Influenza Vaccination in the Elderly

Effect of Current-Season-Only Versus Continuous Two-Season Influenza Vaccination on Mortality in Older Adults: A Propensity-Score-Matched Retrospective Cohort Study

BACKGROUND/OBJECTIVES

This study evaluated the impact of influenza vaccination on mortality using real-world data and compared the effect of current-season-only vaccination versus continuous two-season vaccination.

METHODS

The 2017-2019 data from the Center for Disease Control and Prevention of Shenzhen, Guangdong, China, included 880,119 individuals aged ≥65 years. The participants were divided into vaccinated and unvaccinated groups and matched using propensity scores with a 1:4 nearest-neighbor approach. Vaccinated individuals were further divided into current-season-only and continuous two-season vaccination groups, matched 1:1. Cox's multivariable proportional hazards regression models were used to assess the effect of vaccination on all-cause mortality, with Firth's penalized likelihood method applied to correct for a few events. The Fine-Gray competing risk models were used to assess the effect of vaccination on cardio-cerebral vascular disease (CCVD) mortality. Sensitivity analyses, including caliper matching, a nested case-control design, and Poisson's regression, were performed to test the robustness of the results.

RESULTS

Influenza vaccination reduced all-cause mortality by 39% (HR = 0.61, 95% CI: 0.47-0.80) and 55% (HR = 0.45, 95% CI: 0.33-0.60) in 2017-2018 and 2018-2019, respectively. Current-season-only vaccination showed stronger protective effects than continuous two-season vaccination (HR = 0.56, 95% CI: 0.31-0.99). Influenza vaccination reduced CCVD mortality by 46% (HR = 0.54, 95% CI: 0.34-0.84) in 2018-2019. The results were consistent across the sensitivity analyses.

CONCLUSIONS

Influenza vaccination was associated with a reduced risk of all-cause and CCVD mortality in older adults, underscoring the importance of routine influenza vaccination in older populations. Stronger effects were observed for current-season-only vaccination, warranting further research to confirm the association and explore mechanisms.

Influenza vaccine coverage and factors associated with non-vaccination among caregiving and care-receiving adults in the Canadian Longitudinal Study on Aging (CLSA)

BACKGROUND

Influenza vaccination is recommended for those at increased risk of influenza complications and their household contacts to help reduce influenza exposure. Adults who require care often experience health issues that could increase the risk of severe influenza and have close contact with caregivers. Assessing influenza vaccination prevalence in caregivers and care recipients can provide important information about uptake.

OBJECTIVES

We aimed to (1) estimate influenza non-vaccination prevalence and (2) assess factors associated with non-vaccination among caregivers aged ≥ 45 years and among care recipients aged ≥ 65 years.

METHODS

We conducted an analysis of cross-sectional data from the Canadian Longitudinal Study on Aging collected 2015-2018. We estimated non-vaccination prevalence and reported adjusted odds ratios with 95% confidence intervals from logistic regression models to identify factors associated with non-vaccination among caregivers and care recipients.

RESULTS

Of the 23,500 CLSA participants who reported providing care, 41.4% (95% CI: 40.8%, 42.0%) reported not receiving influenza vaccine in the previous 12 months. Among the 5,559 participants who reported receiving professional or non-professional care, 24.8% (95% CI: 23.7%, 26.0%) reported not receiving influenza vaccine during the same period. For both groups, the odds of non-vaccination were higher for those who had not visited a family doctor in the past year, were daily smokers, and those who identified as non-white.

DISCUSSION

Identifying groups at high risk of severe influenza and their close contacts can inform public health efforts to reduce the risk of influenza. Our results suggest sub-optimal influenza vaccination uptake among caregivers and care recipients. Efforts are needed to increase influenza vaccination and highlight the direct and indirect benefits for caregiver-care recipient pairs.

CONCLUSION

The proportions of both caregivers and care recipients who had not been vaccinated for influenza was high, despite the benefits of vaccination. Influenza vaccination campaigns could target undervaccinated, high-risk groups to increase coverage.

Cost-Effectiveness of the Use of Adjuvanted Quadrivalent Seasonal Influenza Vaccine in Older Adults in Ireland

BACKGROUND

Enhanced vaccines (e.g., containing adjuvants) have shown increased immunogenicity and effectiveness in older adults, who often respond sub-optimally to conventional influenza vaccines. In this study, we evaluated the cost-effectiveness of an inactivated, seasonal, MF59-adjuvanted quadrivalent influenza vaccine (aQIV) for use in adults ≥ 65 years in Ireland.

METHODS

A published dynamic influenza model incorporating social contact, population immunity, and epidemiological data was used to assess the cost-effectiveness of aQIV in adults ≥ 65 years of age compared with a non-adjuvanted QIV. Sensitivity analysis was performed for influenza incidence, relative vaccine effectiveness, excess mortality, and the impact on bed occupancy from co-circulating influenza and COVID-19.

RESULTS

The use of aQIV resulted in discounted incremental cost-effectiveness ratios (ICERs) of EUR 2420/quality-adjusted life years (QALYs) and EUR 12,970/QALY from societal and payer perspectives, respectively, both of which are below the cost-effectiveness threshold of EUR 45,000/QALY. Sensitivity analysis showed that aQIV was effective in most scenarios, except when relative vaccine effectiveness compared to QIV was below 3%, and resulted in a modest reduction in excess bed occupancy.

CONCLUSION

The use of aQIV for adults ≥ 65 years old in Ireland was shown to be highly cost-effective from both payer and societal perspectives.

Maintaining a 'fit' immune system: the role of vaccines

INTRODUCTION

Conventionally, vaccines are thought to induce a specific immune response directed against a target pathogen. Long recognized but poorly understood nonspecific benefits of vaccination, such as reduced susceptibility to unrelated diseases or cancer, are now being investigated and may be due in part to "trained immunity'.

AREAS COVERED

We discuss 'trained immunity' and whether vaccine-induced 'trained immunity' could be leveraged to prevent morbidity due to a broader range of causes.

EXPERT OPINION

The prevention of infection i.e. maintaining homeostasis by preventing the primary infection and resulting secondary illnesses, is the pivotal strategy used to direct vaccine design and may have long-term, positive impacts on health at all ages. In the future, we anticipate that vaccine design will change to not only prevent the target infection (or related infections) but to generate positive modifications to the immune response that could prevent a wider range of infections and potentially reduce the impact of immunological changes associated with aging. Despite changing demographics, adult vaccination has not always been prioritized. However, the SARS-CoV-2 pandemic has demonstrated that adult vaccination can flourish given the right circumstances, demonstrating that harnessing the potential benefits of life-course vaccination is achievable for all.

Influenza Vaccination for the Prevention of Cardiovascular Disease in the Americas: Consensus document of the Inter-American Society of Cardiology and the Word Heart Federation

Background

Cardiovascular mortality is decreasing but remains the leading cause of death world-wide. Respiratory infections such as influenza significantly contribute to morbidity and mortality in patients with cardiovascular disease. Despite of proven benefits, influenza vaccination is not fully implemented, especially in Latin America.

Objective

The aim was to develop a regional consensus with recommendations regarding influenza vaccination and cardiovascular disease.

Methods

A multidisciplinary team composed by experts in the management and prevention of cardiovascular disease from the Americas, convened by the Inter-American Society of Cardiology (IASC) and the World Heart Federation (WHF), participated in the process and the formulation of statements. The modified RAND/UCLA methodology was used. This document was supported by a grant from the WHF.

Results

An extensive literature search was divided into seven questions, and a total of 23 conclusions and 29 recommendations were achieved. There was no disagreement among experts in the conclusions or recommendations.

Conclusions

There is a strong correlation between influenza and cardiovascular events. Influenza vaccination is not only safe and a proven strategy to reduce cardiovascular events, but it is also cost saving. We found several barriers for its global implementation and potential strategies to overcome them.

Vaccination as a preventative measure contributing to immune fitness

The primary goal of vaccination is the prevention of pathogen-specific infection. The indirect consequences may include maintenance of homeostasis through prevention of infection-induced complications; trained immunity that re-programs innate cells to respond more efficiently to later, unrelated threats; slowing or reversing immune senescence by altering the epigenetic clock, and leveraging the pool of memory B and T cells to improve responses to new infections. Vaccines may exploit the plasticity of the immune system to drive longer-term immune responses that promote health at a broader level than just the prevention of single, specific infections. In this perspective, we discuss the concept of “immune fitness” and how to potentially build a resilient immune system that could contribute to better health. We argue that vaccines may contribute positively to immune fitness in ways that are only beginning to be understood, and that life-course vaccination is a fundamental tool for achieving healthy aging.

