Recent health-related quality of life, but not change, predicted mortality and healthcare utilization.

OBJECTIVE: To assess whether change in HRQOL over a seven-year period was associated with subsequent mortality and hospitalization, after adjusting for important covariates, in a cohort of U.S. Veterans. METHODS: We used data from a cohort of Veterans who completed a HRQOL survey in 1998 (Short-Form 36 for Veterans [SF-36V]) and a 2006 follow-up (SF-12V) HRQOL survey and SF12V scores were calculated at both time-points. We used logistic regression analyses to model the relationship between changes in the SF12-V physical component (PCS) and mental health component (MCS) scores and 1-year hospitalization and 1-year and 3.3-year mortality after the 2006 follow-up survey. RESULTS: 13,900 participants provided data for both the initial and follow-up surveys. We found no significant associations between changes in PCS or MCS and one-year hospitalization after adjusting for follow-up HRQOL and other covariates. We found significant but relatively weak associations between changes in MCS and our mortality outcomes. CONCLUSION: Given the follow-up MCS and PCS, change in PCS over the previous 7 years added little information for predicting mortality and hospitalization Although the change in MCS added some information for predicting mortality. Therefore, knowledge of patient's current HRQOL generally provides meaningful information for predicting subsequent mortality and hospitalization.

Effect of High-Dose Trivalent vs Standard-Dose Quadrivalent Influenza Vaccine on Mortality or Cardiopulmonary Hospitalization in Patients With High-risk Cardiovascular Disease: A Randomized Clinical Trial.

Importance: Influenza is temporally associated with cardiopulmonary morbidity and mortality among those with cardiovascular disease who may mount a less vigorous immune response to vaccination. Higher influenza vaccine dose has been associated with reduced risk of influenza illness. Objective: To evaluate whether high-dose trivalent influenza vaccine compared with standard-dose quadrivalent influenza vaccine would reduce all-cause death or cardiopulmonary hospitalization in high-risk patients with cardiovascular disease. Design, Setting, and Participants: Pragmatic multicenter, double-blind, active comparator randomized clinical trial conducted in 5260 participants vaccinated for up to 3 influenza seasons in 157 sites in the US and Canada between September 21, 2016, and January 31, 2019. Patients with a recent acute myocardial infarction or heart failure hospitalization and at least 1 additional risk factor were eligible. Interventions: Participants were randomly assigned to receive high-dose trivalent (n = 2630) or standard-dose quadrivalent (n = 2630) inactivated influenza vaccine and could be revaccinated for up to 3 seasons. Main Outcomes and Measures: The primary outcome was the time to the composite of all-cause death or cardiopulmonary hospitalization during each enrolling season. The final date of follow-up was July 31, 2019. Vaccine-related adverse events were also assessed. Results: Among 5260 randomized participants (mean [SD] age, 65.5 [12.6] years; 3787 [72%] men; 3289 [63%] with heart failure) over 3 influenza seasons, there were 7154 total vaccinations administered and 5226 (99.4%) participants completed the trial. In the high-dose trivalent vaccine group, there were 975 primary outcome events (883 hospitalizations for cardiovascular or pulmonary causes and 92 deaths from any cause) among 884 participants during 3577 participant-seasons (event rate, 45 per 100 patient-years), whereas in the standard-dose quadrivalent vaccine group, there were 924 primary outcome events (846 hospitalizations for cardiovascular or pulmonary causes and 78 deaths from any cause) among 837 participants during 3577 participant-seasons (event rate, 42 per 100 patient-years) (hazard ratio, 1.06 [95% CI, 0.97-1.17]; P = .21). In the high-dose vs standard-dose groups, vaccine-related adverse reactions occurred in 1449 (40.5%) vs 1229 (34.4%) participants and severe adverse reactions occurred in 55 (2.1%) vs 44 (1.7%) participants. Conclusions and Relevance: In patients with high-risk cardiovascular disease, high-dose trivalent inactivated influenza vaccine, compared with standard-dose quadrivalent inactivated influenza vaccine, did not significantly reduce all-cause mortality or cardiopulmonary hospitalizations. Influenza vaccination remains strongly recommended in this population. Trial Registration: ClinicalTrials.gov Identifier: NCT02787044.

