Influenza Vaccination In Adults Research Articles

Cost-effectiveness of the adjuvanted quadrivalent influenza vaccine for older adults in South Korea

ABSTRACT South Korea’s National Immunization Program administers the quadrivalent influenza vaccine (QIV) to manage seasonal influenza, with a particular focus on the elderly. After reviewing the safety and immune response triggered by the adjuvanted QIV (aQIV) in individuals aged 65 and older, the Ministry of Food and Drug Safety in Korea approved its use. However, the extensive impact of aQIV on public health is yet to be fully understood. This study assessed the cost-effectiveness of replacing QIV with aQIV in South Korean adults aged 65 years and older. A dynamic transmission model, calibrated with national influenza data, was applied to compare the influence of aQIV and QIV on older adults and the broader population throughout a single influenza season. This study considered both the direct and indirect effects of vaccination on the elderly. We derived the incremental cost-effectiveness ratios (ICERs) from quality-adjusted life-years (QALYs) and costs incurred, validated through a probabilistic sensitivity analysis with 5,000 simulations. Findings suggest that transitioning to aQIV from QIV in the elderly would be cost-effective, particularly if aQIV’s efficacy reaches or exceeds 56.1%. With an ICER of $29,267/QALY, considerably lower than the $34,998/QALY willingness-to-pay threshold, aQIV presents as a cost-effective option. Thus, implementing aQIV with at least 56.1% efficacy is beneficial from both financial and public health perspectives in mitigating seasonal influenza in South Korea.

Effect of a Non-pharmacological Intervention on Vaccine-related Pain: Randomized Clinical Trial

BackgroundAcute pain during vaccine administration is an expected event; however, some strategies, such as the use of high frequency vibration devices associated with cryotherapy, may minimize it. AimEvaluate the effect of high frequency vibration associated with cryotherapy on the level of pain related to the administration of influenza vaccine by intramuscular route in adults. MethodA randomized clinical trial was conducted with 350 adults who received the influenza vaccine. Participants allocated to the intervention group used a high-frequency vibration device associated with cryotherapy during vaccination, and those in the control group administered the vaccine according to the service routine. ResultsMean self-reported pain after vaccination of participants who used the device was lower (1.5 ±1.7) when compared to those who did not use it (1.9 ±1.9) (p = .041). There was an association of higher levels of pain after vaccination with participants in the control group (p = .011), females (p = .042), with higher level of pain expected with vaccination (p < .001) and higher level of anxiety before (p < .001) and after vaccination (p = .001). ConclusionsThe use of high frequency vibration associated with cryotherapy has been shown to be a viable non-pharmacological intervention for the reduction of pain associated with influenza vaccination in adults.

Changes in depressive symptoms and antibody production following influenza vaccination in adolescents and adults

ObjectivePsychological distress has been associated with dampened antibody production following vaccination. Questions remain, however, about whether psychological distress influences vaccine response uniformly across the lifespan, and whether changes in distress result in changes in antibody production across the same period. MethodsParticipants (N = 148; Mage = 32.2 years, SD = 19.7, range = 12–80 years) took part in consecutive vaccine studies during the 2017–2018 and 2018–2019 influenza seasons. Each influenza season, they reported on their depressive symptoms, provided blood samples, and received the standard influenza vaccine. Participants then provided a second blood sample one month later. Antibody titers were examined pre- and post-vaccination. ResultsAnalyses examined both within-season and across-season effects of depressive symptoms, age, and their interaction on vaccine response. Within-season analyses revealed that age predicted antibody response during both seasons (2017–2018 and 2018–2019). Neither depressive symptoms nor the interaction with age were associated with antibody response to vaccination within either season. Across the two seasons, age significantly moderated the association between change in depressive symptoms and change in antibody production. For people who were 48 or older, increases in depressive symptoms across the two seasons were associated with a less robust response to the vaccine in the second season relative to the first season. For people younger than 48, changes in depressive symptoms were not significantly related to changes in antibody production. ConclusionsThese findings highlight the important role of mental health for older adults’ vaccine response, which could have clinical relevance for protection against disease.