Effects of influenza vaccination on clinical outcomes of chronic obstructive pulmonary disease: A systematic review and meta-analysis

PURPOSE

Influenza is a threat to patients with chronic obstructive pulmonary disease (COPD), influenza vaccination help to reduce incidence of influenza infection, however, whether it is beneficial to COPD patients in clinical outcomes lacks for evidence due to limited studies and participations.

METHODS

We searched PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure (CNKI) and China Science and Technology Journal Database (CSTJ) to retrieve eligible studies regardless of study design published before August 2020, and conducted meta-analysis with odds ratio (OR) and mean difference (MD). The quality of included studies and pooled evidences were assessed. Narrative summaries were provided where data were insufficient for meta-analysis.

RESULTS

2831 COPD patients were included, the pooled results showed that influenza vaccination reduced the exacerbations (P = 0.0001) and trends of hospitalizations (P = 0.09) in COPD patients. Further subgroup analysis showed that the reduction of exacerbations and hospitalizations were significant in patients with FEV₁<50 % predicted (P = 0.01 and P < 0.0001 respectively), but not in those with FEV₁≥50 % predicted (P = 0.23 and P = 0.76 respectively). No significant effect of influenza vaccination on all-cause mortality was observed.

CONCLUSIONS

Our findings support a protective role of influenza vaccination in COPD patients, a yearly influenza vaccination should be strongly recommended for all COPD patients, especially those with severe airflow limitation, to reduce possible influenza infection, and thus associated exacerbations and hospitalizations.

Knowledge, attitudes, and practices of seasonal influenza vaccination among older adults in nursing homes and daycare centers, Honduras

Background

Older adults represent 70–90% of seasonal influenza-related deaths and 50–70% of influenza-related hospitalizations. Vaccination is the most efficient means of preventing influenza and reducing influenza-related illnesses. We aimed to describe knowledge, attitudes, and practices (KAP) of seasonal influenza vaccination among older adults in Honduras.

Methods

From August 29–October 26, 2018, we conducted a cross-sectional KAP survey regarding seasonal influenza vaccinations to samples of older adults 1) admitted to nursing homes and 2) attending daycare centers. We used the Minimental State Examination (MMSE) psychometric tool to assess the cognitive status of older adults and included participants with scores of ≥23 points in the survey. We reported frequency distributions for demographics, KAP of influenza virus and vaccination, and vaccination coverage. We used logistic regression to analyze associations between demographics and verified influenza vaccination.

Results

Of 511 MMSE participants, 341 completed the survey (95 adults in 12 nursing homes and 246 older adults in ten daycare centers). Almost all participants knew that influenza causes severe illness and may be transmitted from person to person, vaccination is safe and protects against disease, and older adults have greater risk of complications. Of 284 participants with verified vaccinations, 81.3% were vaccinated for influenza: 87.9% attending daycare centers and 61.4% in nursing homes. Among all participants, verified current influenza vaccination was associated with self-reported influenza vaccination in previous year (aOR: 14.05; 95% CI: 5.36–36.81); no formal education (aOR: 4.83; 95% CI: 1.63–14.37) or primary school education (aOR: 4.51; 95% CI: 1.79–11.37) having ≥secondary as reference; and indigenous (aOR: 4.55; 95% CI: 1.18–17.49) having Mestizo as reference. Reasons for vaccination were perceived self-benefits, protection against influenza complications, favorable vaccination hours, and healthcare provider recommendations.

Conclusion

Four-fifths of older adults were vaccinated for seasonal influenza. Educational efforts provided in conjunction with vaccination campaigns resulted in high knowledge of influenza virus, transmission, and vaccination. Further outreach regarding disease risks and vaccine safety needs to be directed towards older adults in nursing homes who had lower knowledge and coverage than older adults in daycare centers.

Influenza and Pneumococcal Vaccination in Non-Infected Cardiometabolic Patients from the Americas during the COVID-19 Pandemic. A Sub-Analysis of the CorCOVID-LATAM Study

BACKGROUND

Influenza vaccination (IV) and Pneumococcus vaccination (PV) are recommended for patients with cardiometabolic diseases. This study aimed to evaluate the immunization rate of ambulatory cardiometabolic patients during the COVID-19 pandemic in the Americas.

METHODS

Electronic surveys were collected from 13 Spanish speaking countries between 15 June and 15 July 2020.

RESULTS

4216 patients were analyzed. Mean age 60 (±15) years and 49% females. Global IV rate was 46.5% and PV 24.6%. Vaccinated patients were older (IV = 63 vs. 58 years; PV = 68 vs. 59, p < 0.01) but without gender difference. Vaccination rates were greater in higher-risk groups (65+, diabetics, heart failure), but not in coronary artery disease patients. In the Southern cone, the rate of IV and PV was approximately double that in the tropical regions of the Americas. In a multivariate model, geographic zone (IV = OR 2.02, PV = OR 2.42, p < 0.001), age (IV = OR 1.023, PV = OR 1.035, p < 0.001), and incomes (IV = OR 1.28, PV = OR 1.58, p < 0.001) were predictors for vaccination.

CONCLUSIONS

During the COVID-19 pandemic, ambulatory patients with cardiometabolic diseases from the Americas with no evidence of COVID-19 infection had lower-than-expected rates of IV and PV. Geographic, social, and cultural differences were found, and they should be explored in depth.

Relative effectiveness of high dose versus standard dose influenza vaccines in older adult outpatients over four seasons, 2015-16 to 2018-19

BACKGROUND

New influenza vaccine formulations are designed to improve vaccine effectiveness and protect those most vulnerable to infection. High dose trivalent inactivated influenza vaccine (HD-IIV3), licensed for ages ≥65 years, produces greater antibody responses and efficacy in clinical trials, but post-licensure vaccine effectiveness (VE) compared to standard dose (SD-IIV3/4) vaccine remains an open question.

METHODS

Using a test-negative, case control design and propensity analyses to adjust for confounding, US Influenza VE Network data from the 2015-2016 through 2018-2019 seasons were analyzed to determine relative VE (rVE) between HD-IIV3 and SD-IIV3/4 among outpatients ≥65 years old presenting with acute respiratory illness. Influenza vaccination status was derived from electronic medical records and immunization registries.

RESULTS

Among 3861 enrollees, 2993 (78%) were vaccinated; 1573 (53%) received HD-IIV3 and 1420 (47%) received SD-IIV3/4. HD-IIV3 recipients differed from SD-IIV3/4 recipients by race, previous vaccination, number of outpatient visits in the previous year and timing of vaccination, and were balanced in the propensity model except the timing of vaccination. Compared with no vaccination, significant protection against any influenza A was observed from both HD-IIV3 (VE = 29%; 95%CI = 10%, 44%) and SD-IIV3/4 (VE = 24%; 95%CI = 5%, 39%); rVE = 18% (95%CI = 0%, 33%, SD as referent). When stratified by virus type, against A/H1N1, HD-IIV3 VE was 30% (95%CI = -7%, 54%), SD-IIV3/4 VE was 40% (95%CI = 10%, 61%), and rVE = -32%; (95%CI = -94%, 11%); Against A/H3N2, HD-IIV3 VE was 31% (95%CI = 9%, 47%), SD-IIV3/4 VE was 19% (95%CI = -5%, 37%), and rVE = 27%; (95% CI = 9%, 42%).

CONCLUSIONS

Among adults ≥65 years of age, recipients of standard and high dose influenza vaccines differed significantly in their characteristics. After adjusting for these differences, high dose vaccine offered more protection against A/H3N2 and borderline significant protection against all influenza A requiring outpatient care during the 2015-2018 influenza seasons.

Expanding the role of bacterial vaccines into life-course vaccination strategies and prevention of antimicrobial-resistant infections

A crisis in bacterial infections looms as ageing populations, increasing rates of bacteraemia and healthcare-associated infections converge with increasing antimicrobial resistance and a paucity of new antimicrobial classes. New initiatives are needed to develop bacterial vaccines for older adults in whom immune senescence plays a critical role. Novel vaccines require an expanded repertoire to prevent mucosal diseases such as pneumonia, skin and soft tissue infections and urinary tract infections that are major causes of morbidity and mortality in the elderly, and key drivers of antimicrobial resistance. This review considers the challenges inherent to the prevention of bacterial diseases, particularly mucosal infections caused by major priority bacterial pathogens against which current vaccines are sub-optimal. It has become clear that prevention of many lung, urinary tract and skin infections requires more than circulating antibodies. Induction of Th1/Th17 cellular responses with tissue-resident memory (Trm) cells homing to mucosal tissues may be a pre-requisite for success.