Association of Influenza-like Illness Activity With Hospitalizations for Heart Failure: The Atherosclerosis Risk in Communities Study.

Importance: Influenza is associated with an increased risk of cardiovascular events, but to our knowledge, few studies have explored the temporal association between influenza activity and hospitalizations, especially those caused by heart failure (HF). Objective: To explore the temporal association between influenza activity and hospitalizations due to HF and myocardial infarction (MI). We hypothesized that increased influenza activity would be associated with an increase in hospitalizations for HF and MI among adults in the community. Design, Setting, and Participants: As part of the community surveillance component of the Atherosclerosis Risk in Communities (ARIC) study, a population-based study with hospitalizations sampled from 4 US communities, data were collected from 451 588 adults aged 35 to 84 years residing in the ARIC communities from annual cross-sectional stratified random samples of hospitalizations during October 2010 to September 2014. Exposures: Monthly influenza activity, defined as the percentage of patient visits to sentinel clinicians for influenza-like illness by state, as reported by the Centers for Disease Control and Prevention Surveillance Network. Main Outcomes and Measures: The monthly frequency of MI hospitalizations (n = 3541) and HF hospitalizations (n = 4321), collected through community surveillance and adjudicated as part of the ARIC Study. Results: Between October 2010 and September 2014, 2042 (47.3%) and 1599 (45.1%) of the sampled patients who were hospitalized for HF and MI, respectively, were women and 2391 (53.3%) and 2013 (57.4%) were white, respectively. A 5% monthly absolute increase in influenza activity was associated with a 24% increase in HF hospitalization rates, standardized to the total population in each community, within the same month after adjusting for region, season, race/ethnicity, sex, age, and number of MI/HF hospitalizations from the month before (incidence rate ratio, 1.24; 95% CI, 1.11-1.38; P < .001), while overall influenza activity was not significantly associated with MI hospitalizations (incidence rate ratio, 1.02; 95% CI, 0.90-1.17; P = .72). Influenza activity in the months before hospitalization was not associated with either outcome. Our model suggests that in a month with high influenza activity, approximately 19% of HF hospitalizations (95% CI, 10%-28%) could be attributable to influenza. Conclusions and Relevance: Influenza activity was temporally associated with an increase in HF hospitalizations across 4 influenza seasons. These data suggest that influenza may contribute to the risk of HF hospitalization in the general population.

High-dose influenza vaccine to reduce clinical outcomes in high-risk cardiovascular patients: Rationale and design of the INVESTED trial.

BACKGROUND: Influenza leads to significant cardiopulmonary morbidity and mortality-particularly in patients with cardiovascular disease-that may be prevented with a standard influenza vaccine. However, patients with cardiovascular conditions have a reduced immune response to influenza vaccine, potentially resulting in reduced effectiveness for preventing clinical events. High-dose vaccine augments immune response in cardiac patients, suggesting that a high-dose influenza vaccination strategy may further reduce morbidity and mortality. Alternatively, broader coverage with an influenza vaccine containing an increased number of viral strains is an alternative strategy without direct evaluation. RESEARCH DESIGN AND METHODS: INfluenza Vaccine to Effectively Stop Cardio Thoracic Events and Decompensated heart failure (INVESTED) is a pragmatic, randomized, double-blind, parallel-group, active-controlled trial comparing the effectiveness of an annual vaccination strategy of high-dose trivalent versus standard-dose quadrivalent influenza vaccine in patients with a history of recent heart failure or myocardial infarction hospitalization. The trial will enroll approximately 9,300 patients over 4 influenza seasons. The primary hypothesis is that high-dose influenza vaccine will reduce the composite outcome of all-cause mortality and hospitalization from a cardiovascular or pulmonary cause compared with standard-dose influenza vaccine within each enrolling season. Approximately 1,300 primary outcome events will provide >90% power to detect an 18% relative risk reduction at a 2-sided α level of .05. CONCLUSION: INVESTED is the largest and longest study to assess whether high-dose influenza vaccine is superior to standard-dose influenza vaccine in reducing cardiopulmonary events in a high-risk cardiovascular population (ClinicalTrials.gov Identifier: NCT02787044).