Estimating the Undetected Burden of Respiratory Syncytial Virus Hospitalizations in Adults Through Capture-Recapture Methods.

Traditional surveillance systems may underestimate the burden caused by respiratory syncytial virus (RSV). Capture-recapture methods provide alternatives for estimating the number of RSV-related hospitalizations in a population. Capture-recapture methods were used to estimate the number of RSV-related hospitalizations in adults in Middle Tennessee from two independent hospitalization surveillance systems during consecutive respiratory seasons from 2016-2017 to 2019-2020. Data from the Hospitalized Adult Influenza Vaccine Effectiveness Network (HAIVEN) and the Emerging Infections Program (EIP) were used. Annual RSV hospitalization rates were calculated using the capture-recapture estimates weighted by hospitals' market share divided by the corresponding census population. Using capture-recapture methods, the estimated overall adult hospitalization rates varied from 8.3 (95% CI: 5.9-15.4) RSV-related hospitalizations per 10,000 persons during the 2016-2017 season to 28.4 (95% CI: 18.2-59.0) hospitalizations per 10,000 persons in the 2019-2020 season. The proportion of hospitalizations that HAIVEN determined ranged from 8.7% to 36.7% of the total capture-recapture estimated hospitalization, whereas EIP detected 23.5% to 52.7% of the total capture-recapture estimated hospitalizations. Capture-recapture estimates showed that individual traditional surveillance systems underestimated the hospitalization burden in adults. Using capture-recapture allows for a more comprehensive estimate of RSV hospitalizations.

Immunogenicity and safety of concomitant administration of recombinant COVID-19 vaccine and quadrivalent inactivated influenza vaccine in Chinese adults: An open-label, randomized, controlled trial

ABSTRACT The immunogenicity and safety of the concomitant administration of recombinant COVID-19 vaccine and quadrivalent inactivated influenza vaccine (Split Virion) (QIIV) in Chinese adults are unclear. In this open-label, randomized controlled trial, participants aged ≥ 18 years were recruited. Eligible healthy adults were randomly assigned (1:1) to receive QIIV at the same time as the first dose of COVID-19 vaccine (simultaneous-group) or 14 days after the second dose of COVID-19 vaccine (non-simultaneous-group). The primary outcome was to compare the difference in immunogenicity of QIIV (H1N1, H3N2, Yamagata, and Victoria) between the two groups. A total of 299 participants were enrolled, 149 in the simultaneous-group and 150 in the non-simultaneous-group. There were no significant differences in geometric mean titer (GMT) [H1N1: 386.4 (95%CI: 299.2–499.0) vs. 497.4 (95%CI: 377.5–655.3); H3N2: 66.9 (95%CI: 56.1–79.8) vs. 81.4 (95%CI: 67.9–97.5); Yamagata: 95.6 (95%CI: 79.0–115.8) vs. 74.3 (95%CI: 58.6–94.0); and Victoria: 48.5 (95%CI: 37.6–62.6) vs. 65.8 (95%CI: 49.0–88.4)] and seroconversion rate (H1N1: 87.5% vs. 90.1%; H3N2: 58.1% vs. 62.0%; Yamagata: 75.0% vs. 64.5%; and Victoria: 55.1% vs. 62.8%) of QIIV antibodies between the simultaneous and non-simultaneous groups. For the seroprotection rate of QIIV antibodies, a higher seroprotection rate of Yamagata antibody was observed only in the simultaneous-group than in the non-simultaneous-group [86.0% vs. 76.0%, p = .040]. In addition, no significant difference in adverse events was observed between the two groups (14.2% vs. 23.5%, p = .053). In conclusion, no immune interference or safety concerns were found for concomitant administration of COVID-19 vaccine with QIIV in adults aged ≥ 18 years.

Trivalent and quadrivalent seasonal influenza vaccine in adults aged 60 and older: a systematic review and network meta-analysis

ObjectivesTo compare the efficacy of influenza vaccines of any valency for adults 60 years and older.Design and settingSystematic review with network meta-analysis (NMA) of randomised controlled trials (RCTs). MEDLINE, EMBASE,...

