Jul 2026· American Journal of Health Promotion· pp.
8901171261468529
· 0 citations· 33 references
Medicine
TL;DR
Individuals with a history of preventive care, such as attending at least one non-emergency medical visit in the past year, receiving either the pneumococcal or influenza vaccine within the past year, strongly predicted COVID-19 vaccine acceptance.
Abstract
PurposeCOVID-19 devastated communities globally, with the United States leading in fatalities despite extensive control efforts. In 2021, COVID-19 vaccines emerged as the most promising solution, with an efficacy rate exceeding 95% after full vaccination. However, herd immunity remains an elusive target with only 70% of the U.S. population fully vaccinated. This study investigates whether prior vaccination and medical history significantly predict COVID-19 vaccine acceptance and uptake.DesignUsing data collected from the 66th largest U.S. city after the widespread deployment of COVID-19 vaccines and boosters, we employed logistic regression to test whether an individual's history of vaccination and prior medical engagement positively influence COVID-19 vaccine-related decisions.SettingCross-sectional U.S. survey from July-October 2022 (N = 397) and November 2023-February 2024 (N = 429).SubjectsAdult Residents of the City of Newark, New Jersey (Aged 18+).MeasuresNewark Community Health Survey (2022, 2023).ResultsIndividuals with a history of preventive care, such as attending at least one non-emergency medical visit in the past year, receiving either the pneumococcal or influenza vaccine within the past year, strongly predicted COVID-19 vaccine acceptance. These predictors also demonstrated a strong positive association with the completion of the primary vaccine series and a higher overall total vaccine uptake.ConclusionFuture vaccine campaigns should prioritize "low engagement" populations who lack both recent routine medical visits and a history of previous vaccinations.
Vaccine hesitancy has long been recognized as a global health concern and has become an even greater challenge during and after the COVID-19 pandemic. Although extensive research has examined hesitancy toward COVID-19, how the general population would respond to vaccination in a future pandemic remains unclear. Furthermore, little is known about the conditions that may reduce hesitancy. In this study, we conducted a nationwide internet survey in Japan in 2024–2025 involving 28,000 participants to assess vaccination intentions in a hypothetical future pandemic, identify factors associated with vaccine hesitancy, and examine conditions that may increase willingness to be vaccinated. We analyzed associations between individual characteristics and vaccination intention using logistic regression and explored heterogeneity in prioritized factors to determine vaccination intention using unsupervised clustering analysis. We found that only 53.1% of respondents reported intending to be vaccinated in a future pandemic—a marked decline from observed COVID-19 vaccination coverage. Notably, 35.8% of individuals who were vaccinated during the COVID-19 pandemic expressed hesitancy. Vaccination intention was lower among adults aged 20–40 years, women, individuals with lower income or educational attainment, and those endorsing misinformation or conspiracy statements. Cluster analysis identified eight distinct groups with heterogeneous priority structures. Free vaccination and evidence from clinical trials were prioritized across all clusters, whereas the prioritization of trust in authorities, social influence, domestic vaccine production, and convenience varied substantially across clusters. Public intentions to vaccinate in a future pandemic are shaped by diverse perspectives and values. Tailored strategies and risk communication approaches that address these heterogeneous concerns may be critical to strengthening preparedness for future pandemics.
J. Kawasaki, Masakaze Hamada, Masaki Machida et al.· npj Vaccines· 0 citations
Established determinants of health in the elderly help guide routines for indicated vaccine administration, while unmeasured frailty may limit vaccine access. We evaluate the performance of the 2024-2025 COVID-19 vaccine adapted to the Omicron JN.1 lineage in a Swedish population aged ≥65 years (N = 245 696). Vaccine effectiveness (VE) on COVID-19-related hospitalization and a negative control outcome (NCO; all-cause mortality) are assessed in various cohorts between October 1, 2024 to March 31, 2025. The VE was 75% (95% CI 70%–79%) overall, and 84% (95% CI 80%–87%) and 65% (95% CI 34%–82%) in individuals with and without vaccination with the prior updated COVID-19 vaccine in 2023-2024, respectively. The NCO in individuals exposed to the study vaccine in 2024-2025 was half of that seen in those not exposed to the vaccine (HR 0.43 [95% CI 0.40–0.45]). Removing individuals hospitalized with COVID-19 from this population did not change the difference in NCO (HR 0.43 [95% CI 0.41-0.46]). These findings suggest the presence of selection effects arising from under-provision of health services to elderly individuals with frailty. The healthy vaccinee effect should be considered in observational studies of the effectiveness of updated COVID-19 vaccines in elderly populations. This Swedish population study reveals that healthy vaccinee bias inflates estimates of the effectiveness of updated COVID-19 vaccines in adults aged 65 years or older, highlighting the need to account for frailty and overall health status.
