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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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Background. Uncertainties regarding influenza disease impact and benefits of vaccination may contribute to low vaccination rates among adults aged 50-64 years. Methods. This prospective cohort study assessed the burden of influenza-like illness (ILI) among working adults aged 50-64 years and the effectiveness of influenza vaccination in reducing the rate of ILI and productivity losses. Employees of the University of Minnesota (Minneapolis) were invited via e-mail to participate in the study during October 2006. The study data were collected using internet-based surveys at baseline (October 2006) and during the follow-up period (from November 2006 through April 2007). Months included in the 2006-2007 influenza season were identified retrospectively from Minnesota Department of Health surveillance data. Vaccine effectiveness for reducing the rate of ILI, ILI-associated health care use, the number of days of illness, work loss, and reduced on-the-job productivity during the influenza season were assessed using multivariable regression models after controlling for important confounders. Results. Four hundred ninety-seven persons were included in the study, 85 (17.1%) of whom experienced an ILI. Among unvaccinated participants, ILI was responsible for 45% of all days of illness during the influenza season, 39% of all illness-related work days lost, and 49% of all days with illness-related reduced on-the-job productivity. In the multivariable regression analyses, vaccination was associated with a significant reduction in the rate of ILI (adjusted odds ratio, 0.48; 95% confidence interval, 0.27-0.86) and fewer days of illness, absenteeism, and impaired on-the-job performance. Conclusion. ILIs were common among our study participants, accounting for a large portion of illness, work loss, and impaired work performance during the influenza season. Vaccination was associated with substantial health and productivity benefits. Vaccine delivery should be improved for this high-priority group. [ABSTRACT FROM AUTHOR]

Seasonal influenza continues to have a huge annual impact in the United States, accounting for tens of millions of illnesses, hundreds of thousands of excess hospitalizations, and tens of thousands of excess deaths. Vaccination remains the mainstay for the prevention of influenza. In the United States, 2 types of influenza vaccine are currently licensed: trivalent inactivated influenza vaccine and live attenuated influenza vaccine. Both are safe and effective in the populations for which they are approved for use. Children, adults <65 years of age, and the elderly all receive substantial health benefits from vaccination. In addition, vaccination appears to be cost-effective, if not cost saving, across the age spectrum. Despite long-standing recommendations for the routine vaccination of persons in high-priority groups, US vaccination rates remain too low across all age groups. Important issues to be addressed include improving vaccine delivery to current and expanded target groups, ensuring timely availability of adequate vaccine supply, and development of even more effective vaccines. Development of a vaccine against potentially pandemic strains is an essential part of the strategy to control and prevent a pandemic outbreak. The use of existing technologies for influenza vaccine production would be the most straightforward approach, because these technologies are commercially available and licensing would be relatively simple. Approaches currently being tested include subvirion inactivated vaccines and cold-adapted, live attenuated vaccines. Preliminary results have suggested that, for some pandemic antigens, particularly H5, subvirion inactivated vaccines are poorly immunogenic, for reasons that are not clear. Data from evaluation of live pandemic vaccines are pending. Second-generation approaches designed to provide improved immune responses at lower doses have focused on adjuvants such as alum and MF59, which are currently licensed for influenza or other vaccines. Additional experimental approaches are required to achieve the ultimate goal for seasonal and pandemic influenza prevention—namely, the ability to generate broadly cross-reactive and durable protection in humans. [ABSTRACT FROM AUTHOR]

Influenza causes substantial morbidity across the age spectrum. However, the elderly are especially vulnerable to the serious complications of influenza that might result in hospitalisation or death, and high rates of influenza-associated excess hospitalisation or death that exceed by several-fold the rates seen among most other age groups have consistently been observed in many countries and across many seasons. Thus, the elderly are included among the high priority groups for routine influenza vaccination by many national health authorities. Inactivated influenza virus vaccines are widely available across the globe and are safe and effective. Vaccination of elderly persons has been associated with significant reductions in hospitalisations for pneumonia and influenza as well as hospitalisations for other cardiopulmonary disorders and even cerebrovascular disease. Vaccination has also been associated with reductions in influenza-associated and all-cause mortality during influenza seasons. The benefits of vaccination extend not only to community-dwelling elderly but also to elderly who reside in nursing homes. Likewise, vaccination provides benefits to the very old and to elderly persons with underlying co-morbidities as well as to the healthy elderly. Despite the substantially increased risk for serious complications and impressive benefits from vaccination among the elderly, influenza vaccine utilisation remains below target rates for this group in nearly all countries. The need for improved prevention and control of influenza is recognised as a priority for the global community – both to reduce the morbidity and mortality associated with epidemic influenza and to prepare for the next pandemic. Enhancing vaccine delivery to elderly persons would represent important progress toward that goal. [ABSTRACT FROM AUTHOR]