Immunogenicity of Enhanced Influenza Vaccines Against Mismatched Influenza Strains in Older Adults: A Review of Randomized Controlled Trials.

Antigenic drift is a major driver of viral evolution and a primary reason why influenza vaccines must be reformulated annually. Mismatch between vaccine and circulating viral strains negatively affects vaccine effectiveness and often contributes to higher rates of influenza-related hospitalizations and deaths, particularly in years dominated by A(H3N2). Several countries recommend enhanced influenza vaccines for older adults, who are at the highest risk of severe influenza complications and mortality. The immunogenicity of enhanced vaccines against heterologous A(H3N2) strains has been examined in nine studies to date. In six studies, an enhanced, licensed MF59-adjuvanted trivalent inactivated influenza vaccine (aIIV3) consistently increased heterologous antibody titers relative to standard influenza vaccine, with evidence of a broad heterologous immune response across multiple genetic clades. In one study, licensed high-dose trivalent inactivated influenza vaccine (HD-IIV3) also induced higher heterologous antibody titers than standard influenza vaccine. In a study comparing a higher dose licensed quadrivalent recombinant influenza vaccine (RIV4) with HD-IIV3 and aIIV3, no significant differences in antibody titers against a heterologous strain were observed, although seroconversion rates were higher with RIV4 versus comparators. With the unmet medical need for improved influenza vaccines, the paucity of studies especially with enhanced vaccines covering mismatched strains highlights a need for further investigation of cross-protection in older adults.

Analysis of Attitudes and Practices towards the Influenza Vaccine in High-Risk Adults in Poland.

This study aimed to understand Poles' attitudes and beliefs towards influenza vaccinations in the flu season of 2022-2023, especially among individuals at risk of flu complications. The cross-sectional survey-based study was carried out on a sample of 810 respondents. The questionnaire was disseminated electronically using social media and e-mail. The majority of respondents (71%) could identify "high-risk groups" recommended for influenza vaccination, and 52.01% of respondents reported receiving influenza vaccination at some point in the past, with 32.12% receiving it in the 2022-2023 flu season and 41.09% in the 2021-2022 season. The majority of respondents declaring acceptance of the vaccine for the 2022-2023 season were in the high-risk group. Only 17.28% of respondents declared receiving both influenza and SARS-CoV-2 vaccines in the 2022-2023 season, with the vast majority being respondents from the "high-risk group" (p < 0.0001). Only 26.12% of respondents declared their intention to continue influenza vaccination in the future. Of those expressing the intention to get vaccinated against the influenza virus in future seasons, 46.79% were from the "high-risk group" (p = 0.0087). Results suggest the need for further interaction and education with healthcare providers and targeted informational efforts for at-risk groups regarding the benefits of flu vaccination.

Podcast: Need for Quality Evidence for Decision-Making on Seasonal Influenza Vaccines.

Seasonal influenza is usually considered an acute respiratory infection with a full recovery within a week. In addition to the traditional outcomes, there is now evidence of indirect effects in terms of neurological and functional complications. Major organ systems can be affected, underlining the need for preventative measures against infection. The aim of this podcast, featuring Dr. Ann Falsey, Dr. Stefania Maggi, and Dr. Tor Biering-Sørensen, is to outline influenza complications beyond acute respiratory disease, as well as discussing the need for quality of evidence when evaluating influenza vaccines. Assessing the benefits of vaccination can be challenging. To ensure a high quality of evidence, the innovative randomization of patients within the study design to avoid bias and the assessment of additional outcomes beyond immunogenicity as well as the inclusion of a broad population-including frail or vulnerable individuals-are essential. Studies leveraging nationwide registries such as the DANFLU-2 trial in Denmark highlight the advantages of a digitalized healthcare system for conducting large-scale randomized trials. Furthermore, large-scale trials such as the Gravenstein study have supplied a sizable body of evidence supporting the use of high-dose influenza vaccine in older adults. In conclusion, achieving a high quality of evidence is key for decision-making on seasonal influenza vaccines.

Strategies to increase the coverage of influenza and pneumonia vaccination in older adults: a systematic review and network meta-analysis.