Comparison of Side Effects of the 2015-2016 High-Dose, Inactivated, Trivalent Influenza Vaccine and Standard Dose, Inactivated, Trivalent Influenza Vaccine in Adults ≥65 Years.

BACKGROUND: High-dose, inactivated, trivalent influenza vaccine (HD) is associated with higher rates of side effects than standard dose (SD) vaccine, which may represent a barrier to use. METHODS: We surveyed subjects ≥65 years who received either HD or SD vaccine at the Minneapolis Veteran Affairs Health Care System clinics on October 27, 28, or 29, 2015. Research assistants conducted a 17-item telephone survey of influenza vaccine recipients to inquire about self-reported health and symptoms experienced the week after vaccination. RESULTS: A total of 547 HD recipients and 541 SD recipients responded to the survey. The 2 groups were similar at baseline with respect to age, gender, and presence of high-risk medical conditions. At least ≥95% of individuals in both HD and SD groups reported that their overall health was the same or better than usual during the week after vaccination. Thirty-seven percent of HD recipients and 22% of SD recipients reported a local or systemic side effect (P < .001), most of which were mild to moderate. Only 7 of 547 (1.3%) HD recipients and 3 of 541 (0.6%) SD recipients reported a severe side effect (P = .34). There was no significant difference in healthcare visits between the groups. CONCLUSIONS: Side effects were more common among subjects ≥65 years who received HD influenza vaccine compared with SD vaccine. These side effects were well tolerated and were not associated with impairment of general health status. These findings should reassure patients and their providers of the safety and tolerability of the HD influenza vaccine.

Effectiveness of A(H1N1)pdm09 influenza vaccine in adults recommended for annual influenza vaccination.

INTRODUCTION: Because of variability in published A(H1N1)pdm09 influenza vaccine effectiveness estimates, we conducted a study in the adults belonging to the risk groups to assess the A(H1N1)pdm09 MF59-adjuvanted influenza vaccine effectiveness. METHODS: VE against influenza and/or pneumonia was assessed in the cohort study (n>25000), and vaccine effectiveness against laboratory-confirmed A(H1N1)pdm09 influenza was assessed in a matched case-control study (16 pairs). Odds ratios (OR) and their 95% confidence intervals (95% CI) were calculated by using multivariate logistic regression; vaccine effectiveness was estimated as (1-odds ratio)*100%. RESULTS: Vaccine effectiveness against laboratory-confirmed A(H1N1)pdm09 influenza and influenza and/or pneumonia was 98% (84-100%) and 33% (2-54%) respectively. The vaccine did not prevent influenza and/or pneumonia in 18-59 years old subjects, and was 49% (16-69%) effective in 60 years and older subjects. CONCLUSIONS: Even though we cannot entirely rule out that selection bias, residual confounding and/or cross-protection has played a role, the present results indicate that the MF59-adjuvanted A(H1N1)pdm09 influenza vaccine has been effective in preventing laboratory-confirmed A(H1N1)pdm09 influenza and influenza and/or pneumonia, the latter notably in 60 years and older subjects.

Maternal safety of trivalent inactivated influenza vaccine in pregnant women.

OBJECTIVE: To estimate the risks for medically attended events occurring within 42 days of receiving trivalent inactivated influenza vaccine and to evaluate specific risks of first-trimester vaccination. METHODS: This retrospective observational cohort study compared rates of medically attended adverse events in trivalent inactivated influenza-vaccinated and unvaccinated pregnant women in the Vaccine Safety Datalink. Using a Poisson distribution and log link, we calculated maternal adjusted incident rate ratios for composite safety outcomes for the full cohort and the subset vaccinated during the first trimester. RESULTS: The cohort included 75,906 vaccinated (28.4% in the first trimester) and 147,992 unvaccinated women matched by age, site, and pregnancy start date. In the first 3 days after vaccination, trivalent inactivated influenza vaccine was not associated with increased risk of specified medically attended events, including allergic reactions, cellulitis, and seizures (full cohort adjusted incident rate ratio 1.12, 95% confidence interval [CI] 0.81-1.55; P=.48; first-trimester adjusted incident rate ratio .97, 95% CI 0.53-1.78; P=.93). In the first 42 days, no incident cases of Guillain-Barré syndrome, optic neuritis, transverse myelitis, or Bells palsy were identified. Trivalent inactivated influenza vaccine was not associated with thrombocytopenia (full cohort adjusted incident rate ratio 0.90, 95% CI 0.68--1.19; P=.45; first-trimester adjusted incident rate ratio 0.56, 95% CI 0.22-1.39; P=.21) or an acute neurologic event (full cohort adjusted incident rate ratio 0.92, 95% CI 0.54-1.6; P=.75; first-trimester adjusted incident rate ratio 1.05, 95% CI 0.46-2.38; P=.91). CONCLUSIONS: Receipt of trivalent inactivated influenza vaccine during pregnancy was not associated with increased risk of adverse events in the 42 days after vaccination, supporting its safety for the mother.