Benefits of Exercise on Influenza or Pneumonia in Older Adults: A Systematic Review

A coronavirus pandemic has recently become one of the greatest threats the world is facing. Older adults are under a high risk of infection because of weaker immune systems. Therefore, the purpose of this review is to summarize the recent scientific evidence that outlines the effects of exercise on influenza or pneumonia in older adults. An electronic literature search was conducted using the WEB OF SCIENCE, SCIENCEDIRECT and GOOGLE SCHOLAR databases using the following keywords, "Exercise," "Older adult," "Influenza," and "Pneumonia." Any randomized control trials, cross-sectional and observational studies that related to this topic were all included. Twenty studies met the eligibility criteria for this review. Thirteen randomized control trials investigated the effects of exercise on the immune responses to influenza or pneumonia vaccination: seven trials employed moderate aerobic exercise, three employed resistance exercise, and the remaining three used Asian martial arts or special home-based exercises. Five cross-sectional and two observational studies examined the associations between exercise/physical condition and influenza/pneumonia. Most of the current studies suggested that prolonged moderate aerobic exercise may help to reduce the risk of influenza-related infection and improve the immune responses to influenza or pneumonia vaccination in older adults. In addition, training in traditional Asian martial arts was also found to be beneficial. Future research should focus on the different effects of moderate and vigorous exercise on influenza-related diseases.

The effects of health literacy in influenza vaccination competencies among community-dwelling older adults in Hong Kong

BACKGROUND

Poor health literacy was found to be one of the key barriers in older adults' disease prevention practice. However, it has still been unclear how different processes in health literacy play a role in older adult's vaccination-related competencies. By adopting the European Health Literacy Survey (HLS-EU), the current study aimed to examine older adults' competences in accessing, understanding, evaluating and applying health information, as well as how they are related to perceived difficulties in vaccination-related practices. .

METHODS

With a cross-sectional design, a quantitative exploratory study was conducted using structured questionnaires. Four-hundred and 86 community-dwelling older adults aged 65 and above were recruited from non-government organizations in Hong Kong. Health literacy was measured by the Chinese version of 47-item HLS-EU (HLS-Asia-Q), which assesses the competences in accessing, understanding, evaluating and applying health information across the domains of health care, disease prevention, and health promotion. Linear regression was performed to test the association between different aspects of health literacy and vaccination-related information processing.

RESULTS

The findings showed that the health literacy of Hong Kong older adults has been limited, particularly in information appraisal. Poorer competences in accessing and appraising health information were associated with greater difficulties in making vaccination decision.

CONCLUSIONS

By identifying the health literacy processes associated with vaccination, our findings suggested that health-promotion programs strengthening the appraisal and comparison of vaccination information should be provided for the general public. Meanwhile, health professionals and mass media should reduce the complexity when delivering the health messages, and make it easier for older adults to access and comprehend, thus increasing the inclination to take vaccine and preventing the spread of communicable diseases.

Opportunities to improve influenza vaccination rates in general medical inpatients

Influenza vaccination is an important preventative health measure. A significant proportion of general medical inpatients meets indications for annual inactivated influenza vaccination (IIV), as recommended by the Australian National Immunisation Programme. This study explores opportunities to provide IIV to eligible general medical inpatients and associated barriers.

On field vaccine effectiveness in three periods of 2018/2019 influenza season in Emilia-Romagna Region

Background and aim of the work: Epidemic influenza is associated with significant morbidity and mortality, particularly in people at risk. The vaccine reduces complications, hospitalization and mortality excess, as well as health care and social costs. Aim of the study was to estimate the influenza vaccine effectiveness (VE) in Emilia-Romagna Region during the 2018/2019 season. Methods: Within the context of virological surveillance conducted at the Regional Reference Laboratory of Parma, nasal/throat swabs were performed by sentinel practitioners and clinicians, on patients with ILI (Influenza-like illness). VE estimates, overall and against subtype A(H1N1)pdm09 and A(H3N2), were evaluated in three periods of the season, using a test-negative case-control design. Results: From November 2018 to April 2019, 2,230 specimens were analyzed: 1,674 (75.1%) performed by clinicians and 556 (24.9%) by sentinel practitioners of the regional network. The season was characterized by the predominant circulation of influenza type A viruses: 57.4% belonged to subtype A(H3N2), 41.2% to subtype A(H1N1)pdm09. 23.5% of patients was vaccinated against influenza with quadrivalent or adjuvate vaccine. The overall VE was -5% (95% CI -33% - 18%) with a decreasing trend during the season. The overall VE against subtype A(H1N1)pdm09 was 39% (95% CI 11% - 58%) and remained stable during the season. The overall VE against subtype A(H3N2) was -43% (95% CI -89% - -9%), and showed an important decreasing trend. Conclusions: The possibility to make accurate and continuous VE estimates during the season will help to better define the composition of the vaccine for the following season. (www.actabiomedica.it)

EXamining the knowledge, Attitudes and experiences of Canadian seniors Towards influenza (the EXACT survey)

Background

Older adults are at high risk for influenza-related complications including worsening frailty and function. We surveyed older Canadians to explore the impact of influenza and determine how influenza knowledge influences vaccination decision-making.

Methods

We disseminated an online survey through a national polling panel. The survey included questions about the respondents’ influenza vaccination practices and knowledge about influenza. Using validated measures, they reported their frailty and functional status prior to the 2016/17 influenza season, during illness (if applicable), and following the season. Regression analyses were used to examine predictors of poor functional outcomes.

Results

Five thousand and fourteen adults aged 65 and older completed the survey; mean age was 71.3 ± 5.17 years, 42.6% had one or more chronic conditions, 7.8% were vulnerable and 1.8% were frail. 67.9% reported receiving last season’s influenza vaccine. Those who rarely/never receive the influenza vaccine were significantly less likely to correctly answer questions about influenza’s impact than those who receive the vaccine more consistently. Of the 1035 (21.5%) who reported experiencing influenza or influenza-like illness last season, 40% indicated a recovery longer than 2 weeks, and one-fifth had health and function declines during this time. Additionally, 3.1% of those afflicted “never fully recovered”. Older age, significant trouble with memory and having influenza/ILI were among the independent predictors of persistent declines in health and function.

Conclusions

Given that frailty and function are important considerations for older adults’ well-being and independence, healthcare decision-makers must understand the potential for significant temporary and long-term impacts of influenza to make informed vaccine-related policies and recommendations.

Excess Deaths Attributable to Influenza-Like Illness in the ESRD Population

BACKGROUND

Morbidity and mortality vary seasonally. Timing and severity of influenza seasons contribute to those patterns, especially among vulnerable populations such as patients with ESRD. However, the extent to which influenza-like illness (ILI), a syndrome comprising a range of potentially serious respiratory tract infections, contributes to mortality in patients with ESRD has not been quantified.

METHODS

We used data from the Centers for Disease Control and Prevention (CDC) Outpatient Influenza-like Illness Surveillance Network and Centers for Medicare and Medicaid Services ESRD death data from 2000 to 2013. After addressing the increasing trend in deaths due to the growing prevalent ESRD population, we calculated quarterly relative mortality compared with average third-quarter (summer) death counts. We used linear regression models to assess the relationship between ILI data and mortality, separately for quarters 4 and 1 for each influenza season, and model parameter estimates to predict seasonal mortality counts and calculate excess ILI-associated deaths.

RESULTS

An estimated 1% absolute increase in quarterly ILI was associated with a 1.5% increase in relative mortality for quarter 4 and a 2.0% increase for quarter 1. The average number of annual deaths potentially attributable to ILI was substantial, about 1100 deaths per year.

CONCLUSIONS

We found an association between community ILI activity and seasonal variation in all-cause mortality in patients with ESRD, with ILI likely contributing to >1000 deaths annually. Surveillance efforts, such as timely reporting to the CDC of ILI activity within dialysis units during influenza season, may help focus attention on high-risk periods for this vulnerable population.