It is urgent to implement interventions to increase vaccination rates of influenza/pneumonia vaccines in older adults, yet the effectiveness of different intervention strategies has not been thoroughly evaluated. We aimed to assess the effectiveness of intervention strategies for increasing the coverage of influenza/pneumonia vaccination in older adults. PubMed, Web of Science, Cochrane Library, Embase, China Biology Medicine disc, China National Knowledge Infrastructure and Wanfang were searched from 1 January 2000 to 1 October 2022. RCTs that assessed any intervention strategies for increasing influenza/pneumonia vaccination coverage or willingness in older adults were included. A series of random-effects network meta-analysis was conducted by using frequentist frameworks. Twenty-two RCTs involving 385,182 older participants were eligible for further analysis. Eight types of intervention strategies were evaluated. Compared with routine notification, health education (odds ratio [OR], 1.85 [95%CI, 1.19 to 2.88]), centralised reminder (OR, 1.63 [95%CI, 1.07 to 2.47]), health education + onsite vaccination (OR, 2.89 [95%CI, 1.30 to 6.39]), and health education + centralised reminder + onsite vaccination (OR, 20.76 [95%CI, 7.33 to 58.74]) could effectively improve the vaccination rate. The evidence grade was low or very low due to the substantial heterogeneity among studies. Our findings suggest that health education + centralised reminder + onsite vaccination may potentially be an effective strategy regardless of cost, but the evidence level was low. More rigorous trials are needed to identify the association between strategies and vaccination rates among older adults and to integrate such evidence into clinical care to improve vaccination rates.

County-Level Factors Associated With Influenza and COVID-19 Vaccination in Indiana, 2020‒2022.

Objectives. To assess COVID-19 and influenza vaccination rates across Indiana's 92 counties and identify county-level factors associated with vaccination. Methods. We analyzed county-level data on adult COVID-19 vaccination from the Indiana vaccine registry and 2021 adult influenza vaccination from the Centers for Disease Control and Prevention. We used multiple linear regression (MLR) to determine county-level predictors of vaccinations. Results. COVID-19 vaccination ranged from 31.2% to 87.6% (mean = 58.0%); influenza vaccination ranged from 33.7% to 53.1% (mean = 42.9%). In MLR, COVID-19 vaccination was significantly associated with primary care providers per capita (b = 0.04; 95% confidence interval [CI] = 0.02, 0.05), median household income (b = 0.23; 95% CI = 0.12, 0.34), percentage Medicare enrollees with a mammogram (b = 0.29; 95% CI = 0.08, 0.51), percentage uninsured (b = -1.22; 95% CI = -1.57, -0.87), percentage African American (b = 0.31; 95% CI = 0.19, 0.42), percentage female (b = -0.97; 95% CI = -1.79, ‒0.15), and percentage who smoke (b = -0.75; 95% CI = -1.26, -0.23). Influenza vaccination was significantly associated with percentage uninsured (b = 0.71; 95% CI = 0.22, 1.21), percentage African American (b = -0.07; 95% CI = -0.13, -0.01), percentage Hispanic (b = -0.28; 95% CI = -0.40, -0.17), percentage who smoke (b = -0.85; 95% CI = -1.06, -0.64), and percentage who completed high school (b = 0.54; 95% CI = 0.21, 0.87). The MLR models explained 86.7% (COVID-19) and 70.2% (influenza) of the variance. Conclusions. Factors associated with COVID-19 and influenza vaccinations varied. Variables reflecting access to care (e.g., insurance) and higher risk of severe disease (e.g., smoking) are notable. Programs to improve access and target high-risk populations may improve vaccination rates. (Am J Public Health. 2024;114(4):415-423. https://doi.org/10.2105/AJPH.2023.307553).

Immunogenicity, Reactogenicity, and Safety of AS01E-adjuvanted RSV Prefusion F Protein-based Candidate Vaccine (RSVPreF3 OA) When Co-administered With a Seasonal Quadrivalent Influenza Vaccine in Older Adults: Results of a Phase 3, Open-Label, Randomized Controlled Trial.

