Expert Review of Vaccines最新文献

Background: In China, low awareness of the herpes zoster vaccine (HZV) hinders vaccination uptake among older adults. This study aimed to investigate HZV awareness rates and associated factors among older urban Chinese adults to inform targeted interventions.

Research design and methods: A cross-sectional survey on the awareness of HZV was conducted from December 2024 to January 2025 among adults aged ≥60 years in 6 cities of China. Univariate and multivariable logistic analyses were performed to evaluate the factors related to the rate of awareness of HZV, including the interaction between income and education.

Results: The overall awareness rate was low at 43.4%. Awareness was significantly associated with self-reported health status, monthly income, educational level, and preretirement occupation (all p < 0.05). A significant synergistic effect was observed, where individuals with both high education and high income demonstrated markedly higher awareness levels.

Conclusions: The awareness of HZV among older adults in urban China is inadequate and inequitably distributed. Significant disparities in awareness, which were linked to socioeconomic status and occupational history, were identified. These findings pinpoint specific, underserved populations that should be prioritized for targeted health education strategies to bridge the knowledge gap and promote informed decision-making regarding HZ vaccination.

Objectives: Immunocompromised (IC) patients are at increased risk of herpes zoster (HZ; i.e. shingles) and subsequent complications which can significantly impact quality of life. While current evidence indicates a strong disease presence of HZ in Türkiye, literature on the management of HZ in this population is lacking.

Methods: We conducted a survey with 6 disease experts from various medical specialties in Türkiye to understand their opinions on the burden of HZ and the challenges faced by IC patients, in order to establish a comprehensive and evidence-based expert consensus.

Results: Experts agreed that the burden of HZ is significant among IC patients in Türkiye. However, they identified a need for increased local epidemiological data to better understand the health impact of HZ in Türkiye. Improved dissemination of information regarding HZ to physicians was also highlighted to increase awareness of HZ.

Conclusions: Strategies to enhance current practices and increase vaccine coverage should include incorporation of HZ vaccination into official guidelines and recommendations, with full or partial reimbursement for HZ vaccination in IC patients. Setting up official or society-initiated online platforms could also support ongoing collaboration and provide continuously updated guidelines reflecting the latest advances in HZ vaccination and disease management.

Background: In the U.S.A. three prophylactic interventions are approved for the prevention of respiratory syncytial virus (RSV) lower respiratory tract disease (LRTD) in infants: nirsevimab and clesrovimab (extended half-life monoclonal antibodies) and the maternal RSVpreF vaccine. We compared the impact of these interventions on RSV-LRTD events and costs versus the previous standard-of-practice (SoP; palivizumab-only strategy).

Research design and methods: Using a static decision-analytic model, we estimated the public health impact of nirsevimab, clesrovimab, and RSVpreF following the latest recommendations on RSV-related outcomes and costs in a US birth cohort during their first RSV season compared to the pre-2023 SoP.

Results: The model estimated that nirsevimab would avert 364,204 RSV-LRTDs including 32,404 hospitalizations, saving $1,289 million in direct and indirect costs. Depending on the assumed duration of protection, clesrovimab was estimated to avert 173,276-261,358 RSV-LRTDs of which 23,957-30,483 were hospitalizations, resulting in savings of $912-$1,150 million in total costs. RSVpreF maternal vaccination would avert 76,915 RSV-LRTDs including 9,649 hospitalizations, equating to $345 million in total cost savings.

Conclusions: While all three interventions are estimated to reduce RSV-LRTD burden in infants, all-infant protection with nirsevimab was estimated to avert more events and associated medical costs for all infant subgroups compared to clesrovimab or RSVpreF.

Background: Evidence regarding the comparative safety of different COVID-19 vaccines remains limited. This study aims to characterize and compare the safety profiles of five COVID-19 vaccines in terms of adverse reactions after immunization.

Research design and methods: We conducted a retrospective analysis of adverse reactions reported among adults aged 18-59 years from nine clinical trials. The analyzed vaccines included inactivated, recombinant protein, intranasal influenza-vectored, aerosolized and intramuscular Ad5 vectored COVID-19 vaccines. Factor analysis and association rule analysis were used to characterize adverse reaction patterns, while multivariate logistic regression was employed to assess the influence of vaccine type and demographic factors.

Results: Inactivated, recombinant, and intramuscular Ad5 vectored vaccines commonly caused injection site pain, fatigue, headache, and pyrexia from the SOC of 'General disorders and administration site conditions.' Intranasal influenza-vectored vaccines mainly cause respiratory symptoms such as rhinorrhea and nasal congestion, while dry mouth and oropharyngeal pain from 'Gastrointestinal disorders' were primarily observed in aerosolized Ad5 vectored vaccines. Younger age (p < 0.001), female sex (p = 0.001), comorbidities (p < 0.001), and intramuscular Ad5 vectored vaccines (p < 0.001) were significantly associated with higher adverse reaction risks.

Conclusions: COVID-19 vaccines developed through different technological approaches have distinct adverse reaction profiles.

Background: Adolescents and adults who contract chickenpox are at a higher risk of severe complications. Vaccination with the varicella vaccine (VarV) effectively prevents chickenpox.

Research design and methods: In this phase III, single-center, randomized, double-blind, active-controlled trial, 1,200 healthy participants were randomly assigned in a 1:1 ratio to receive two doses of either the test vaccine or the active control vaccine. Varicella-zoster virus (VZV) antibody was detected before vaccination and 42 days after the two doses of vaccination.