Influenza Vaccination in Older Adults: Recent Innovations and Practical Applications

Influenza can lead to serious illness, particularly for older adults. In addition to short-term morbidity and mortality during the acute infection, recovery can be prolonged and often incomplete. This may lead to persistent declines in health and function, including catastrophic disability, which has dramatic implications for the well-being and support needs of older adults and their caregivers. All of this means that prevention of infection and effective treatment when illness has occurred are of paramount importance. In this narrative review, we discuss the effectiveness of influenza vaccines for the prevention of influenza illness and serious outcomes in older adults. We review evidence of vaccine effectiveness for older adults in comparison with younger age groups, and also highlight the importance of frailty as a determinant of vaccine effectiveness. We then turn our attention to the question of why older and frailer individuals have poorer vaccine responses, and consider changes in immune function and inflammatory responses. This sets the stage for a discussion of newer influenza vaccine products that have been developed with the aim of enhancing vaccine effectiveness in older adults. We review the available evidence on vaccine efficacy, effectiveness and cost benefits, consider the potential place of these innovations in clinical geriatric practice, and discuss international advisory committee recommendations on influenza vaccination in older adults. Finally, we highlight the importance of influenza prevention to support healthy aging, along with the need to improve vaccine coverage rates using available vaccine products, and to spur development of better influenza vaccines for older adults in the near future.

Canadian older adults' perceptions of effectiveness and value of regular and high-dose influenza vaccines

Influenza vaccination is an important public health intervention for older adults, yet vaccination rates remain suboptimal. We conducted an online survey of Canadians ≥ 65 years to explore satisfaction with publicly-funded standard-dose influenza vaccines, and perceptions of the need for a more effective product. They were provided with information about currently approved influenza vaccines, and were asked about their preferences should all formulations be available for free, and should the recently approved high-dose (HD) vaccine for seniors be available at a cost. From March to April 2017, 5014 seniors completed the survey; mean age was 71.3 ± 5.17 years, 50% were female, and 42.6% had one or more chronic conditions. 3403 (67.9%) had been vaccinated against influenza in the 2016/17 season. Of all respondents, 3460 (69%) were satisfied with the standard-dose influenza vaccines, yet 3067 (61.1%) thought that a more effective vaccine was/may be needed. If HD was only available at a cost, 1426 (28.4%) respondents would consider it, of whom 62.9% would pay $20 or less. If all vaccines were free next season, 1914 (38.2%) would opt for HD (including 12.2% of those who previously rejected influenza vaccines), 856 (17.1%) would choose adjuvanted vaccine, and 558 (11.1%) standard-dose vaccine. 843 (16.8%) of respondents were against vaccines, 451 (9.0%) had no preference and 392 (7.8%) were uncertain. Making this product available through publicly funded programs may be a strategy to increase immunization rates in this population.

Influenza vaccination in the elderly: Is a trial on mortality ethically acceptable?

The effectiveness of influenza vaccination in the elderly has long been a topic of debate, fueled by the absence of direct evidence from randomized trials on its effect on mortality and the methodological limitations of observational studies pointing this direction. It is argued that new placebo-controlled trials should be undertaken to resolve this uncertainty. However, such trials may be ethically questionable. To bring this discussion forward, we provide a comprehensive overview of the ethical challenges of an influenza vaccine efficacy trial designed to evaluate mortality in the elderly. An important condition in the justification of a trial is the existence of genuine uncertainty in regard to the answer to a research question. Therefore an extensive analysis of the existing levels of knowledge is needed to support the conclusion that an effect of vaccination on mortality is uncertain. Even if a so called "clinical equipoise" status applies, denying a control group vaccination would be problematic because vaccination is considered "competent care" and withholding vaccination could substantially increase patients' risk for influenza and its complications. Given the high burden of disease and already proven benefits of vaccination, such a trial is unlikely to meet the Declaration of Helsinki stating that the importance of a trial must outweigh the risk patients are exposed to. While a placebo-controlled trial in vaccine refusers may be considered, such a trial is unlikely to meet substantial methodological barriers regarding trial size and generalizability. We conclude that a new trial is unlikely to provide for a direct answer, let alone change current policy. At the same time, given the lack of consensus on the ethical acceptability of a placebo-controlled trial on the effect of influenza vaccination on mortality in the elderly, we invite researchers considering such trials to address the ethical challenges discussed in this manuscript.

Human T cell immunosenescence and inflammation in aging

The aging process is driven by a finite number of inter-related mechanisms that ultimately lead to the emergence of characteristic phenotypes, including increased susceptibility to multiple chronic diseases, disability, and death. New assays and analytical tools have become available that start to unravel some of these mechanisms. A prevailing view is that aging leads to an imbalance between stressors and stress-buffering mechanisms that causes loss of compensatory reserve and accumulation of unrepaired damage. Central to this paradigm are changes in the immune system and the chronic low-grade proinflammatory state that affect many older individuals, even when they are apparently healthy and free of risk factors. Independent of chronological age, high circulating levels of proinflammatory markers are associated with a high risk of multiple adverse health outcomes in older persons. In this review, we discuss current theories about causes and consequences of the proinflammatory state of aging, with a focus on changes in T cell function. We examine the role of NF-κB activation and its dysregulation and how NF-κB activity differs among subgroups of T cells. We explore emerging hypotheses about immunosenescence and changes in T cell behavior with age, including consideration of the T cell antigen receptor and regulatory T cells (T_regs). We conclude by illustrating how research using advanced technology is uncovering clues at the core of inflammation and aging. Some of the preliminary work in this field is already improving our understanding of the complex mechanisms by which immunosenescence of T cells is intertwined during human aging.

The association between red cell distribution width and poor outcomes in hospitalized patients with influenza

PURPOSE

To examine an association between red blood cell distribution width (RDW) and the prognosis of influenza patients.

METHODS

We conducted a retrospective analysis of patients hospitalized with influenza during 2012-2015 in the internal medicine wards of one medical center. RDW measurements during hospitalization were analyzed. Primary outcome was complicated hospitalization (defined as at least one of: length of stay ≥7days, need for mechanical ventilation, septic shock, transfer to intensive-care, or 30-day mortality). Secondary outcome was 30-day mortality.

RESULTS

153 patients were included, mean age: 62.5±1, 82 (54%) male; 84 (55%) had a high RDW value (>14.5%) during hospitalization. Patients with high and low RDW (≤14.5%) had similar age and comorbidity profiles, but those with high RDW had lower hemoglobin and higher creatinine levels. Patients with high RDW had a higher rate of complicated hospitalization (32.5% vs. 10.3%, p<0.01) and a trend for increased 30-day mortality. In a multivariate regression model, high RDW was a predictor of complicated hospitalization (OR 5.03, 95% CI 1.81-13.93, p<0.01). Each 1-point increase in RDW was associated with a 29% increase in the risk for the primary outcome.

CONCLUSION

RDW>14.5% was a predictor of severe hospital complications in patients with influenza.

Beliefs and attitudes towards the influenza vaccine in high-risk individuals

Societal and economic impact of influenza is mainly due to influenza infection of specific groups, who are at higher risk of health complications leading up to hospitalisation or death. In this study we applied the health belief model (HBM) to evaluate beliefs and attitudes towards influenza disease and vaccine in community-dwelling high-risk individuals (aged 65 or more or having a chronic disease). We conducted a mixed-method study using data collected through a telephone survey of a household unit sample. We used thematic analysis to map responses to HBM dimensions and Poisson regression to model vaccine non-uptake prevalence. The main self-reported reason not to take the vaccine referred to the susceptibility dimension: 'considering oneself to be a healthy person' (29·8%, (95% confidence interval (CI) 22·1-38·7)). Bad experiences after vaccination - barriers dimension - were also commonly reported (17·0%, (95% CI 10·8-23·8)). Vaccine non-uptake prevalence was 22% higher in those who did not consider themselves susceptible to contract flu (Prevalence Ratio (PR) = 1·22, (95% CI 1·0-1·5)) and 18% lower in those who did not consider that the vaccine causes flu symptoms (PR = 0·82, (95% CI 0·68-0·99)). Results suggest that high-risk individuals do not think of themselves susceptible to influenza infection and fear adverse events following immunisation.

Immunogenicity and safety of a quadrivalent inactivated influenza vaccine compared with two trivalent inactivated influenza vaccines containing alternate B strains in adults: A phase 3, randomized noninferiority study

BACKGROUND

Vaccination is the most effective means of influenza prevention. Efficacy of trivalent vaccines may be enhanced by including both B strain lineages. This phase 3, double-blind study assessed the immunogenicity and safety/tolerability of a quadrivalent inactivated influenza vaccine (IIV4) versus the United States (US)-licensed 2014-2015 trivalent inactivated influenza vaccine (IIV3-Yamagata [IIV3-YAM]; Afluria) and IIV3 containing the alternate Victoria B strain (IIV3-VIC) in adults ≥18years.