Co-administration of vaccines against respiratory syncytial virus (RSV) and influenza can be considered given their overlapping seasonality, and may increase vaccine uptake and compliance. In this phase 3, open-label, randomized study, we evaluated the immunogenicity, reactogenicity, and safety of the AS01E-adjuvanted RSV prefusion F protein-based candidate vaccine (RSVPreF3 OA) when co-administered with a seasonal quadrivalent influenza vaccine (FLU-QIV) in older adults. Participants aged ≥60 years (randomized 1:1) received either RSVPreF3 OA and FLU-QIV simultaneously on day 1 (Co-Ad group) or FLU-QIV on day 1 followed by RSVPreF3 OA on day 31 (sequential administration [SA] group). The co-primary objectives were to demonstrate noninferiority of RSVPreF3 OA in terms of RSV-A neutralization geometric mean titer (GMT) ratio and FLU-QIV in terms of hemagglutination inhibition GMT ratio for each FLU-QIV strain, when co-administered versus when administered alone at 1-month post-vaccination. Noninferiority was demonstrated if the upper limit of the 95% confidence interview of the group GMT ratio (SA/Co-Ad) was ≤1.5. Secondary descriptive objectives comprised additional immunogenicity assessments, reactogenicity, and safety. Of the 885 participants who received one dose of the study vaccines, 837 were included in the per protocol set. Demographic and baseline characteristics were balanced between the groups. Both co-primary objectives were met for both vaccines. Reported adverse events in both groups were mild-to-moderate, with a low frequency of grade 3 events. Data from this study demonstrate that RSVPreF3 OA can be co-administered with FLU-QIV. Co-administration is well tolerated, with an acceptable safety profile. NCT04841577.

The impact of social media interventions on adult influenza vaccination: A systematic review

This article was sponsored by CSL Seqirus. CSL Seqirus had no involvement in the writing or editorial process of this article. Background Despite recent interest around the impact of social media on COVID-19 vaccine uptake, there has not been a review of social media and adult ‘flu vaccinations. This review aims to look at whether social media interventions can improve ‘flu vaccine knowledge, intention to vaccinate and increase vaccine uptake. Methods We conducted a rapid systematic review of controlled intervention and observational studies that used existing social networks on commercial platforms, such as Facebook and Twitter. Findings Eight studies met our inclusion criteria. Due to heterogeneity in design, studies were thematically analyzed. Employment of influencers, multi-tasking, and the use of a verified source for information can impact positively on vaccine knowledge and intention to vaccinate. Interactions with postings tended to reinforce preconceived ideas. Conclusion Social media interventions can help to improve knowledge about ‘flu vaccine and intention to vaccinate but access to services remain a better determinant of vaccine uptake.

Assessing the relationship between existing childhood, adolescent and adult immunization programmes and national COVID-19 vaccination capacities in 2021

BackgroundDuring the COVID-19 pandemic, nearly all countries introduced COVID-19 vaccination programmes. Yet, countries had a wide range of programmatic experiences. This analysis aims to identify national characteristics associated with COVID-19 vaccination programmatic success. MethodsWe used the following outcome measures: the presence of national COVID-19 vaccination capacities and COVID-19 coverage as of December 2021, June 2022, and December 2022. We developed a standardized metric for assessing national COVID-19 vaccination capacities as a proxy for speed of introduction. We developed this metric through adaptation of the WHO Guide for Conducting an Expanded Programme on Immunization Review and consultations with technical experts specializing in vaccine introduction and emergency deployment; monitoring and data; childhood, adolescent and adult programmes; and COVID-19 vaccination roll-out. Through multivariable linear regressions, we evaluated whether having a mature immunization programme for children, adolescents and adults; recent use of emergency vaccination; World Bank income classification; past early adoption of new vaccines; density of the health workforce; and/or trust in science and government were associated with higher COVID-19 vaccination capacities and coverage. ResultsThe COVID-19 vaccination capacities scores ranged from 0 to 5 points with a global median score of 2 and an interquartile range of 1;4. After adjusting for World Bank income classifications, the presence of a mature influenza vaccination programme was independently correlated with statistically significant higher scores of national COVID-19 vaccination capacities and higher COVID-19 vaccination coverage in December 2021, June 2022, and December 2022. Trust in government was also associated with higher coverage for all three time stamps. ConclusionsAs countries consider how to prepare for and respond to future pandemics, having an adult seasonal influenza vaccination programme, building trust in government, and ensuring equitable access to vaccines supply emerged as key aspects that can benefit from additional national and global focus.

