David S. Fedson

Influenza Vaccination in 29 Countries An Update to 1997

AbstractObjective: This report updates for 1996 and 1997 our 2 earlier reports on the use of influenza vaccination in various countries. Methods: Methods for obtaining information on influenza vaccine use from 1980 to 1995 in each country are described in our earlier reports. The current report includes data for 29 countries. Results: Among 16 countries of Western Europe, vaccine use increased substantially in The Netherlands, Finland (1996) and in Ireland (1997). In the remaining 13 countries, vaccine use increased somewhat or remained the same. In the US, vaccine use increased steadily throughout the 1990s, reaching a level of 281 doses per 1000 population in 1997. In New Zealand, there was a substantial increase in 1997, while vaccine use remained relatively unchanged in Canada, Australia and Korea. In Japan and Singapore, little or no influenza vaccine was used. In 1997, 6 countries in Central Europe used modest amounts of influenza vaccine. Among all 29 countries, in 1997 all but 3 (the UK, Ireland and Denmark) had age-based recommendations for influenza vaccination. This changed in 1998 when the UK and Denmark recommended vaccination for persons ≥75 years and ≥65 years of age, respectively. Ireland is considering an age-based recommendation. Many countries provide reimbursement for influenza vaccination through national or social health insurance, at least for some recommended groups. In virtually all countries, however, many persons pay for vaccination themselves. The levels of vaccine use in different countries are not related to per capita healthcare spending. Instead, they reflect different levels of awareness of influenza as an important disease and the effectiveness of vaccination in its prevention. Conclusions: Influenza vaccination has continued to increase or has stabilised in most developed countries, and vaccine is also being used in several developing countries. In spite of much progress, however, the full benefits of influenza vaccination have yet to be achieved in any country.

Improving the use of pneumococcal vaccine through a strategy of hospital-based immunization: a review of its rationale and implications.

Serious pneumococcal infections continue to be a major cause of morbidity and mortality in the United States. This is especially true for pneumococcal pneumonia. For example, in 1977 there were more than 58,000 deaths reported with pneumonia and influenza listed as the underlying cause. However, when all diagnoses mentioned on death certificates were examined, the number of pneumonia and influenza deaths approached 200,000.2 An unknown proportion of these deaths, at least several tens of thousands each year, are caused by pneumococcal pneumonia. Pneumococcal infections are still regarded as the major cause of community-acquired pneumonia requiring hospitalization, accounting for 26 to 76 per cent of cases in published seriess3s4 Bacteremic pneumococcal pneumonia continues to exact a high toll in mortality. In earlier series reported from 1964 to 1978 overall case-fatality rates ranged from 10 to 35 per cent.3 Recent studies have shown that this is unchanged; seven reports published since 1982 document overall mortality rates ranging from 13 to 31 percent (Table l).5-11 In these studies, elderly persons (aged 60 or 65 years and older) have accounted for 23 to 49 per cent of cases, and fhtality rates have ranged from 17 to 40 per cent. The economic costs of pneumococcal pneumonia have also been substantial; with hospital care accounting for 90 per cent of the medical care costs in persons of all ages, and 97 per cent of these costs among the elderly. l2 In 1977, a first generation 14-valent pneumococcal polysaccharide vaccine appeared in the United States. Licensure was based on the vaccine’s demonstrated antigenicity, freedom from serious adverse reactions, and efficacy in preventing serious pneumococcal infections as shown in randomized controlled trials in young adults. In its

Disparity between Influenza Vaccination Rates and Risks for Influenza-associated Hospital Discharge and Death in Manitoba in 1982-1983