METHODS

Participants (n=3484) were randomized 2:1:1 and stratified by age to receive IIV4 (n=1741), IIV3-YAM (n=871), or IIV3-VIC (n=872). The primary objective was to demonstrate noninferiority of the immunological response to IIV4 versus IIV3-YAM and IIV3-VIC. Noninferiority was assessed by hemagglutination inhibition geometric mean titer (GMT) ratio (IIV3/IIV4; upper bound of two-sided 95% confidence interval [CI]≤1.5) and seroconversion rate (SCR) difference (IIV3 - IIV4; upper bound of two-sided 95% CI≤10%) for vaccine strains. Solicited local and systemic adverse events (AEs) were assessed for 7days postvaccination, AEs recorded for 28days postvaccination, and serious AEs for 6months postvaccination.

RESULTS

IIV4 elicited a noninferior immune response for matched strains, and superior response for unmatched B strains not contained in IIV3 comparators. Adjusted GMT ratios (95% CI) for A/H1N1, A/H3N2, B/YAM, and B/VIC strains were 0.93 (0.88, 0.99), 0.93 (0.88, 0.98), 0.87 (IIV3-YAM; 0.82, 0.93), and 0.95 (IIV3-VIC; 0.88, 1.03), respectively. Corresponding values for SCR differences (95% CI) were -1.1 (-4.5, 2.3), -1.7 (-5.0, 1.7), -3.2 (IIV3-YAM; -7.4, 0.9), and -1.6 (IIV3-VIC; -5.8, 2.5). AEs were generally mild and experienced by 52.9% of participants. Serious AEs were reported with a slightly higher frequency with IIV4 (2.3%) versus IIV3-YAM (1.6%) and IIV3-VIC (1.5%).

CONCLUSIONS

IIV4 demonstrated immunological noninferiority to the US-licensed IIV3, and superiority for unmatched B strains not contained in IIV3 comparators. Safety/tolerability profiles were similar across vaccine groups.

FUNDING

Seqirus; Clinicaltrials.gov: NCT02214225.

Racial and Ethnic Disparities in Influenza Vaccination among Adults with Chronic Medical Conditions Vary by Age in the United States

BACKGROUND

People living with chronic health conditions exhibit higher risk for developing severe complications from influenza according to the Centers for Diseases Control and Prevention. Although racial and ethnic disparities in influenza vaccination have been documented, it has not been comprehensively determined whether similar disparities are present among the adult population with at least one such condition.

OBJECTIVE

To study if racial and ethnic disparities in relation to influenza vaccination are present in adults suffering from at least one chronic condition and if such inequalities differ between age groups.

METHODS

The Medical Expenditure Panel Survey (2011-2012) was used to study the adult population (age ≥18) who had at least one chronic health condition. Baseline differences in population traits across racial and ethnic groups were identified using a chi-square test. This was conducted among various age groups. In addition, survey logistic regression was utilized to produce odds ratios of receiving influenza vaccination annually between racial and ethnic groups.

RESULTS

The total sample consisted of 15,499 adults living with at least one chronic health condition. The numbers of non-Hispanic whites (whites), non-Hispanic blacks (blacks), and Hispanics were 8,658, 3,585, and 3,256, respectively. Whites (59.93%) were found to have a higher likelihood of self-reporting their receipt of the influenza vaccine in comparison to the black (48.54%) and Hispanic (48.65%) groups (P<0.001). When examining persons aged 50-64 years and ≥65 years, it was noted that the black (54.99%, 62.72%) and Hispanic (53.54%, 64.48%) population had lower rates of influenza vaccine coverage than the white population (59.22%, 77.89) (both P<0.0001). No significant differences between whites and the blacks or Hispanics were found among the groups among adults between 18 and 49 inclusive (P>0.05). After controlling for patient characteristics, the difference in influenza vaccine coverage between whites and the minority groups were no longer significant for adults aged 50-64 years. However, the difference were still statistically significant for those aged ≥65 years.

CONCLUSIONS

In the United States, there are significant disparities in influenza vaccination by race and ethnicity for adults over 65 years with at least one chronic health condition. Future research is needed to help develop more targeted interventions to address these issues and improve influenza vaccination rates.

Viral RNA in the influenza vaccine may have contributed to the development of ANCA-associated vasculitis in a patient following immunisation

A number of large studies have demonstrated influenza vaccinations to be safe and effective. However, there have been some sporadic case reports, describing a temporal association of influenza vaccination with onset or relapse of anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis. The nature of this association, beyond time of occurrence, remains unknown. The presentation of a previously healthy patient who developed ANCA-associated vasculitis (AAV) shortly after influenza vaccination provided us with the rare opportunity to study the possible mechanisms behind this observation. We tested the ability of different types and batches of influenza vaccines to stimulate proteinase-3 ANCA (PR3-ANCA) production in vitro. We found that only some influenza vaccines stimulated PR3-ANCA production in this patient. We demonstrated that this unusual response was associated with those vaccines that contained viral ribonucleic acid (RNA), the natural ligand for Toll-like receptor-7. Exome sequencing of the patient's DNA did not show any mutation in any of the molecules associated with Toll-like receptor signalling. We propose that hyper-reaction to viral RNA in the influenza vaccine may have contributed to the development of AAV following influenza vaccination in this patient.

Age-associated changes in basal NF-κB function in human CD4+ T lymphocytes via dysregulation of PI3 kinase

Immune impairment and high circulating level of pro-inflammatory cytokines are landmarks of human aging. However, the molecular basis of immune dys-regulation and the source of inflammatory markers remain unclear. Here we demonstrate that in the absence of overt cell stimulation gene expression mediated by the transcription factor NF-κB is higher in purified and rested human CD4⁺ T lymphocytes from older compared to younger individuals. This increase of NF-κB-associated transcription includes transcripts for pro-inflammatory cytokines such as IL-1 and chemokines such as CCL2 and CXCL10. We demonstrate that NF-κB up-regulation is cell-intrinsic and mediated in part by phosphatidylinositol 3-kinase (PI3K) activity induced in response to metabolic activity, which can be moderated by rapamycin treatment. Our observations provide direct evidence that dys-regulated basal NF-κB activity may contribute to the mild pro-inflammatory state of aging.

Accuracy of influenza vaccination rate estimates in United States nursing home residents

The US Center for Medicare and Medicaid Services (CMS) requires nursing homes and long-term-care facilities to document residents' vaccination status on the Resident Assessment Instrument (RAI). Vaccinating residents can prevent costly hospital admissions and deaths. CMS and public health officials use RAI data to measure vaccination rates in long-term-care residents and assess the quality of care in nursing homes. We assessed the accuracy of RAI data against medical records in 39 nursing homes in Florida, Georgia, and Wisconsin. We randomly sampled residents in each home during the 2010-2011 and 2011-2012 influenza seasons. We collected data on receipt of influenza vaccination from charts and RAI data. Our final sample included 840 medical charts with matched RAI records. The agreement rate was 0·86. Using the chart as a gold standard, the sensitivity of the RAI with respect to influenza vaccination was 85% and the specificity was 77%. Agreement rates varied within facilities from 55% to 100%. Monitoring vaccination rates in the population is important for gauging the impact of programmes and policies to promote adherence to vaccination recommendations. Use of data from RAIs is a reasonable approach for gauging influenza vaccination rates in nursing-home residents.

Barriers and Motivators of Influenza Vaccination Uptake among Primary Healthcare Workers in Singapore

Introduction:

Healthcare workers, especially primary healthcare workers, are at risk of contracting influenza from patients at their workplace. The uptake of influenza immunisation among healthcare workers has been inadequate in spite of this risk and the recommendation to receive annual influenza vaccination. This study aims to assess the barriers as well as the motivators of influenza immunisation among staff from an organisation of primary healthcare polyclinics in Singapore.

Methods:

Focus group interviews were conducted on healthcare workers from different occupation categories within the organisation and results were analysed.

Results:

Factors identified as barriers to influenza immunisation were: misconceptions regarding influenza immunisation, fear of experiencing pain or reaction from the vaccination, influence from other staff, uncertainty over the efficacy of influenza vaccination and perceived immunity against influenza virus. Motivators to immunisation were: the influence of other staff, direction from senior management, incentives for vaccination, accessibility and convenience in receiving the immunisation, reduction in risk of transmitting influenza to others and awareness and knowledge of influenza vaccination.