Innovative approaches for understanding seasonal influenza vaccine declination in healthcare personnel support development of new campaign strategies.

OBJECTIVE: The main objectives of our study were to explore reasons for seasonal influenza vaccine acceptance and declination in employees of a large integrated healthcare system and to identify underlying constructs that influence acceptance versus declination. Secondary objectives were to determine whether vaccine acceptance varied by hospital location and to identify facility-level measures that explained variability. DESIGN: A national health promotion survey of employees was conducted that included items on vaccination in the 2009-2010 influenza season. The survey was administered with two other institutional surveys in a stratified fashion: approximately 40% of participating employees were randomly assigned to complete the health promotion survey. SETTING: National single-payer healthcare system with 152 hospitals. PARTICIPANTS: Employees of the healthcare system in 2010 who responded to the survey. METHODS: Factor analysis was used to identify underlying constructs that influenced vaccine acceptance versus declination. Mean factor scores were examined in relation to demographic characteristics and occupation. Multilevel logistic regression models were used to determine whether vaccine acceptance varied by location and to identify facility-level measures that explained variability. RESULTS: Four factors were identified related to vaccine declination and were labeled as (1) "don't care," (2) "don't want," (3) "don't believe," and (4) "don't know." Significant differences in mean factor scores existed by demographic characteristics and occupation. Vaccine acceptance varied by location, and vaccination rates in the previous year were an important facility-level predictor. CONCLUSIONS: Results should guide interventions that tailor messages on the basis of particular reasons for declination. Occupation-specific and culturally appropriate messaging should be considered. Continued efforts will be taken to better understand how workplace context influences vaccine acceptance.

Identifying barriers to adult pneumococcal vaccination: an NFID task force meeting.

Pneumococcal infection is common in adults, and invasive disease is associated with a high mortality rate. Pneumococcal polysaccharide vaccine can prevent invasive pneumococcal disease and is recommended for people aged ≥ 65 years and for younger adults with high-risk chronic conditions; however, vaccination rates are suboptimal in all of these groups. A multidisciplinary task force meeting examined ways to increase vaccination rates in the target populations. Barriers to vaccination include lack of awareness of the disease or vaccine among vaccination candidates and health care providers, failure to assume responsibility for vaccination, competing priorities, incomplete or inaccessible documentation of previous vaccines, and health care system delivery challenges. Efforts to address these barriers should use appropriate methods. For example, potential vaccine recipients might be motivated by a message from a community leader, whereas health care providers are more apt to offer a vaccine when reminded that it is a recommended best practice. All health care providers need to accept responsibility for vaccination so that this preventive measure becomes a high priority in the care of patients at risk for serious pneumococcal infection.

Agreement between Internet-based self- and proxy-reported health care resource utilization and administrative health care claims.