OBJECTIVE To determine, in a defined population, the percentage of persons who were discharged from a hospital or died of influenza-associated respiratory conditions who had a health care contact during the preceding vaccination season and to determine the relation between risk status for influenza-associated hospitalization and death and influenza vaccination rates. DESIGN An observational study using linked-record analysis of medical claims data. SETTING AND PATIENTS A probability sample of 100,000 noninstitutionalized adults living in Manitoba in 1982 to 1983. MEASUREMENTS Analysis of medical claims for influenza vaccination and hospital discharges and deaths for influenza-associated respiratory conditions during the 1982-83 influenza vaccination season and influenza outbreak period. RESULTS For the population as a whole, 50% to 60% of elderly persons (greater than or equal to 65 years of age) and 30% to 40% of younger persons had one or more health care contacts during the influenza vaccination season but fewer than 10% of all persons had been discharged from a hospital. In contrast, for elderly persons hospitalized with respiratory conditions during the influenza outbreak period, approximately 80% had at least one health care contact during the vaccination season. Among the elderly, 39% to 46% of all those discharged for influenza-associated respiratory conditions and 62% to 67% of those who died had been discharged from hospital during the previous vaccination season. Persons discharged with high-risk conditions during the vaccination season were at greater risk for hospitalization with influenza-associated respiratory conditions but were less likely to be vaccinated than were those at lower risk. CONCLUSIONS Most persons who were hospitalized with influenza-associated respiratory conditions had contact with health care providers during the preceding influenza vaccination season. Among elderly patients, previous hospital care was common, especially among those who died. The disparity between influenza vaccination rates and risks for influenza-associated hospital discharge and death supports a strategy of hospital-based influenza vaccination.

Influenza prevention and control: Past practices and future prospects

Abstract The Immunization Practices Advisory Committee (ACIP) recommends annual influenza vaccination for elderly and high-risk persons [1]. This policy reflects continued recognition of influenza as an important cause of serious morbidity and excess mortality. Despite advances in medical care, there is little evidence to suggest that the impact of influenza is declining [2]. On the contrary, because the number of elderly persons is increasing, influenza appears destined to remain a significant health problem. The traditional approach to the prevention and control of influenza has focused on influenza vaccine, and particularly on its use by office-based physicians. It is widely acknowledged, however, that current immunization efforts are inadequate and that newer approaches to vaccine delivery are required. This report begins with a historical review of the use of influenza vaccine in the United States. Next, three methods of improving immunization practice are discussed. Finally, future prospects for improving influenza immunization are presented.

Acceptance of hepatitis B vaccine by medical and surgical residents

To assess factors influencing acceptance of hepatitis B vaccine, 547 medical residents and 230 surgical residents were surveyed. The vaccination rate among 315 (58%) medical residents who responded was 46%; for 124 (54%) surgical residents who responded it was 76%. Most medical (93%) and surgical (94%) residents who were vaccinated believed they were at risk of hepatitis B virus infection. Among unvaccinated medical residents, 71% indicated concern about vaccine-related side effects, including potential but unknown reactions (58%) and possible transmission of AIDS (37%) and hepatitis (16%). Unvaccinated surgical residents were also concerned about side effects (64%). Stepwise discriminant function analysis revealed that medical residents were vaccinated if they were concerned about risk of exposure to hepatitis B virus and the chronic complications of infection and if they had received hepatitis B immune globulin and influenza vaccine. Surgical residents were vaccinated if they believed hepatitis B vaccine was efficacious, but were not vaccinated if they believed hepatitis B virus infection was not serious.

Evaluating the impact of influenza vaccination. A North American perspective.

SummaryRecent studies in the US and Canada have shown that influenza vaccination prevents approximately 30 to 50% of all pneumonia and influenza hospitalisations and deaths that occur among elderly persons during 3-month influenza outbreak periods. These population-based studies have used retrospective methods and large computerised administrative databases. In addition, earlier cost-effectiveness studies have been supplemented by recent research from prepaid health plans showing that influenza vaccination can be cost saving.The use of influenza vaccine increased in the US and Canada throughout the 1980s and early 1990s, despite different methods for providing reimbursement for vaccination. The North American experience regarding the clinical effectiveness, cost effectiveness and epidemiology of influenza vaccination may provide European scientists and health officials with useful although sometimes limited insight into their own efforts to understand and improve influenza vaccination.