Conclusion:

Interventions to promote influenza immunisation based on these identified factors may help increase the immunisation uptake among healthcare workers.

Trends in influenza vaccination coverage in Portugal from 1998 to 2010: effect of major pandemic threats

Background

Vaccination is the key measure available for prevention of the public health burden of annual influenza epidemics. This article describes national trends in seasonal influenza vaccine (IV) coverage in Portugal from 1998/99 to 2010/11, analyzes progress towards meeting WHO 2010 coverage goals, and addresses the effect of major public health threats of the last 12 years (SARS in 2003/04, influenza A (H5N1) in 2005/06, and the influenza A (H1N1)2009 pandemic) on vaccination trends.

Methods

The National Institute of Health surveyed (12 times) a random sample of Portuguese families. IV coverage was estimated and was adjusted for age distribution and country region. Independence of age and sex coverage distribution was tested using a modified F-statistic with a 5% significance level. The effect of SARS, A (H5N1), and the A (H1N1)2009 pandemic was tested using a meta-regression model. The model was adjusted for IV coverage in the general population and in the age groups.

Results

Between 1998/99 and 2010/11 IV, coverage in the general population varied between 14.2% (CI _95%: 11.6%–16.8%) and 17.5% (CI _95%: 17.6%–21.6%). There was no trend in coverage (p = 0.097). In the younger age group (<15 years) a declining trend was identified until 2008/09 (p = 0.005). This trend reversed in 2009/10. There was also a gradual and significant increase in seasonal IV coverage in the elderly (p for trend < 0.001). After 2006/07, IV coverage remained near 50%. Adjusting for baseline trends, there was significantly higher coverage in the general population in 2003/04 (p = 0.032) and 2005/06 (p = 0.018). The high coverage observed in the <15-year age group in season 2009/10 was also significant (p = 0.015).

Conclusions

IV coverage in the elderly population displayed an increasing trend, but the 75% WHO 2010 target was not met. This result indicates that influenza vaccination strategy should be improved to meet the ambitious WHO coverage goals. The major pandemic threats of the past decade had a modest but significant effect on seasonal influenza vaccination. There was an increase in vaccine uptake proportion in the general population in 2003/04 and in 2005/06, and in individuals <15 years old in 2009/10.

Survey of Australian inpatients on vaccination status and perceptions of influenza vaccination

OBJECTIVE

To assess vaccination status, potential influences upon vaccination status, and attitudes and beliefs about vaccination among hospital inpatients.

DESIGN

This prospective, cross-sectional audit assessed vaccination status for important communicable diseases, patient perceptions about the influenza vaccination, and possible influences on vaccination status. Information was collected during face-to-face interviews using a structured questionnaire.

SETTING

This study was undertaken in a general teaching hospital in suburban Adelaide, South Australia.

PARTICIPANTS

The study participants comprised a convenience sample of 50 inpatients at the hospital from April 25, 2011, to May 18, 2011.

INTERVENTION

Interview and structured questionnaire at bedside.

MAIN OUTCOME MEASURES

Vaccination status for seasonal influenza, pneumococcal vaccine, diphtheriatetanus-pertussis/diphtheria-tetanus vaccination, herpes zoster virus, and hepatitis B were assessed for inpatients. Qualitative information regarding patient perceptions about the influenza vaccination was also surveyed. Possible influences on vaccination status including comorbidities or high-risk conditions, area of residence, age, and gender were also assessed.

RESULTS

The self-reported vaccination rates were: seasonal influenza vaccine 2010 (64%), seasonal influenza vaccine 2011 (52%), pneumococcal vaccine (46%), diphtheria-tetanuspertussis/ diphtheria-tetanus vaccination (70%), herpes zoster vaccination (34%), and hepatitis B vaccination (40%). Vaccination was significantly more common among those older than 64 years of age (P = 0.01), with 46% of patients older than 64 years vaccinated against influenza. There was no significant association between vaccination status and other characteristics such as gender, number of risk factors, recent hospital admission, and living in a residential facility. Regarding perceptions toward the influenza vaccine, the only factor associated with significantly increased likelihood of vaccination was self-reported risk perception (P = 0.03). The majority of patients described positive views about influenza vaccine efficacy and expressed willingness to receive the vaccine if recommended by their doctor.

CONCLUSIONS

In this audit, vaccination status appeared to be age-dependent, with higher vaccination coverage among older patients. Those who perceived that the influenza vaccine is associated with many side effects were less likely to be vaccinated. Pharmacists may have a role in encouraging older adults to be vaccinated.

A review of influenza: implications for the geriatric population

The influenza virus is a significant cause of morbidity and mortality each year in the United States, and is a major public health problem. Individuals aged 65 years and older comprise a sizeable population subgroup at high risk of infection and subsequent complications. Although influenza may cause substantial morbidity and mortality across the age spectrum, it becomes particularly problematic for those older than 65. This article presents an overview of influenza, with a focus on how the influenza virus has particular implications for the geriatric population.

Effects of annual influenza vaccination on mortality and hospitalization in elderly patients with ischemic heart disease: a nationwide population-based study

OBJECTIVE

The effects of influenza vaccination on ischemic heart disease (IHD) patients remain controversial. The purpose of this study was to evaluate the effects of influenza vaccination on all-cause mortality and hospitalization for cardiovascular disease in elderly IHD patients.

METHODS

Elderly patients (>65 years old) with IHD, including ischemic heart failure and coronary artery disease between January 1997 and September 2002 were identified by using the Taiwan National Health Insurance Research Database. The association between influenza vaccination and all-cause mortality and hospitalization due to cardiovascular disease was analyzed.

RESULTS

We included 5048 patients. During the influenza season, influenza vaccination was associated with a reduced risk of all-cause mortality [hazard ratio (HR), 0.42; 95% confidence interval (CI) 0.35-0.49] and hospitalization for cardiovascular disease (HR, 0.84; 95% CI, 0.76-0.93). During the non-influenza season, vaccination was associated with a reduced risk of mortality (HR, 0.78; 95% CI, 0.68-0.90) in elderly IHD patients.

CONCLUSION

Influenza vaccination was associated with a reduced risk of all-cause mortality in elderly IHD patients throughout the whole year, as well as a reduced risk of hospitalization during the influenza season.

A prospective, randomized, open-label trial comparing the safety and efficacy of trivalent live attenuated and inactivated influenza vaccines in adults 60 years of age and older

BACKGROUND

Although influenza is a major public health concern among adults ≥60 years of age, few large, prospective studies of influenza vaccines have been conducted in this population. The goal of the present study was to directly compare the safety and efficacy of LAIV and TIV in adults ≥60 years of age.

MATERIALS AND METHODS

A prospective, randomized, open-label, multicenter trial was conducted in South Africa. In March-April 2002, 3009 community-dwelling ambulatory adults 60-95 years of age were randomized 1:1 to receive a single dose of LAIV or TIV. Surveillance for influenza illness was conducted through November. Serum antibody titers were evaluated in all participants, and interferon-γ enzyme-linked immunosorbent spot assay responses were evaluated in a cohort of subjects. Solicited reactogenicity and adverse events were monitored for days 0-10 postvaccination; serious adverse events were monitored for the entire study.

RESULTS

Influenza illness caused by vaccine-matched strains was detected in 0.8% (12/1494) and 0.5% (8/1488) of LAIV and TIV recipients, respectively; the relative efficacy of LAIV vs TIV was -49% (95% CI: -259, 35). As expected, greater serum antibody responses were seen with TIV, and greater cellular responses were seen with LAIV (although not for influenza B). Among subjects with culture-confirmed influenza illness, post hoc analyses revealed trends toward less feverishness (LAIV, 14%; TIV, 46%; P=0.05) and less fever (LAIV, 9%; TIV, 31%; P=0.16) among LAIV recipients. In each treatment group, 38-39% and 24-25% of subjects had baseline hemagglutination inhibition titers of ≤4 for A/H1 and A/H3, but 7 of 8 TIV cases and 7 of 12 LAIV cases of matched-strain influenza occurred among these subjects. Runny nose/nasal congestion (+13%), cough (+5%), sore throat (+5%), lethargy (+3%), and decreased appetite (+2%) were reported by more LAIV vs TIV recipients. Injection site reactions were reported by 27% of TIV recipients. SAEs were reported by a similar proportion of LAIV and TIV recipients (9% vs 8%).

