Jul 2026· Infectious Disease and Therapy· Vol 15, pp. 2545 - 2560· 0 citations· 44 references
Medicine
TL;DR
Evaluating current influenza vaccination coverage and identifying factors that may influence whether adults choose to be vaccinated suggests that efforts to advance equity may benefit from addressing structural barriers, such as expanding insurance coverage, workplace vaccination programs, and targeted outreach to underserved populations.
Abstract
Despite longstanding recommendations for universal adult influenza vaccination, coverage remains suboptimal in the United States (U.S.). The objective of this study is to examine current influenza vaccination coverage and identify demographic, socioeconomic, and geographic disparities in vaccination among U.S. adults. Cross-sectional analysis of 2023 Behavioral Risk Factor Surveillance System data from 402,005 adults across 52 states/territories. Survey-weighted logistic regression models assessed independent predictors of self-reported influenza vaccination in the past twelve months, including demographics, socioeconomic factors, healthcare access, and health status. Overall vaccination coverage was 42.2% (95% CI 42.0–42.4%), well below the Healthy People 2030 target of 70%. Coverage increased markedly with age, from 29.2% among 18–24 year-olds to 66.9% among those ≥ 80 years of age. Women had higher coverage than men (45.4% vs. 38.7%, p < 0.001). Strong socioeconomic gradients emerged: coverage among college graduates (54.3%) exceeded that of those with less than a high school education (32.6%) and those earning ≥ $200,000 (53.5%) exceeded those earning < $15,000 (34.4%). Insurance status showed the largest disparity—45.1% of insured versus 16.2% of uninsured adults were vaccinated. Geographic variation was substantial, ranging from 19.1% in the Virgin Islands to 56.6% in Massachusetts. In multivariable analysis, the strongest predictors were advanced age (≥ 80 years: adjusted OR = 3.51, 95% CI 3.18–3.87), insurance coverage (adjusted OR = 1.74, 95% CI 1.57–1.93), and recent healthcare engagement (checkup within past year; adjusted OR = 1.62, 95% CI 1.53–1.73). Influenza vaccination coverage remains far below national targets, with pronounced disparities across age, socioeconomic status, insurance coverage, and geography. These findings suggest that efforts to advance equity may benefit from addressing structural barriers, such as expanding insurance coverage, workplace vaccination programs, and targeted outreach to underserved populations; because the data are observational, these represent potential implications rather than conclusions about causal effects. Influenza (flu) is a highly contagious respiratory illness caused by the influenza virus. Annual influenza vaccination has been shown to reduce the incidence of influenza as well as its related complications such as hospitalization, respiratory failure, and even death. Despite longstanding recommendations for universal adult influenza vaccination, the Centers for Disease Control and Prevention (CDC) estimates that only about half of U.S. adults receive the vaccine on an annual basis. The goal of this project was to evaluate current influenza vaccination coverage and identify factors that may influence whether adults choose to be vaccinated. We performed an analysis of data from the CDC's Behavioral Risk Factor Surveillance System (BRFSS), the nation's largest continuously conducted health survey system. The data included telephonic survey responses from 402,005 adults across 52 states/territories. The survey asks respondents to provide their age, sex, race/ethnicity, education level, household income, health insurance status, self-rated health status, and influenza vaccination status. Main results of the analysis include: overall only 42% of respondents reported receiving the influenza vaccine. Coverage increased markedly with age, from 29% among 18–24 year-olds to 67% among those 80 years of age or older. Other strong predictors of receiving influenza vaccination included having a higher education level, higher household income, and health insurance. These data point to the need for public health initiatives that expand access of the influenza vaccine to young adults, those with limited education and/or income, as well as uninsured adults.
Targeted communication, such as risk-stacking to improve risk-awareness, harmonized eligibility criteria, and co-administration, may help overcome remaining vaccination barriers in high-risk individuals.
Lucas Grape, Wilma Persson, Adam Sergejev et al.· Human Vaccines & Immunothera...· 0 citations
Targeted communication, such as risk-stacking to improve risk-awareness, harmonized eligibility criteria, and co-administration, may help overcome remaining vaccination barriers in high-risk individuals.