The Influenza Vaccination Demonstration Project: An Expanded Policy Goal

In 1980, the Public Health Service established an objective of immunizing 60% of high-risk persons with influenza vaccine annually by the year 1990. As no more than 32% of high-risk persons currently receive influenza vaccine each year, the Health Care Financing Administration (HCFA) has undertaken an influenza vaccination demonstration project for Medicare enrollees. Federally purchased vaccine is being distributed to physicians, health departments, hospitals, nursing homes and health maintenance organizations (HMOs). If the project is cost-effective, Congress has authorized HCFA reimbursement for influenza vaccination. Changing reimbursement policy alone, however, is unlikely to substantially improve influenza vaccine delivery; HCFA reimbursement for pneumococcal immunization since 1981 has not increased the use of pneumococcal vaccine. In contrast, federal purchase and distribution of vaccines to state and local health departments has helped maintain the remarkable success of childhood immunization programs. In addition, in Canada, provincial health departments purchase more than 80% of all influenza vaccine distributed, and from 1980 through 1988, per capita vaccine distribution increased 140%. These experiences suggest the need for an expanded policy goal for the influenza vaccination demonstration project that includes federal purchase and distribution of influenza vaccine. This approach, together with a change in reimbursement policy, offers greater promise for achieving our nations objective for influenza vaccination.

Restoring Balance to Internal Medicine Training: The Case for the Teaching Office Practice

Medical residents require an experience beyond the tertiary care hospital to understand many aspects of contemporary medical practice and to make informed career choices. To provide this balanced training, the University of Virginia has operated for 10 years an internal medicine teaching office practice to provide an outpatient experience similar to private practice. It allows residents to work closely with general internal medicine faculty and introduces them to the knowledge and skills necessary to establish and manage a successful practice. The curriculum of the 10 week rotation includes patient care in the office and by telephone, nursing home and home visits, tutorials and seminars on primary care and office management topics, and training in the use of microcomputers. A survey of 46 (92%) of the first 50 residents completing the rotation revealed that the content of the rotation was valuable, the rotation substantially influenced career choices, and the rotation helped provide a balanced view of internal medicine practice.

Reminding and monitoring: new uses of administrative data for preventive care.

This article illustrates how administrative data can be used to improve population health in an environment of fiscal constraint. In our universal single-payer health system, health care providers submit standardized data. This allows provinces to create health information utilities that generate population-based data that can be used for research and health care delivery. Although more study is needed to determine the cost-effectiveness of using such data to raise the rates of primary and secondary prevention, it appears that appropriately designed information systems could improve population health with relatively little additional cost.

Workshop. 3: Antivirals and vaccination for influenza.

Antivirals will not replace vaccination for recommended target groups in the future. Antivirals, and the new antivirals in particular, should be considered as an additional opportunity for the prevention and control of influenza and not as a threat to our traditional use of vaccines. The history of amantadine and rimantadine during the last 20 years is largely one of neglect, but this will not necessarily be repeated in future years with the antineuraminidase inhibitors. Indeed, there may even be a rebirth in the use of these older agents, particularly of rimantadine. In the elderly and in other high risk individuals, vaccination will clearly remain the foundation of prevention. However, in vaccinated individuals who develop influenza virus infections, supplementary treatment with antiviral agents is warranted. Clinical studies may eventually show that combination antiviral treatment with rimantadine and neuraminidase inhibitors should be considered in these groups. Antivirals can be used as prophylaxis for those who are unvaccinated. Prophylaxis and/or treatment with antivirals in unvaccinated individuals and in vaccinated persons during influenza outbreaks are also clearly worth pursuing. An important study of influenza vaccination and/or amantadine prophylaxis and treatment in the nursing home setting found that, when confronted with an outbreak, the use of both vaccination and amantadine was far and away the best choice. The treatment of severe influenza complications in hospitalised patients attracts a great deal of attention, and is probably the one area where antiviral agents will be most intensively studied and their value most specifically realised. As vaccines are imperfect agents, studies specifically examining antiviral treatment in individuals who have been vaccinated and who nonetheless develop influenza will also be useful. In addition, the occasional mismatch of influenza vaccine viruses and naturally occurring strains will reduce the effectiveness of vaccination and create a niche for the antivirals. There is only one group of patients for whom antiviral agents alone, not vaccine, must be relied on to prevent or control influenza, and that is patients who are immunocompromised and will not respond to vaccination. In this group, combination antiviral treatment may be especially important.