OBJECTIVES: Although Internet-based surveys are becoming more common, little is known about agreement between administrative claims data and Internet-based survey self- and proxy-reported health care resource utilization (HCRU) data. This analysis evaluated the level of agreement between self- and proxy-reported HCRU data, as recorded through an Internet-based survey, and administrative claims-based HCRU data. METHODS: The Child and Household Influenza-Illness and Employee Function study collected self- and proxy-reported HCRU data monthly between November 2007 and May 2008. Data included the occurrence and number of visits to hospitals, emergency departments, urgent care centers, and outpatient offices for a respondent's and his or her household members' care. Administrative claims data from the MarketScan® Databases were assessed during the same time and evaluated relative to survey-based metrics. Only data for individuals with employer-sponsored health care coverage linkable to claims were included. The Kappa (κ) statistic was used to evaluate visit concordance, and the intraclass correlation coefficient was used to describe frequency consistency. RESULTS: Agreement for presence of a health care visit and the number of visits were similar for self- and proxy-reported HCRU data. There was moderate to substantial agreement related to health care visit occurrence between survey-based and claims-based HCRU data for inpatient, emergency department, and office visits (κ: 0.47-0.77). There was less agreement on health care visit frequencies, with intraclass correlation coefficient values ranging from 0.14 to 0.71. CONCLUSIONS: This study's agreement values suggest that Internet-based surveys are an effective method to collect self- and proxy-reported HCRU data. These results should increase confidence in the use of the Internet for evaluating disease burden.

Cost-effectiveness of a recommendation of universal mass vaccination for seasonal influenza in the United States.

OBJECTIVES: We evaluated the cost-effectiveness of universal mass vaccination (UMV) against influenza compared with a targeted vaccine program (TVP) for selected age and risk groups in the United States. METHODS: We modeled costs and outcomes of seasonal influenza with UMV and TVP, taking a societal perspective. The US population was stratified to model age-specific (< 5, 5-17, 18-49, 50-64, and 65+ years) vaccine coverage and efficacy. Probability of influenza-related illness (ILI) and complications, health-care utilization, costs, and survival were estimated. For a season's intervention, ILI cases in that year, lifetime costs (2008 US$), and quality-adjusted life years (QALYs) lost (both discounted at 3% per annum) were calculated for each policy and used to derive incremental cost-effectiveness ratios. A range of sensitivity and alternative-scenario analyses were conducted. RESULTS: In base-case analyses, TVP resulted in 63 million ILI cases, 859,000 QALYs lost, and $114.5 billion in direct and indirect costs; corresponding estimates for UMV were 61 million cases, 825,000 QALYs lost, and $111.4 billion. UMV was therefore estimated to dominate TVP, saving $3.1 billion and 34,000 QALYs. In probabilistic sensitivity analyses, UMV was dominant in 82% and dominated in 0% of iterations. In alternative-scenario analyses, UMV dominated TVP when lower estimates of vaccine coverage were used. Lower estimates of ILI risk among unvaccinated, vaccine effectiveness, and risk of complications resulted in ICERs of $2800, $8100, and $15,900 per QALY gained, respectively, for UMV compared with TVP. CONCLUSIONS: UMV against seasonal influenza is cost saving in the United States under reasonable assumptions for coverage, cost, and efficacy.

Cost-effectiveness and socio-economic aspects of childhood influenza vaccination.

Children have high rates of healthcare utilization due to influenza. In addition, children also transmit influenza to others in their households and the community. The costs of influenza in children include the direct medical care costs from increased outpatient visits and hospitalizations, and also indirect costs due to productivity losses especially for their parents and due to transmission of the virus to others. A variety of studies using different methods and assumptions have assessed the cost-effectiveness of influenza vaccination of children, and many find that vaccination is either cost saving or cost effective.

Telephone survey assessment of household patterns of influenza vaccination, Twin Cities seven county metro area, 2008-2009.

Major national surveys do not collect the influenza vaccination status of all household members, thus limiting current understanding of household influenza vaccination patterns. In an early 2009 telephone survey of 800 households in the metropolitan Minneapolis-St Paul area, household respondents reported the age, gender, and 2008-2009 seasonal influenza vaccination status of all household members. After poststratification to adjust for nonresponse, the full household influenza vaccination rate for multiperson households is 35.2%, partial household influenza vaccination rate is 39.9% and the rate of complete household nonvaccination is 24.9%. Full household influenza vaccination is more common in households with an elderly resident, intermediate in households with a child under 5 years of age, and less common in the remaining households. No household members are vaccinated in approximately 10% of multiperson households with either an elderly adult or young child; the corresponding rate in other households is 32.8%. An estimated 51.4% of households with children over 1 year of age have all children vaccinated against influenza; 43.5% of households with children had no children vaccinated against influenza. Households with younger children are more likely to have all children vaccinated and less likely to have no children vaccinated. We believe this is the first study to describe the prevalence of household influenza vaccination patterns. Continued efforts to monitor and increase household vaccination may be a valuable strategy to protect individuals and communities from influenza.