Lucas Grape, Wilma Persson, Adam Sergejev et al.· 0 citations
BACKGROUND
The extent to which influenza vaccination may temper disease remains uncertain. We compared symptoms between influenza vaccinated and unvaccinated ambulatory persons with influenza.
METHODS
We conducted household transmission studies across multiple US sites during consecutive influenza seasons from 2017-2018 through 2022-2023 (excluding 2020-2021 season with minimal influenza activity). We collected daily symptom diaries and respiratory specimens. Three scores were calculated, varying weights on specific symptoms: 1) influenza-like illness (ILI); 2) lower respiratory; and 3) all symptoms. For each score, we examined the daily mean score between those vaccinated and unvaccinated against influenza using weighted multivariable linear mixed effects and frailty models.
RESULTS
Study included 869 children (41% vaccinated, 47% female, 58% white, non-Hispanic) and 653 adults (42% vaccinated, 65% female, 72% white, non-Hispanic) with laboratory-confirmed influenza. In multivariable analyses, the mean difference in the daily ILI score was -0.16 (95% CI: -0.32, -0.01) between vaccinated and unvaccinated children and -0.18 (95% CI: -0.34, -0.01) for the lower respiratory score. There was no significant difference among adults. Influenza vaccination was not associated with time to symptom alleviation among children. However, ILI symptom alleviation occurred earlier among vaccinated (HR: 1.30, 95% CI: 1.04, 1.62) adults.
CONCLUSION
Ambulatory children with influenza who were vaccinated experienced less ILI symptom burden compared to those who were not vaccinated against influenza, but vaccination was not associated with symptom duration. Conversely, among ambulatory adults with influenza, vaccination and symptom burden were not associated, but vaccination was associated with faster alleviation of ILI symptoms.
Amanda C Howa, Yuwei Zhu, T. McGonigle et al.· Clinical Infectious Diseases· 0 citations
BACKGROUND
Influenza vaccination coverage in France remains suboptimal, with variability across population groups. We assessed demographic and behavioral determinants of influenza vaccination in the post-COVID-19 period among a primary care population in the Haute-Vienne department (Nouvelle-Aquitaine, France).
METHODS
We conducted a cross-sectional survey using an anonymous, self-administered questionnaire distributed to adults attending five general-practice sites between May and July 2023. The primary outcome was receipt of the 2022-2023 influenza vaccine. Candidate determinants included age, sex, municipality size, socio-professional category, eligibility criteria (age ≥ 65 years, healthcare-worker status, chronic conditions, or pregnancy), prior influenza vaccination, number of COVID-19 vaccine doses received, and self-reported history of influenza infection. Associations were examined using chi-square tests, Cochran-Armitage trend tests, and univariate logistic regression. Two multivariable logistic regression models were then constructed: a demographic model including age, sex, municipality size, socio-professional category, and the presence of any comorbidity or pregnancy, and a behavioral model including prior influenza vaccination and COVID-19 vaccination status (≥ 3 doses vs. ≤ 2 doses). Adjusted results were expressed as adjusted odds ratios (aOR) with 95% confidence intervals (95% CI).
RESULTS
Among the 800 questionnaires distributed, 432 were returned (participation rate: 54%). Overall, 75.9% of participants met at least one eligibility criterion for influenza vaccination. Influenza vaccination coverage for the 2022-2023 season was 58.3% and differed by municipality size (38.8% in areas with fewer than 5,000 inhabitants; 59.2% in those with 5,000-10,000; and 64.3% in those with more than 10,000, p = 0.0003) and increased with the regularity of prior influenza vaccination (6.7% among never vaccinated, 55.9% among occasional, and 96.6% among annually vaccinated, p < 0.0001). Coverage was also associated with the number of COVID-19 vaccine doses received (p < 0.0001). In the demographic model, age ≥ 65 years was associated with higher vaccination uptake (aOR 8.55, 95% CI 1.88-61.73, p = 0.012), whereas other demographic variables were not independently associated with vaccination uptake. In the behavioral model, prior influenza vaccination was strongly associated with vaccination uptake (aOR 16.20, 95% CI 7.21-36.41 for occasional vs. never and aOR 331.21, 95% CI 122.57-894.99 for annual vs. never; both p < 0.001). Receipt of ≥ 3 COVID-19 vaccine doses was also independently associated with vaccination uptake (aOR 2.64, 95% CI 1.01-6.89, p = 0.047).