Objective: To describe current immunization requirements and policies in North American medical schools both at matriculation and before students begin clinical clerkships.Design: Survey of all allopathic medical schools in the United States and Canada.Participants: One hundred and fifteen medical schools.Measurements and Main Results: Twenty-eight percent of medical schools had no immunization requirements for matriculating medical students. Thirty-one percent of the schools had no rubella immunity requirement, 40% had no measles immunity requirement, and 44% had no polio immunity requirement for matriculating students. For students beginning clinical clerkships, 18%, 35%, and 40% of schools did not require rubella, measles, and polio immunity, respectively. Only 19% and 4% of schools required hepatitis B and influenza immunizations, respectively, at any time during training. Between 20% and 30% of schools accepted student self-report as evidence of rubella and measles immunity.Conclusions: Despite expert guidelines, current medical school immunization policies for matriculating medical students are inadequate. Methods to assess, monitor compliance with, and facilitate student immunization are needed. Medical schools should review their immunization policies to comply with published guidelines. [ABSTRACT FROM AUTHOR]

Questions have been raised regarding the apparent lower than expected impact on excess mortality rates of increasing influenza vaccination rates among elderly persons in the United States. One possible explanation might be that influenza vaccine is less effective among elderly persons. To explore whether age is independently associated with influenza vaccine effectiveness, we used computerized administrative and clinical data to study >120,000 elderly members from three large managed care organizations in the United States over each of four influenza seasons, 1996–1997 through 1999–2000. After multivariable logistic regression to control for covariates and potential confounders, influenza vaccine effectiveness was similar among persons ≥85 years when compared with persons 65–74 years of age. However, persons ≥85 years were more likely to have medical comorbidities and a higher risk of dying. Unvaccinated persons ≥85 years with underlying chronic medical conditions were nearly 25 times more likely to die than were healthy, vaccinated persons 65–74 years of age. The impact of an aging population that also develops more chronic medical conditions on the absolute numbers of excess deaths due to influenza should be taken into account when attempting to evaluate the population level impact of increasing vaccination rates. Our data suggest that influenza vaccines themselves are otherwise similarly effective among the very old as among younger elderly persons after taking into account both age and underlying burden of illness. [Copyright &y& Elsevier]

Presents a reply on an article concerning the immune function and vaccine responses in healthy elderly persons. Function of B-celll in the characterization of the ability of elderlies to produce antibodies in response to immunization; Effectiveness of vaccines to elderlies; Complexities in separating the immunologic perturbations ascribed to aging.

Editorial. Offers observations on the revaccination of elderly adults against pneumonia. Reference to study by Shapiro et al which found decreasing estimates of protection with increasing intervals after vaccination among the elderly; Study by Jackson et al in the same issue which offers new information regarding the frequency of adverse effects following pneumococcal revaccination.

Abstract: Our aim was to provide a better understanding of why many adults fail to receive recommended immunizations. Consumers (N = 2,002) and healthcare providers (N = 200) completed structured telephone interviews concerning their attitudes and knowledge about adult vaccines and factors affecting their vaccination decisions. Self-reported immunization rates for tetanus, influenza, and pneumococcal vaccines (which were emphasized in the surveys) were lower than goal rates set by national guidelines. Among the most common reasons consumers gave for not receiving immunizations were lack of physician recommendations and mistaken assumptions (e.g., healthy people do not need immunizations). Healthcare providers tended to cite concerns such as side effects, fear of needles, and lack of insurance coverage as reasons consumers forego vaccination. Providers also cited practice issues, such as lack of an effective reminder system, as barriers to increasing adult immunization rates. We conclude that a better understanding of why adults do not get vaccinated is important for efforts to increase immunization rates in this broad age group. [Copyright &y& Elsevier]

Abstract: Nontraditional settings (NTS) are increasingly utilized for adult vaccination but concerns exist about their safety. We conducted this analysis of 542,445 persons vaccinated at an NTS in Minnesota to assess the safety of influenza vaccination in NTS. A total of 112 adverse events (AEs) were reported, 95 immediate and 17 late. Most AEs were mild and resolved within several minutes. 63 persons (.01%) had a vasovagal reaction to vaccination and 22 (.004%) reported an injection site problem. Immediate hypersensitivity reactions were very rare with only 10 (.002%) vaccine recipients having an immediate reaction for which epinephrine was required. Fifteen (.003%) individuals required evaluation in an emergency room or physician''s office because of an AE. No deaths were reported. We conclude that influenza vaccine administration in mass vaccination clinics is safe and adverse events after influenza vaccination in NTS are extremely low. [Copyright &y& Elsevier]