Results: The lower limits of the 95% CI for the differences in seroconversion rates and geometric mean titer (GMT) ratios between the two groups were greater than their respective pre-set non-inferiority margins. The overall incidence of Adverse events (AEs) and adverse reactions (ARs) in the test group was significantly lower than those in the control group. Additionally, the incidence rates of swelling and fatigue were lower in the test group compared to the control group after vaccination.

Conclusions: The test freeze-dried live attenuated VarV demonstrated good immunogenicity and higher safety compared to the active control vaccine in healthy participants aged 13-55 years.

Clinical trials registration: www.clinicaltrials.gov identifier: NCT06592456.

Background: Respiratory infections like pneumococcal disease (PD), respiratory syncytial virus (RSV), influenza (Flu), and COVID-19 significantly impact Japan's aging population, imposing substantial health and economic burdens. Effective vaccines exist, yet uptake remains limited due to funding constraints and vaccine hesitancy. This study assessed the societal return on investment in adult respiratory vaccination programs to support informed policy decisions.

Research design & methods: We conducted a benefit-cost analysis using static cohort models and life tables to estimate benefit-cost ratios (BCRs) and societal net benefits (NBs), monetizing health impacts through the value of statistical life and cost-of-illness methods. Costs comprised vaccination program expenses. Scenario and sensitivity analyses explore coverage scenarios and parameter assumptions.

Results: Adult vaccination programs generated BCRs around 18:1 within 5 years and 20:1 over a lifetime. Lifetime NBs exceeded ¥113 trillion, preventing nearly three million hospitalizations and freeing millions of hospital bed-days, alongside avoiding over ¥100 billion in productivity losses. Expanding vaccine coverage significantly increased the NBs by > 30%, whereas reduced COVID-19 vaccine uptake notably diminished returns.

Conclusion: Japan's adult respiratory vaccination programs generate substantial socioeconomic returns, strengthening public health, healthcare resilience, and workforce productivity. Increasing uptake across the population can generate significantly higher NBs. Realizing these benefits requires addressing vaccine uptake barriers and enhancing public investment.

Background: CoronaVac (Sinovac) was initially effective against symptomatic COVID-19 and severe outcomes, but its performance against the immune-evasive Omicron variant remains uncertain. This study evaluated the effectiveness of CoronaVac against hospitalized COVID-19 among Filipino adults during the Omicron-dominant wave.

Research design and methods: We conducted a test-negative case-control study from November 2022 to November 2023 in three tertiary government hospitals in the Philippines. Adults hospitalized with acute respiratory illness (ARI) were enrolled. Cases tested positive for SARS-CoV-2 by RT-PCR; controls tested negative. Vaccination status was confirmed via vaccination cards or the national registry. Conditional logistic regression estimated vaccine effectiveness (VE). Genomic sequencing identified circulating variants.

Results: Among 2,365 participants, 165 (7.0%) were COVID-19 positive. In an age-matched analysis (104 cases, 408 controls), two CoronaVac doses provided 61.3% protection (95% CI: 5.3-84.2%) against critical illness. A heterologous booster conferred 65.9% protection against severe disease, 90.1% against critical illness, and 60.5% against death. Sequencing of 23/46 samples confirmed Omicron XBB-like variants.

Conclusion: Two doses of CoronaVac offered moderate protection against severe COVID-19. Heterologous boosters significantly improved protection, especially against critical illness and death, supporting ongoing booster campaigns after inactivated vaccine priming.

Introduction: Traditional live-attenuated or inactivated vaccines have limitations, including risks associated with uncontrolled replication, reduced immunogenicity, or production complexities. To address these issues, alternative platforms such as virus-like particles (VLPs) have been developed.

Areas covered: VLPs are self-assembling structures composed of viral proteins that mimic native viruses but are noninfectious. This review provides an overview of their structure, design and manufacture that make them an attractive platform for vaccine development. We then discuss the clinical development of some recently approved VLP vaccines and those widely used in immunization programs, summarizing the clinical trial data that underpins their efficacy and safety profiles. Additionally, we explore VLP vaccines in late-stage clinical development for respiratory syncytial virus and human metapneumovirus.

Expert opinion: VLPs are a versatile and promising platform for vaccine development. Their ability to mimic native viruses while eliminating the risks associated with live vaccines positions them as an attractive platform for vaccine design. Currently approved VLP vaccines demonstrate that they can provide effective protection against a wide range of diseases. Advances in VLP design and production are likely to lead to highly effective vaccines, significantly contributing to global immunization efforts.

Introduction: Non-survey-based data sources (e.g. electronic health records, administrative claims) have been used to estimate vaccination coverage among US adults. However, these data sources were not collected for research or surveillance purposes and may have substantial limitations. The objectives of this narrative review were to: 1) identify published studies that used non-survey-based data sources to estimate adult vaccination coverage for one or more routinely recommended vaccines; and 2) summarize the strengths and limitations of these data sources for coverage assessments.

Areas covered: Thirty-four publications derived from 9 data sources were reviewed: 16 publications were in a general population (i.e. defined by age), 12 were among pregnant women, and 6 were among individuals with chronic health conditions. While several data sources used continuous health insurance enrollment to define the study population, doing so limited generalizability to stably insured populations. Methods for obtaining race and ethnicity data were complex and potentially subject to bias. None of the reviewed studies presented any formal assessment of vaccine data validity.

Expert opinion: While multiple non-survey-based data sources have been used to assess adult vaccination coverage in the United States, important limitations exist, including related to generalizability, data validity, and risk of bias.