CONCLUSIONS
In this primary care survey, influenza vaccination during the 2022-2023 season was primarily associated with prior influenza vaccination history, suggesting persistence of vaccination practices over time. Age ≥ 65 years and receipt of ≥ 3 COVID-19 vaccine doses were also independently associated with vaccination uptake, although to a lesser extent. Targeted strategies that reinforce continuity (annual reminders, vaccination offers during routine visits, and co-administration options) and encourage initiation among previously unvaccinated adults could help improve coverage.
TRIAL REGISTRATION
Not applicable.
S. Mafi, A. Billo, M. Durieux et al.· BMC Public Health· 0 citations
Seasonal influenza remains a leading cause of preventable morbidity and mortality despite decades of widespread vaccination. Annual reformulation of the influenza vaccine and variable uptake rates hinder consistent population-level protection. Understanding how vaccination coverage, population density, and susceptibility interact is essential to refining prevention strategies.
Using published national and state-level data from 1980—2019, we analyzed influenza-associated mortality across age groups and comorbidity profiles relative to annual vaccination coverage. We further evaluated 2017 influenza mortality in relation to population density and vaccine availability to assess geographic and demographic trends.
Despite increasing vaccination rates from 1980 to 2019, influenza-related mortality among adults ≥65 years remained unchanged. No state or national herd immunity threshold was reached during this period. Vaccine supply growth lagged behind U.S. population expansion, limiting coverage sufficient for community-level protection. In 2017, the most populous states exhibited the highest influenza-related mortality burden; however, within these states, city density did not correlate with mortality rates. Influenza deaths were concentrated where susceptible populations resided, regardless of urban or rural classification.
Our findings indicate that current annual influenza vaccination strategies have not achieved herd immunity or reduced mortality among the most vulnerable populations. To substantially decrease influenza-related deaths, vaccination efforts must prioritize achieving herd immunity within the nation’s most populous states, where transmission potential and susceptible populations are greatest.
N/A
Vaccines and Immunotherapy (VAC)
M. Premenko-Lanier, Liliya Parkman, Jared Quesada· Journal of Immunology· 0 citations
Background Healthcare workers (HCWs) are prioritised to receive influenza vaccine annually in Georgia. We aimed to identify factors associated with influenza vaccine uptake among Georgian HCWs. Methods We used self-reported influenza vaccination data for three influenza seasons (2021–2024) and 2023 survey data on attitudes towards influenza from a prospective cohort of HCWs in six hospitals in Georgia. HCWs who received influenza vaccine in at least one season were compared with those who were not vaccinated in any season. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were calculated using multivariable logistic regression to identify factors associated with vaccination uptake. Findings Of 403 participants, the median age was 46 (IQR 36–54), 364 (90%) were female, 168 (42%) were nurses or midwives, 85 (21%) were support staff, 75 (19%) were doctors, and 75 (19%) were other staff. Overall, 289 (72%) received influenza vaccine in at least one season, while 114 (28%) did not receive it in any season. Multivariable analysis showed no differences in vaccine uptake by sex or occupation. HCWs ≥ 30 years were more likely to be vaccinated, with those aged 40–49 having the highest odds (aOR 2.67, 95% CI 1.09–6.59). HCWs who did not believe the vaccine was safe (aOR 0.27, 95% CI 0.11–0.68), those who doubted its effectiveness (aOR 0.36, 95% CI 0.14–0.89), and HCWs at Hospital B (aOR 0.06, 95% CI 0.02–0.23) were less likely to be vaccinated. Conclusions Georgian HCWs who questioned influenza vaccine safety and effectiveness, and those at one hospital, had lower odds of vaccination over three years, whereas older HCWs were more likely to be vaccinated. Future campaigns to promote influenza vaccination among HCWs should address safety and effectiveness concerns and target demographic disparities.
O. Artemchuk, Giorgi Chakhunashvili, Iris Finci et al.· PLoS ONE· 0 citations
