and the formulation of related policies.

Complete Genome Characterization of Canine Adenovirus From Türkiye With Next-Generation Sequencing.

Determining the complete genome sequence data of adenoviruses has recently become greatly important due to their use by scientists as vectors in cancer studies and other fields, including vaccine development. However, the GenBank database currently has few complete genome sequences of adenoviruses, which are known for their large genomes. To address this gap, we analysed next-generation sequencing data obtained from our previous study to provide the complete genome sequence of the canine adenovirus-2 strain. For the obtained canine adenovirus-2 strain (OQ596341), comparative genomics, recombination and phylogenetic analysis were conducted. This sequence was compared and phylogenetically analysed with the 20 complete genome sequences of canine adenovirus previously reported in GenBank worldwide, as well as partial E3 ORFA sequences obtained from Türkiye. The nucleotide similarity rates of the sequence obtained from this study with other CAdV-2 whole genomes are over 99.04%. The gene alignment results reveal that the OQ596341 was found to be closely related to the AC000020 reference genome and LC557011. There are two recombination events related to the genome in this study. Comparisons with other complete genome sequences revealed several previously unseen mutations. These mutations include H34Y in the E1A gene; P55A in the E1B 55K gene; D13N and D202N in the IVa2 gene; K679R, V934I and K989N in the Pol gene; E205K in the pTP gene; T455A in the pIIIa gene; A310V in the V gene; G151R in the protease gene; E268K in the 100K gene; G66S and G141S in the 33K gene; T14A, E250K, D287N and I293T in the E3 ORFA gene; and L193F in the E434K gene. Moreover, a comparison with partial sequences obtained from Türkiye revealed the E250K mutation in the E3 ORFA gene, which we report for the first time in Türkiye. The complete CAdV-2 genome sequence obtained in the present study is the first sequence from Europe. Comparative analysis with other genomes revealed some unique mutations. This study is the first to report the E250K amino acid change in the E3 ORFA gene in Türkiye. We anticipate that this data can be used in future CAdV-2 vaccine development studies. Further studies are recommended to evaluate the impact of these mutations on viral tropism and other host interactions.

"They need to speak a language everyone can understand": Accessibility of COVID-19 vaccine information for Canadian adults with intellectual and developmental disabilities.

Accessible vaccine information is one vital component of effective vaccination programs, however, there is limited research that explores how people with disabilities engage with public health messaging. This study aimed to understand how adults with intellectual and developmental disabilities (IDD) and their caregivers navigated Canada's public health communications regarding COVID-19 vaccines. A national survey on the accessibility of vaccine information was conducted in the spring and summer of 2022. Surveys were completed by 208 adults with IDD, 102 family caregivers and friends, and 54 staff. Quantitative data were analyzed descriptively, and descriptive qualitative content analysis was applied to open-ended survey responses. Vaccine information was difficult to understand and was not accessible to many people with IDD and their caregivers. Approximately 75% of adults with IDD found COVID-19-related information challenging to comprehend, followed by 69% of family/friends and 56% of staff. All three groups indicated they felt overwhelmed by the large quantity of information they had to navigate (adults with IDD, 72%; family/friends, 65%; staff, 70%) and experienced difficulties such as finding trustworthy sources and identifying vaccine misinformation and disinformation. Respondents offered recommendations to improve public health messaging and the accessibility of future vaccine campaigns. Our study explored the experiences of Canadian adults with IDD and caregivers while navigating COVID-19 vaccine information, revealing significant barriers. To address these barriers and improve vaccine uptake, public health communications must ensure accessibility throughout every stage of immunization, including education campaigns, appointment booking, vaccination appointment, and aftercare services. Recommendations include using Easy Read language and multiple formats, supporting caregivers and community groups, and enlisting trusted community messengers to disseminate accurate information and build confidence among adults with IDD and their caregivers.

Dynamic Changes and Trends of SARS-CoV-2 Antibodies Induced by Infection and Vaccination Across Multiple Time Points.

As the COVID-19 pandemic continues, increasingly complex vaccination and infection histories have made it urgent to investigate the antibody dynamics in populations with hybrid immunity. This study aimed to explore the multi-time-point dynamics of SARS-CoV-2 IgG antibody levels in a community-based population in Jiangsu Province, China, following the Omicron BA.5 wave, as well as the long-term persistence of IgG antibodies nearly 2 years postinfection. A total of 2737 participants across Jiangsu Province were followed up at three different time points over a 6-month period (December 2022-June 2023). Additionally, a cross-sectional serological survey was conducted in October 2024, involving 230 participants to assess long-term antibody persistence. We used generalized additive models to fit antibody dynamics curves, generalized linear mixed models to explore factors influencing antibody levels, and Kaplan-Meier survival analysis to estimate cumulative seroreversion rates. Our findings revealed that, following the large-scale Omicron BA.5 infections, over 85% of the population initially exhibited seropositive IgG levels. Older individuals (> 65 years) had significantly lower antibody levels and faster rates of decline compared to younger participants. Booster immunization reduced the risk of seroreversion by 59.79% (95% CI: 29.63%-76.46%), while individuals with multiple infections experienced slower antibody decay. In the cross-sectional survey conducted 22 months postinfection, the IgG seropositivity rate remained high, exceeding 98%, indicating sustained immunity at the population level. This study provides valuable insights into the dynamics and persistence of IgG antibody levels following large-scale infection. The results underscore the importance of tailored booster immunization strategies to sustain long-term immunity, especially in vulnerable groups like the elderly. Additionally, ongoing serological monitoring is essential for assessing population immunity and informing future vaccination strategies.