CONCLUSIONS

Given the low incidence of influenza in both groups, no conclusions were possible regarding the relative efficacy of LAIV and TIV. There was a trend toward less feverishness/fever among LAIV recipients who developed influenza compared with TIV recipients with influenza, consistent with results from studies comparing the vaccines in children. A disproportionate number of influenza illnesses occurred among baseline seronegative subjects, particularly for those receiving TIV, which suggests that this subgroup has the greatest need for improved influenza vaccination. The safety profiles of LAIV and TIV were consistent with results from previous studies in older adults and no significant safety concerns were identified. clinicaltrials.gov identifier, NCT00192413.

Structural basis of influenza virus neutralization

Although seasonal influenza vaccines play a valuable role in reducing the spread of virus at the population level, ongoing viral evolution to evade immune responses remains problematic. No current vaccines elicit enduring protection in the face of emerging and re-emerging influenza viruses that are rapidly undergoing antigenic drift. Eliciting broadly cross-neutralizing antibody (nAb) responses against influenza virus is a crucial goal for seasonal and pandemic influenza vaccine preparation. Recent three-dimensional structure information obtained from crystallization of influenza antigens in complex with nAbs has provided a framework for interpreting antibody-based viral neutralization that should aid in the design of vaccine immunogens. Here, we will review current knowledge of the structure-based mechanisms contributing to the neutralization and neutralization escape of influenza viruses. We will also explore the potential for this structure-based approach to overcome the obstacles in developing the highly desired "universal" influenza vaccine.

Influenza vaccine supply and racial/ethnic disparities in vaccination among the elderly

BACKGROUND

The impact of vaccine shortages on disparities in influenza vaccination is uncertain.

PURPOSE

The objective of this research was to examine the association between influenza vaccine supply and racial/ethnic disparities in vaccination rates among elderly Medicare beneficiaries.

METHODS

Cross-sectional multivariable logistic regression analyses were performed in 2010 to examine whether racial/ethnic disparities in vaccination rates changed across two consecutive seasons: from (Period 1) 2000-2001 and 2001-2002 seasons through (Period 4) 2003-2004 and 2004-2005 seasons. Self-reported receipt of influenza vaccine across consecutive years was examined among community-dwelling non-Hispanic African-American (AA); non-Hispanic white (W); English-speaking Hispanic (EH); and Spanish-speaking Hispanic (SH) elderly enrolled in the Medicare Current Beneficiary Survey (unweighted n=2306-2504, weighted n=8.23-8.99 million for Periods 1 through 4).

RESULTS

During Periods 1 and 2, when vaccine supply increased nationally, adjusted racial/ethnic disparities in the influenza vaccination rate decreased by 1.8%-7.4% (W-AA disparity); 4.5%-6.6% (W-EH disparity); and 6.6%-11% (W-SH disparity) (all p<0.001). During Period 4, when vaccine supply declined, adjusted disparities in vaccination rates increased by 2.3% (W-AA disparity) and 6.1% (W-EH disparity) but decreased by 6.6% (W-SH disparity) probably due to a "floor effect" (constant low rates among SH; all p<0.001).

CONCLUSIONS

Improved vaccine supply was generally associated with reduced racial/ethnic disparities in influenza vaccination rates, whereas worse supply was associated with increased disparities. To avoid future widening of racial health disparities, policy options include stabilizing the vaccine supply and preferential delivery of vaccines to safety-net providers serving AA and Hispanic populations during a shortage.

Campaign, counseling and compliance with influenza vaccine among older persons

OBJECTIVES

Population aging raises concerns regarding the increases in the rates of morbidity and mortality that result from influenza and its complications. Although vaccination is the most important tool for preventing influenza, vaccination program among high-risk groups has not reached its predetermined aims in several settings. This study aimed to evaluate the impacts of clinical and demographic factors on vaccine compliance among the elderly in a setting that includes a well-established annual national influenza vaccination campaign.

METHODS

This cross-sectional study included 134 elderly patients who were regularly followed in an academic medical institution and who were evaluated for their influenza vaccination uptake within the last five years; in addition, the demographic and clinical characteristics and the reasons for compliance or noncompliance with the vaccination program were investigated.

RESULTS

In total, 67.1% of the participants received the seasonal influenza vaccine in 2009. Within this vaccination-compliant group, the most common reason for vaccine uptake was the annual nationwide campaign (52.2%; 95% CI: 41.4-62.9%); compared to the noncompliant group, a higher percentage of compliant patients had been advised by their physician to take the vaccine (58.9% vs. 34.1%; p<0.01).

CONCLUSION

The education of patients and health care professionals along with the implementation of immunization campaigns should be evaluated and considered by health authorities as essential for increasing the success rate of influenza vaccination compliance among the elderly.

Are standing order programs associated with influenza vaccination? - NNHS, 2004

BACKGROUND

Influenza vaccination coverage among nursing home residents has consistently been reported well below the Healthy People goals. We sought to determine if standing order programs (SOPs) in long-term care facilities are associated with greater influenza vaccination coverage among residents.

METHODS

The National Nursing Home Survey (2004) is cross-sectional. A total of 1152 US long-term care facilities were systematically sampled with probability proportional to number of beds. A total of 11,939 people aged 65 years or older residing in sampled long-term care facilities between August and December 2004 were randomly sampled. Influenza vaccination coverage of residents was obtained from facility records. Facility's immunization program included standing orders versus other (preprinted admission order, advance physician order, personal physician order, and no program). Multinomial logistic regression was used to examine the relationship between type of influenza immunization program and receipt of vaccination, adjusted for resident and facility confounders.

RESULTS

The proportion of residents aged 65 years or older who received influenza vaccination was 64%; 41% of residents lived in a facility with an SOP. Influenza vaccination coverage among residents residing in facilities with standing orders was 68% compared with 59% to 63% of residents in facilities with other program types. Logistic regression showed that standing order programs were independently associated with greater influenza vaccination coverage (66.7% versus 62.0%, P < .01).

CONCLUSION

This study indicates that residents in long-term care facilities having standing order programs for influenza were more likely to be immunized. More research needs to be done to understand how to facilitate adoption of these programs.

Effects of an ongoing epidemic on the annual influenza vaccination rate and vaccination timing among the Medicare elderly: 2000-2005

OBJECTIVES

We assessed short-term responsiveness of influenza vaccine demand to variation in timing and severity of influenza epidemics since 2000. We tested the hypothesis that weekly influenza epidemic activity is associated with annual and daily influenza vaccine receipt.

METHODS

We conducted cross-sectional survival analyses from the 2000-2001 to 2004-2005 influenza seasons among community-dwelling elderly using the Medicare Current Beneficiary Survey (unweighted n = 2280-2822 per season; weighted n = 7.7-9.7 million per season). The outcome variable was daily vaccine receipt. Covariates included the biweekly changes of epidemic and vaccine supply at 9 census-region levels.

RESULTS

In all 5 seasons, biweekly epidemic change was positively associated with overall annual vaccination (e.g., 2.7% increase in 2003-2004 season) as well as earlier vaccination timing (P < .01). For example, unvaccinated individuals were 5%-29% more likely to receive vaccination after a 100% biweekly epidemic increase.

CONCLUSIONS

Accounting for short-term epidemic responsiveness in predicting demand for influenza vaccination may improve vaccine distribution and the annual vaccination rate, and might assist pandemic preparedness planning.

Vaccination against classical influenza in health-care workers: self-protection and patient protection

BACKGROUND

Health-care workers are at risk of occupational exposure to influenza and can also transmit the disease to their patients.

METHODS

Selective literature review and description of the influenza vaccination program at the Frankfurt University Hospital.

RESULTS AND CONCLUSIONS

Many studies demonstrate that influenza vaccination for health-care workers lowers morbidity and mortality in their patients. Official immunization recommendations and free, voluntary immunization programs for health-care workers have been in existence for many years. Nevertheless, influenza vaccination rates are unacceptably low. Therefore, mandatory vaccination ought to be considered. In addition, infection-control measures (covering the mouth and nose with a mask, meticulous hand disinfection) should be rigorously observed in the hospital to prevent the nosocomial transmission of influenza and other infectious diseases. Vaccination rates might be improved if health-care workers were made aware that they themselves face a risk of infection.

