■Une utilisation variable selon les pays: Le premier enregistrement du vaccin pneumococcique dat... more ■Une utilisation variable selon les pays: Le premier enregistrement du vaccin pneumococcique date de 1977. Son utilisation a d'abord ete limitee aux Etats-Unis d'Amerique pendant les annees 80. Huit autres pays ont commence a utiliser le vaccin pneumococcique dans les annees 90: l'Islande (1991); le Royaume-Uni (1994); la Suede (1995); la Belgique, la Norvege et le Canada (1996); l'Australie et le Danemark (1997). A l'exception de la Suede, la vaccination pneumococcique croit dans chacun de ces pays. En France, la vaccination pneumococcique continue a etre peu utilisee. ■Les conditions de l'utilisation: Les caracteristiques specifiquement liees au succes de la vaccination pneumococcique dans ces 9 pays sont identiques a celles de la vaccination grippale, a savoir, la recommandation de la vaccination en fonction de l'âge et le remboursement. Pour cette raison, il est probable que la vaccination pneumococcique ne sera largement pratiquee en France que lorsqu'elle sera recommandee chez les personnes âgees et remboursee.
Serious pneumococcal infections continue to be a major cause of morbidity and mortality in the Un... more 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
In the clinical development of a vaccine, an efficacy study asks the question, "Does the vac... more In the clinical development of a vaccine, an efficacy study asks the question, "Does the vaccine work?" In contrast, an effectiveness study asks the question "Does vaccination help people?". In general, vaccine development proceeds from a study of immunogenicity to a randomized controlled trial that determines vaccine efficacy under ideal conditions. Efficacy studies, however, have several limitations. In an immunogenicity study, when a vaccine is given according to different schedules, the object of the study is not the vaccine itself but the schedules; i.e., what is important is not the "relative immunogenicity" of the vaccine, but which schedule is more protective given the occurrence of the disease that is to be prevented. Furthermore, a clinical trial of vaccine efficacy is unable to predict accurately the level of protection that will be achieved in public health practice. Vaccination effectiveness can be evaluated in a prospective clinical trial,...
Recent studies have shown that there are approximately 40,000 to 45,000 cases of invasive pneumoc... more Recent studies have shown that there are approximately 40,000 to 45,000 cases of invasive pneumococcal disease and 480,000 to 800,000 hospital discharges for pneumococcal pneumonia (all-listed diagnoses) in the United States each year. The impact of pneumococcal disease is especially severe among older persons > or = 65 years in age. Case-control studies and indirect cohort studies have shown that pneumococcal vaccination is effective in preventing invasive pneumococcal disease in older, high-risk patients. The Office of Technology Assessment has shown that pneumococcal vaccination would be cost-effective in preventing pneumococcal pneumonia in the elderly. However, in the absence of data on the clinical effectiveness of vaccination in preventing pneumococcal pneumonia, physicians have been reluctant to vaccinate their patients, and only 20% of older persons have ever been immunized. Yet it is not necessary to know whether the vaccine is clinically effective or cost-effective in ...
This study compares influenza and pneumococcal vaccination in Canada and the United States during... more This study compares influenza and pneumococcal vaccination in Canada and the United States during the period 1980-1993. In Canada, the annual distribution of influenza vaccine during this period increased from 33 to 146 doses per 1,000 population. Provincial health departments purchased 80%-90% of all doses distributed. In the United States, annual distribution of influenza vaccine ranged from 70 to 102 doses per 1,000 population from 1981 to 1990 but increased to 159 doses per 1,000 population over the next 3 years. Throughout the study period, the distribution of pneumococcal vaccine in the United States greatly exceeded that in Canada. Despite similar recommendations regarding the use of these vaccines in the two countries, vaccination practices have differed. In Canada, success with influenza vaccination but not pneumococcal vaccination appears to reflect active public-sector involvement in programs for vaccine purchase and delivery. In the United States, the recent increase in the use of both influenza and pneumococcal vaccines has occurred in the absence of substantial public-sector involvement and may reflect the entrepreneurial nature of American medical practice.