Attending work while sick: implication of flexible sick leave policies.

OBJECTIVE: To examine the impact of various flexible sick leave policies (FSLPs) on workplace attendance of employees with self-reported "severe" influenza-like-illness (ILI) symptoms. METHODS: This is a prospective study of employees from three US employers, which involved collection of information on employees' access to FSLPs and monthly experience with ILI and workplace attendance from November 2007 to April 2008. Multivariate analyses were used to estimate the impact of FSLPs on employees' workplace attendance while they were experiencing severe ILI symptoms. RESULTS: Among 793 employees with ILI, the average duration of severe ILI symptoms was 3.0 days. Most employees (71.9%) attended work with severe ILI symptoms, for an average of 1.3 days. Employees who could telework had a 29.7% lower rate of attending work with severe ILI symptoms (P = 0.026). CONCLUSIONS: Employers that implement teleworking policies may be able to reduce employee-to-employee transmission of respiratory illness, including seasonal and pandemic influenza.

Employees' willingness to pay to prevent influenza.

OBJECTIVES: To quantify employees' preferences, as measured by willingness to pay, to prevent influenza in themselves and in their child and adult household members and to examine factors associated with willingness to pay. STUDY DESIGN: Prospective observational cohort study of a convenience sample of employees from 3 large US employers. Participants had at least 1 child (< or = 17 years) living in their household for at least 4 days per week. METHODS: Each month from November 2007 to April 2008, employees completed Web-based surveys regarding acute respiratory illness in their household. In the final survey, employees were presented with descriptions of influenza and questions regarding their willingness to pay to prevent influenza. Factors associated with willingness to pay were examined using multivariate ordinary least squares regression analysis of the log of willingness to pay. RESULTS: Among 2006 employees, 31.3% were female, the mean age was 41.7 years, 85.3% were of white race/ethnicity, and the mean household size was 4.0. Employees' median (mean) willingness to pay to prevent influenza was $25 ($72) for themselves, $25 ($82) for their adult household members, and $50 ($142) (P <.01) for children. However, influenza vaccination rates were approximately equal for children (27.5%), employees (31.5%), and other adult household members (24.5%). This finding may be explained by barriers such as cost, dislike of vaccinations, and disagreement with national influenza vaccination recommendations, which were significantly associated with lower willingness to pay for prevention of influenza (P <.05). CONCLUSION: Employees expressed a stronger preference to prevent influenza in their children than in themselves or other household members; however, modifiable barriers depress vaccination rates.

Effect of influenza-like illness and other wintertime respiratory illnesses on worker productivity: The child and household influenza-illness and employee function (CHIEF) study.

Acute respiratory illnesses (ARI), comprising influenza-like illness (ILI) and other wintertime respiratory illnesses (ORI), impose substantial health and economic burdens on the United States. Little is known about the impact of ILI among household members (HHM), particularly children, on employees' productivity. To quantify the impact of employee and HHM-ILI and ARI on employee productivity, a prospective, observational cohort study was conducted among employees from three large US companies. Employees who had at least one child living at home (N=2013) completed a monthly survey during the 2007-2008 influenza season, reporting the number of days missed from work and hours of presenteeism due to: (1) personal ILI, (2) HHM-ILI, and (3) personal and HHM-ARI. Employee ILI ranged from 4.8% (April) to 13.5% (February). Employees reporting ILI reported more absences than employees not reporting ILI (72% vs 30%, respectively; P<0.001). Overall, 61.2% of employees surveyed had at least one child with an ILI; these employees missed more days of work due to HHM illness than employees without an ARI-ill child (0.9 days vs 0.3 days, respectively; P<0.001). Employees with ILI were less productive, on average, for 4.8h each day that they worked while sick, 2.5h of which was attributable to ILI. HHM illnesses accounted for 17.7% (1389/7868 days) of employee absenteeism, over half of which was due to HHM-ARI. ILI causes a significant amount of employee absence. Household members, particularly children, comprise a sizable proportion of general illness and injury-related employee absences.

Workshop on immunizations in older adults: identifying future research agendas.