Johan Lyth, A. Spreco, J. Hinkula et al.· Nature Communications· 0 citations
Health status influences COVID-19 vaccine uptake, with vaccinated individuals generally being healthier than unvaccinated ones. This difference may impact vaccine effectiveness estimates. This study investigated the magnitude of this healthy vaccinee effect on effectiveness estimates. Three national, matched, retrospective cohort studies were conducted on Qatar’s population from February 5, 2020-May 14, 2024, to estimate effectiveness of primary-series and booster vaccinations and of natural infection against infection and severe, critical, or fatal COVID-19. The studies explored three matching scenarios by coexisting conditions, reflecting varying levels of health-status imbalance between vaccinated and unvaccinated individuals. Each matched cohort included >810,000 individuals in the primary-series analysis, >330,000 in the booster analysis, and >730,000 in the natural-infection analysis. Effectiveness was derived from adjusted hazard ratios estimated using Cox regression models. Here we show that vaccine effectiveness against infection and severe, critical, or fatal COVID-19 remained consistent across matching strategies, despite differences in non-COVID-19 mortality. For example, primary-series effectiveness against severe COVID-19 was 96.3% (95% CI: 94.5–97.5) when matching by exact coexisting conditions, 94.2% (95% CI: 92.5–95.6) when matching by number of coexisting conditions, and 94.0% (95% CI: 92.3–95.3) with no matching by coexisting conditions. Similar results were observed in subgroup analyses by follow-up duration and among clinically vulnerable individuals. Comparable findings applied to natural infection’s effectiveness against reinfection and severe COVID-19. Health status differences between vaccinated and unvaccinated individuals did not introduce measurable bias in real-world vaccine effectiveness estimates. Findings highlight the importance of using specific outcomes in vaccine effectiveness studies.
H. Chemaitelly, H. Ayoub, Peter V. Coyle et al.· Communications Health· 0 citations
COVID-19 vaccination helped change the course of the pandemic and remains critical for protecting high-risk groups. We analyzed data submitted to WHO to describe COVID-19 vaccination coverage during the emergency period from 2021-2023 and annual uptake in 2024, the first post-emergency calendar year after the Public Health Emergency of International Concern designation was lifted. By end-2023, global complete primary series coverage reached 65% in the total population, 82% among older adults, and 91% among health and care workers (HCWs), across reporting countries. Booster coverage was lower, at 33%, 60%, and 69%, respectively. Across indicators, disparities by country income group and region emerged early and persisted through 2024. In 2024, vaccination of older adults and HCWs was limited and heterogeneous. These findings underscore the need for stronger, sustainably financed adult immunization platforms and associated monitoring systems to enhance life-course vaccination benefits and to support future outbreak, epidemic, and pandemic responses.
D. Brooks, A. Germann, L. Craw et al.· medRxiv· 0 citations
We examined whether COVID-19 vaccine type was associated with national full-vaccination coverage using 1034 country–vaccine entries from 195 countries derived from World Health Organization data. In a country-level analysis adjusting for World Bank income group, WHO region, and the number of vaccine products per country, neither mRNA vaccine availability (p = 0.051) nor the proportion of mRNA vaccines in a country’s portfolio (p = 0.164) was significantly associated with coverage. Vaccine-related variables added only one percentage point to the explained variance beyond structural factors (ΔR2=0.011). Unadjusted exploratory analyses showed that some vaccine products were more frequently recorded in high-coverage country contexts, but these patterns were substantially attenuated after adjustment for structural covariates. The apparent link between vaccine category and coverage largely reflected differences in economic capacity, geographic region, and deployment context rather than vaccine category itself.
W. Al-Zyoud, D. Erekat, Mohammad Abudayah· PLOS Global Public Health· 0 citations
Background/Objectives We evaluated the impact of the COVID-19 adolescent vaccination in England at two different epidemic points: the autumn (August-November) 2021, in the presence of a large Omicron epidemic wave, and the autumn (August-November) 2022, when the subsequent Omicron epidemic was at an endemic stage. Methods Using the Covasim SARS-CoV-2 model for England, under varying vaccine uptake and onset time, we evaluated the impact of a)vaccinating 18+ only versus additional 12+ vaccination from the autumn 2021; and b)the current immunisation strategy at the time versus additional 12+ vaccination from September 2022, projecting the number of new daily SARS-CoV-2 infections, hospitalisations and deaths. Results In presence of the BA.1 Omicron wave in late 2021, the expanded adolescent vaccination averted ~3,000,000 cases across all-ages, ~1,010,000 SARS-CoV-2 infections in the period 2-6 months from vaccine onset in the vaccinated cohort. During the Omicron waves in 2022, additional adolescents vaccination did not significantly reduce the COVID-19 burden in the entire population, nor within the vaccinated cohort. Conclusions Our findings highlight that adolescent vaccination impact depends on the timing/speed of implementation, other present intervention strategies, and the status of the epidemic at the time and it should not be considered as a stand-alone immunisation strategy.
A. Fairweather, B. Swallow, R. Stuart et al.· medRxiv· 0 citations