■Une utilisation variable selon les pays: Le premier enregistrement du vaccin pneumococcique dat... more ■Une utilisation variable selon les pays: Le premier enregistrement du vaccin pneumococcique date de 1977. Son utilisation a d'abord ete limitee aux Etats-Unis d'Amerique pendant les annees 80. Huit autres pays ont commence a utiliser le vaccin pneumococcique dans les annees 90: l'Islande (1991); le Royaume-Uni (1994); la Suede (1995); la Belgique, la Norvege et le Canada (1996); l'Australie et le Danemark (1997). A l'exception de la Suede, la vaccination pneumococcique croit dans chacun de ces pays. En France, la vaccination pneumococcique continue a etre peu utilisee. ■Les conditions de l'utilisation: Les caracteristiques specifiquement liees au succes de la vaccination pneumococcique dans ces 9 pays sont identiques a celles de la vaccination grippale, a savoir, la recommandation de la vaccination en fonction de l'âge et le remboursement. Pour cette raison, il est probable que la vaccination pneumococcique ne sera largement pratiquee en France que lorsqu'elle sera recommandee chez les personnes âgees et remboursee.
Serious pneumococcal infections continue to be a major cause of morbidity and mortality in the Un... more 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
In the clinical development of a vaccine, an efficacy study asks the question, "Does the vac... more In the clinical development of a vaccine, an efficacy study asks the question, "Does the vaccine work?" In contrast, an effectiveness study asks the question "Does vaccination help people?". In general, vaccine development proceeds from a study of immunogenicity to a randomized controlled trial that determines vaccine efficacy under ideal conditions. Efficacy studies, however, have several limitations. In an immunogenicity study, when a vaccine is given according to different schedules, the object of the study is not the vaccine itself but the schedules; i.e., what is important is not the "relative immunogenicity" of the vaccine, but which schedule is more protective given the occurrence of the disease that is to be prevented. Furthermore, a clinical trial of vaccine efficacy is unable to predict accurately the level of protection that will be achieved in public health practice. Vaccination effectiveness can be evaluated in a prospective clinical trial,...
Recent studies have shown that there are approximately 40,000 to 45,000 cases of invasive pneumoc... more Recent studies have shown that there are approximately 40,000 to 45,000 cases of invasive pneumococcal disease and 480,000 to 800,000 hospital discharges for pneumococcal pneumonia (all-listed diagnoses) in the United States each year. The impact of pneumococcal disease is especially severe among older persons > or = 65 years in age. Case-control studies and indirect cohort studies have shown that pneumococcal vaccination is effective in preventing invasive pneumococcal disease in older, high-risk patients. The Office of Technology Assessment has shown that pneumococcal vaccination would be cost-effective in preventing pneumococcal pneumonia in the elderly. However, in the absence of data on the clinical effectiveness of vaccination in preventing pneumococcal pneumonia, physicians have been reluctant to vaccinate their patients, and only 20% of older persons have ever been immunized. Yet it is not necessary to know whether the vaccine is clinically effective or cost-effective in ...
This study compares influenza and pneumococcal vaccination in Canada and the United States during... more This study compares influenza and pneumococcal vaccination in Canada and the United States during the period 1980-1993. In Canada, the annual distribution of influenza vaccine during this period increased from 33 to 146 doses per 1,000 population. Provincial health departments purchased 80%-90% of all doses distributed. In the United States, annual distribution of influenza vaccine ranged from 70 to 102 doses per 1,000 population from 1981 to 1990 but increased to 159 doses per 1,000 population over the next 3 years. Throughout the study period, the distribution of pneumococcal vaccine in the United States greatly exceeded that in Canada. Despite similar recommendations regarding the use of these vaccines in the two countries, vaccination practices have differed. In Canada, success with influenza vaccination but not pneumococcal vaccination appears to reflect active public-sector involvement in programs for vaccine purchase and delivery. In the United States, the recent increase in the use of both influenza and pneumococcal vaccines has occurred in the absence of substantial public-sector involvement and may reflect the entrepreneurial nature of American medical practice.
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