Goals for immunization in older adults may differ from those in young adults and children, in whom complete prevention of disease is the objective. Often, reduced hospitalization and death but also averting exacerbation of underlying chronic illness, functional decline, and frailty are important goals in the older age group. Because of the effect of age on dendritic cell function, T cell-mediated immune suppression, reduced proliferative capacity of T cells, and other immune responses, the efficacy of vaccines often wanes with advanced age. This article summarizes the discussion and proceedings of a workshop organized by the Association of Specialty Professors, the Infectious Diseases Society of America, the American Geriatrics Society, the National Institute on Aging, and the National Institute of Allergy and Infectious Diseases. Leading researchers and clinicians in the fields of immunology, epidemiology, infectious diseases, geriatrics, and gerontology reviewed the current status of vaccines in older adults, identified knowledge gaps, and suggest priority areas for future research. The goal of the workshop was to identify what is known about immunizations (efficacy, effect, and current schedule) in older adults and to recommend priorities for future research. Investigation in the areas identified has the potential to enhance understanding of the immune process in aging individuals, inform vaccine development, and lead to more-effective strategies to reduce the risk of vaccine-preventable illness in older adults.

Modeling seasonal influenza outbreak in a closed college campus: impact of pre-season vaccination, in-season vaccination and holidays/breaks.

BACKGROUND: College and university students experience substantial morbidity from influenza and influenza-like illness, and they can benefit substantially from vaccination. Public health authorities encourage vaccination not only before the influenza season but also into and even throughout the influenza season. We conducted the present study to assess the impact of various vaccination strategies including delayed (i.e., in-season) vaccination on influenza outbreaks on a college campus. METHODS/FINDINGS: We used a Susceptible --> Infected --> Recovered (SIR) framework for our mathematical models to simulate influenza epidemics in a closed, college campus. We included both students and faculty/staff in the model and derived values for the model parameters from the published literature. The values for key model parameters were varied to assess the impact on the outbreak of various pre-season and delayed vaccination rates; one-way sensitivity analyses were conducted to test the sensitivity of the model outputs to changes in selected parameter values. In the base case, with a pre-season vaccination rate of 20%, no delayed vaccination, and 1 student index case, the total attack rate (total percent infected, TAR) was 45%. With higher pre-season vaccination rates TARs were lower. Even if vaccinations were given 30 days after outbreak onset, TARs were still lower than the TAR of 69% in the absence of vaccination. Varying the proportions of vaccinations given pre-season versus delayed until after the onset of the outbreak gave intermediate TAR values. Base case outputs were sensitive to changes in infectious contact rates and infectious periods and a holiday/break schedule. CONCLUSION: Delayed vaccination and holidays/breaks can be important adjunctive measures to complement traditional pre-season influenza vaccination for controlling and preventing influenza in a closed college campus.

Benefits and risks of live attenuated influenza vaccine in young children.

OBJECTIVE: To examine the benefit-risk profile of live attenuated influenza vaccine (LAIV) across a range of clinical scenarios in which we varied assumptions regarding both the percentage of children who would receive LAIV in lieu of trivalent inactivated influenza virus (TIV) and the extent of off-label use. STUDY DESIGN: Model of expected benefits and risks of immunization of young children against influenza. METHODS: We estimated expected numbers of cases of influenza illness (FLU), medically significant wheezing (MSW), and hospitalization in a single influenza season under alternative assumptions regarding use of LAIV in lieu of TIV, based on projections from a large phase III trial. RESULTS: Assuming no use of LAIV in nonindicated children (aged <24 months and those with history of recurrent wheezing or asthma), and 50% use in lieu of TIV among children in the indicated population, there would be 2099 fewer FLU cases per 100,000 children aged 12 to 59 months, and no change in MSW or hospitalization. If LAIV also were used in lieu of TIV among 20% of children aged 12 to 23 months and 20% of children aged 24 to 59 months with a history of recurrent wheezing or asthma, there would be a further reduction of 397 FLU cases and 12 hospitalizations per 100,000 children aged 12 to 59 months, but 51 additional MSW cases. CONCLUSIONS: Our study suggests that even if LAIV were sometimes used inadvertently in clinical practice in young children for whom it is not indicated, the overall balance of expected benefits and risks would remain favorable.