Does the South African government have a duty to fund influenza vaccination of adults 65 years and older?

In this paper, we draw on the thinking about solidarity, reciprocity and distributive justice grounded in Afro-communitarian ethics from the Global South to argue for institutions, particularly the South African (SA) government, have a prima facie duty to foster influenza vaccine uptake for adults 65 years and older. Although we focus specifically on the South African government to defend our position, we believe that our argument extends to all governments. Notably, these duties are that the SA government ought to make influenza vaccines freely available for the older adult in both the public and private health facilities, provided financial allocation and their extant relationships allow for this. Further, the SA government has a duty to improve influenza vaccine procurement and availability in the country, preferably through increasing manufacturing capabilities. This paper is intrinsically valuable to promote epistemic justice, thereby contributing toward the decolonization of the global healthcare system. Moreover, this project has social significance in contributing to mitigation efforts against future public health challenges associated with population aging in resource-limited developing African nations, wherein the impact of population transition will be felt most.

Concomitant Administration of Ad26.RSV.preF/RSV preF Protein Vaccine and High-dose Influenza Vaccine in Adults 65 Years and Older: a Noninferiority Trial.

Since influenza and respiratory syncytial virus (RSV) carry significant burden in older adults with overlapping seasonality, vaccines for both pathogens would ideally be coadministered in this population. Here we evaluate the immunogenicity and safety of concomitant administration of Ad26.RSV.preF/RSV preF protein and high-dose seasonal influenza vaccine (Fluzone-HD®) in adults ≥65 years old. Participants were randomized 1:1 to the Coadministration or Control group. The Coadministration group received concomitant Ad26.RSV.preF/RSV preF protein and Fluzone-HD® on Day 1 and placebo on Day 29, while the Control group received Fluzone-HD® and placebo at Day 1 and Ad26.RSV.preF/RSV preF protein on Day 29. Influenza hemagglutination-inhibiting and RSV preF-binding antibody titers were measured postvaccination and tested for noninferiority between both groups. Safety data were collected throughout the study and analyzed descriptively. Coadministered Ad26.RSV.preF/RSV preF protein and Fluzone-HD® vaccines induced noninferior immune responses compared to each vaccine administered alone. Seroconversion and seroprotection rates against influenza were similar between groups. Both vaccines remained well tolerated upon concomitant administration. Coadministration of Ad26.RSV.preF/RSV preF protein and Fluzone-HD® showed an acceptable safety profile and did not hamper the immunogenicity of either vaccine, thus supporting that both vaccines can be concomitantly administered in adults ≥65 years old.

A clinical and economic assessment of adjuvanted trivalent versus standard egg-derived quadrivalent influenza vaccines among older adults in the United States during the 2018-19 and 2019-20 influenza seasons

ABSTRACT Background Clinical evidence supports use of enhanced influenza vaccines in older adults. Few economic outcome studies have compared adjuvanted trivalent inactivated (aIIV3) and standard egg-derived quadrivalent inactivated influenza vaccines (IIV4e). Research Design and Methods A retrospective cohort study was conducted leveraging deidentified US hospital data linked to claims data during the 2018–19 and 2019–20 influenza seasons. Relative vaccine effectiveness (rVE) was compared in adults aged ≥ 65 years receiving aIIV3 or IIV4e using inverse probability of treatment weighting (IPTW) and Poisson regression. An economic assessment quantified potential real-world cost savings. Results The study included 715,807 aIIV3 and 320,991 IIV4e recipients in the 2018–19 and 844,169 aIIV3 and 306,270 IIV4e recipients in the 2019–20 influenza seasons. aIIV3 was significantly more effective than IIV4e in preventing cardiorespiratory disease (2018–19 rVE = 6.2%; and 2019–20 rVE = 6.0%) and respiratory disease (2018–19 rVE = 8.9%; and 2019–20 rVE = 10.1%). During the 2018–19 influenza season cardiorespiratory hospitalization cost savings for the aIIV3 population were $392 M, and $221 M for the 2019–20 season. Respiratory hospitalization cost savings for the aIIV3 population were $145 M and $97 M, respectively. Conclusions Our findings suggest that aIIV3 provides clinical and economic advantages versus IIV4e in the elderly.