Influenza vaccination and mortality: differentiating vaccine effects from bias

It is widely believed that influenza (flu) vaccination of the elderly reduces all-cause mortality, yet randomized trials for assessing vaccine effectiveness are not feasible and the observational research has been controversial. Efforts to differentiate vaccine effectiveness from selection bias have been problematic. The authors examined mortality before, during, and after 9 flu seasons in relation to time-varying vaccination status in an elderly California population in which 115,823 deaths occurred from 1996 to 2005, including 20,484 deaths during laboratory-defined flu seasons. Vaccine coverage averaged 63%; excess mortality when the flu virus was circulating averaged 7.8%. In analyses that omitted weeks when flu circulated, the odds ratio measuring the vaccination-mortality association increased monotonically from 0.34 early in November to 0.56 in January, 0.67 in April, and 0.76 in August. This reflects the trajectory of selection effects in the absence of flu. In analyses that included weeks with flu and adjustment for selection effects, flu season multiplied the odds ratio by 0.954. The corresponding vaccine effectiveness estimate was 4.6% (95% confidence interval: 0.7, 8.3). To differentiate vaccine effects from selection bias, the authors used logistic regression with a novel case-centered specification that may be useful in other population-based studies when the exposure-outcome association varies markedly over time.

Development and psychometric validation of a self-administered questionnaire assessing the acceptance of influenza vaccination: the Vaccinees' Perception of Injection (VAPI) questionnaire

BACKGROUND

Influenza is among the most common infectious diseases. The main protection against influenza is vaccination. A self-administered questionnaire was developed and validated for use in clinical trials to assess subjects' perception and acceptance of influenza vaccination and its subsequent injection site reactions (ISR).

METHODS

The VAPI questionnaire was developed based on interviews with vaccinees. The initial version was administered to subjects in international clinical trials comparing intradermal with intramuscular influenza vaccination. Item reduction and scale construction were carried out using principal component and multitrait analyses (n = 549). Psychometric validation of the final version was conducted per country (n = 5,543) and included construct and clinical validity and internal consistency reliability. All subjects gave their written informed consent before being interviewed or included in the clinical studies.

RESULTS

The final questionnaire comprised 4 dimensions ("bother from ISR"; "arm movement"; "sleep"; "acceptability") grouping 16 items, and 5 individual items (anxiety before vaccination; bother from pain during vaccination; satisfaction with injection system; willingness to be vaccinated next year; anxiety about vaccination next year). Construct validity was confirmed for all scales in most of the countries. Internal consistency reliability was good for all versions (Cronbach's alpha ranging from 0.68 to 0.94), as was clinical validity: scores were positively correlated with the severity of ISR and pain.

CONCLUSION

The VAPI questionnaire is a valid and reliable tool, assessing the acceptance of vaccine injection and reactions following vaccination.

Prevalence of influenza vaccination and pneumococcal vaccination in elderly and high-risk patients seen in a university general medicine clinic

Charts of 240 unselected patients (149 women and 91 men), mean age 74 +/- 7 years (range, 64-95 years), seen in a university general medicine clinic at Westchester Medical Center/New York Medical College between April 2004 and April 2007 were reviewed for the use of influenza vaccination and pneumococcal vaccination. Of the 240 patients, 108 (45%) had cardiovascular disease, 183 (76%) had hypertension, 70 (29%) had diabetes mellitus, 32 (13%) had chronic pulmonary disease, 30 (13%) had cancer, 26 (11%) had chronic renal disease, and 19 (8%) had no chronic illness. Of the 240 patients, 24 (10%) refused influenza vaccination and two (1%) had a hypersensitivity to eggs. Of 240 patients, 18 (8%) refused pneumococcal vaccination. Of 94 patients who did not refuse influenza vaccination or were allergic to eggs during the winter season of October 2004 through January 2005, 58 (62%) had influenza vaccination. Ninety-two of 172 patients (54%) had influenza vaccination during October 2005 through January 2006. Ninety-seven of 136 patients (71%) had influenza vaccination during October 2006 through January 2007. Of 222 patients, 111 (50%) had pneumococcal vaccination during 2004 through 2007.

Avian influenza: update on pathogenesis and laboratory diagnosis

In the past 10 years, two respiratory viral infections-severe acute respiratory syndrome (SARS) and H5N1-have emerged that have led to a high mortality among infected individuals. Laboratory investigations have demonstrated that these two emerging infections have similar features; and understanding the pathophysiological mechanisms of the disease causation will lead to insight into standard and novel treatments for these infections. In this review we highlight the similarities and differences of SARS and H5N1, and emphasize the importance of appropriate sampling for laboratory diagnosis of the latter.

Coverage and predictors of influenza vaccination among adults living in a large metropolitan area in Spain: a comparison between the immigrant and indigenous populations

This study sought to evaluate influenza vaccination coverage in Madrid (Spain). Coverages were estimated for vaccine target groups and special attention was placed on the immigrant population. Individual data from 7341 adults included in the Madrid City Health Survey conducted in 2005 was used. Overall influenza vaccination coverage was 24%. Compliance with age-based influenza vaccine guidelines (>or=65 years) was 63.9%, among those<65 years who had an associated chronic condition, it was 37.9% and 24.1% among HCWs. Immigrants accounted for 12.4% of the sample. Overall crude coverage was significantly lower among immigrants than among the indigenous population (11.2% vs. 25.9%), but once the multivariate analysis had been performed, the association became non-significant. In conclusion, it must be said that all the available evidence indicates an inadequate level of influenza vaccination coverage among HCWs and high-risk subjects <65 years. On the other hand, coverages among subjects aged >or=65 years are acceptable and there is no observable difference in vaccine use between immigrants and indigenous subjects. Strategies that have demonstrated their effectiveness in enhancing vaccination coverages should be applied in Madrid.

Immunological outcomes of exercise in older adults

Aging is associated with a dysregulation of the immune system known as immunosenescence. Immunosenescence involves cellular and molecular alterations that impact both innate and adaptive immunity, leading to increased incidences of infectious disease morbidity and mortality as well as heightened rates of other immune disorders such as autoimmunity, cancer, and inflammatory conditions. While current data suggests physical activity may be an effective and logistically easy strategy for counteracting immunosenescence, it is currently underutilized in clinical settings. Long-term, moderate physical activity interventions in geriatric populations appear to be associated with several benefits including reduction in infectious disease risk, increased rates of vaccine efficacy, and improvements in both physical and psychosocial aspects of daily living. Exercise may also represent a viable therapy in patients for whom pharmacological treatment is unavailable, ineffective, or inappropriate. The effects of exercise impact multiple aspects of immune response including T cell phenotype and proliferation, antibody response to vaccination, and cytokine production. However, an underlying mechanism by which exercise affects numerous cell types and responses remains to be identified. Given this evidence, an increase in the use of physical activity programs by the healthcare community may result in improved health of geriatric populations.

Effectiveness of influenza vaccine in the community-dwelling elderly

BACKGROUND

Reliable estimates of the effectiveness of influenza vaccine among persons 65 years of age and older are important for informed vaccination policies and programs. Short-term studies may provide misleading pictures of long-term benefits, and residual confounding may have biased past results. This study examined the effectiveness of influenza vaccine in seniors over the long term while addressing potential bias and residual confounding in the results.

METHODS

Data were pooled from 18 cohorts of community-dwelling elderly members of one U.S. health maintenance organization (HMO) for 1990-1991 through 1999-2000 and of two other HMOs for 1996-1997 through 1999-2000. Logistic regression was used to estimate the effectiveness of the vaccine for the prevention of hospitalization for pneumonia or influenza and death after adjustment for important covariates. Additional analyses explored for evidence of bias and the potential effect of residual confounding.

RESULTS

There were 713,872 person-seasons of observation. Most high-risk medical conditions that were measured were more prevalent among vaccinated than among unvaccinated persons. Vaccination was associated with a 27% reduction in the risk of hospitalization for pneumonia or influenza (adjusted odds ratio, 0.73; 95% confidence interval [CI], 0.68 to 0.77) and a 48% reduction in the risk of death (adjusted odds ratio, 0.52; 95% CI, 0.50 to 0.55). Estimates were generally stable across age and risk subgroups. In the sensitivity analyses, we modeled the effect of a hypothetical unmeasured confounder that would have caused overestimation of vaccine effectiveness in the main analysis; vaccination was still associated with statistically significant--though lower--reductions in the risks of both hospitalization and death.

CONCLUSIONS

During 10 seasons, influenza vaccination was associated with significant reductions in the risk of hospitalization for pneumonia or influenza and in the risk of death among community-dwelling elderly persons. Vaccine delivery to this high-priority group should be improved.