Effect of influenza vaccination on resting metabolic rate and c-reactive protein concentrations in healthy young adults

Objectives Chronic immune activation and severe inflammatory states are positively associated with resting metabolic rate (RMR; kcal/day), but the impacts of mild immune stimuli on metabolism are poorly understood. This study investigates the within-individual association between the inflammatory response to influenza vaccination and RMR in young adults. Methods We evaluated RMRs through indirect calorimetry and circulating c-reactive protein (CRP) concentrations (mg/L)—a direct measure of inflammation—via high-sensitivity immunoassays of dried blood spots (n = 17) at baseline and two- and seven-days post-vaccine. Wilcoxon matched-pairs signed-rank tests were used to evaluate the magnitude of the CRP and RMR responses. Type II Wald chi-square tests of linear mixed-effect models assessed whether those responses were correlated. Results Baseline CRP was 1.39 ± 1.26 mg/L. On day two post-vaccine, CRP increased by 1.47 ± 1.37 mg/L (p &lt; 0.0001), representing a 106% increase above baseline values. CRP remained higher on day seven post-vaccine, 1.32 ± 2.47 mg/L (p = 0.05) above baseline values. There were no statistically significant changes in RMR from baseline to day two (p = 0.98) or day seven (p = 0.21). Change in CRP from baseline did not predict RMR variation across days (p = 0.46). Conclusions We find no evidence that adult influenza vaccination results in a corresponding increase in RMR. These results suggest that the energetic cost of an influenza vaccine’s mild inflammatory stimulus is either too small to detect or is largely compensated by a temporary downregulation of energy allocated to other metabolic tasks.

Ocular Adverse Events After Influenza Vaccination in Older Adults: Self-Controlled Case Series Using a Large Database in Japan

ABSTRACT Background To clarify the risk of adverse ocular events following influenza vaccination. Methods This self-controlled case series study used a claims database linked to vaccination records of a large city in Japan between April 2014 and September 2021. Individuals aged ≥ 65 years who developed adverse ocular events during the follow-up period were included. The exposure was influenza vaccination. The primary outcome was defined as the occurrence of at least one of the following five eye diseases: uveitis, scleritis, retinal vein occlusion, retinal artery occlusion, or optic neuritis. Conditional Poisson regression was used to estimate the within-subject incidence rate ratio of ocular adverse events during the risk period (0–56 days after vaccination) compared to the control period. Results A total of 4,527 cases were eligible for the study (median age, 74 years; male, 42%). The incidence rate ratio for the outcome during the risk period was 0.99 (95% confidence interval, 0.87 to 1.14). No increased risk was observed for individual components of the outcome either; the incidence rate ratio was 0.94 (0.78 to 1.13) for uveitis, 1.17 (0.86 to 1.59) for scleritis, 0.98 (0.76 to 1.27) for retinal vein occlusion, 0.89 (0.42 to 1.87) for retinal artery occlusion, and 0.87 (0.44 to 1.70) for optic neuritis. Conclusions This self-controlled case series showed no apparent increase in the risk of adverse ocular events after influenza vaccination among older adults. These results mitigate the concerns of older adults who may hesitate to receive influenza vaccination for fear of adverse ocular events. Abbreviation HR = hazard ratio; CI = confidence interval; RVO = retinal vein occlusion; SCCS = self-controlled case series

Supplemental Material for Optimizing Mood Prior to Influenza Vaccination in Older Adults: A Three-Arm Randomized Controlled Trial

Supplemental Material for Optimizing Mood Prior to Influenza Vaccination in Older Adults: A Three-Arm Randomized Controlled Trial