Influenza deaths in Leicestershire during the 1989–90 epidemic: implications for prevention

Abstract

SUMMARYThere is an association between excess winter mortality and epidemics of influenza and it has been suggested that annual influenza vaccination should be offered to all over 65 years old as in the United States. This paper identifies the number of people dying from influenza in Leicestershire UK during the 1989-90 epidemic and the factors associated with a fatal outcome. The findings show that deaths attributed to influenza occur predominantly in very elderly people with underlying ill-health. The risk of influenzal death is greater in residential patients and increases substantially with the number of underlying medical conditions. The estimated death rates in vaccinated and non-vaccinated groups were not significantly different, but there were trends towards protection in both residential and non-residential groups. Influenza vaccine is not reaching the principal target groups and improved methods of influenza control are required. Morbidity and mortality from influenza increase with age and presence of chronic disease [2] and the institutionalised elderly are thus placed at particular risk. The size of the elderly population in the United Kingdom is increasing and the number of those aged over 75 years is projected to increase by 358000 (9 9 %) during the next decade [3]. Influenza vaccine offers 60-80 % protection to healthy adults when vaccine and epidemic strains are closely related, but studies in elderly care homes reveal a mean protection of only 27 % against influenza-like illness for influenza A (H3N2) vaccines, and 21 % for influenza B vaccines [4]. Despite these

Fatores de risco e medidas profiláticas nas pneumonias adquiridas na comunidade

“…Além do grau de similaridade entre as cepas dos vírus contidos na vacina e as cepas circulando na comunidade, o sucesso da vacina depende também da idade e do sistema imunológico do paciente. Embora a influenza acometa mais freqüentemente crianças e adolescentes, a taxa de morbidade e mortalidade é maior nos pacientes idosos, sendo o vírus da influenza A o responsável habitual pelas epidemias, pandemias e mortes neste grupo (49) . É questionável se a idade é um fator de risco independente.…”

“…É questionável se a idade é um fator de risco independente. Nguyen-Van-Tam e Nicholson (49) , revisando os prontuá-rios de pacientes que morreram por influenza durante a epidemia ocorrida na Inglaterra em 1989-1990 (influenza H3N2), mostraram que 93% deles apresentavam uma ou mais doenças crônicas subjacentes. Nichol et al (50) (51) .…”

Influenza immunization; vaccine offer, request and uptake in high-risk patients during the 1991/2 season

“…A further 9 (4-6 %) had accepted because they considered the vaccine was generally worthwhile and 10 (5-2 %) because they felt that they were at increased risk from influenza; 11 respondents (5-7 %) gave other reasons for acceptance such as media publicity, general practitioners' publicity, 'force of habit' and the offer of vaccine made in the workplace. DISCUSSION Whilst the groups studied do not represent the full range of patients with medical conditions for which vaccine is recommended [6], the increased risk of complications from influenza (including death) in patients with chronic cardiovascular and respiratory disease, and diabetes has been well documented [10,[15][16][17]. Moreover, of the chronic medical conditions for which vaccine is indicated, those studied are numerically important because of their high prevalence in the community [14], and the nature and severity of illness in our chosen subjects had brought them into regular contact with general practitioners (mean of 6-7 consultations in past 12 months) and hospital services (mean of 4 9 out patient visits in past 12 months).…”

“…In the influenza epidemic which followed in 1989/90, there were 29000 excess deaths in Great Britain, almost exclusively in elderly people [9]. In Leicestershire, UK during the epidemic, the influenza immunization rate in those that died from certified influenza was 24 % (10 of 42), but 93 % (39 of 42) had indications for the vaccine [10]; death rates from certified influenza were related to the number of underlying chronic illnesses suffered by individuals prior to their final illness, ranging from 6-6 deaths/100000 in elderly people living at home and free from chronic illness, to 2703 deaths/100000 among elderly residents of nursing and old people's homes with three or more chronic illnesses [10]. During the same epidemic the immunization rate among asthmatic individuals in Leicestershire was 15% [11].…”

“…During the same epidemic the immunization rate among asthmatic individuals in Leicestershire was 15% [11]. Although these vaccine studies were confined to the Trent health region, UK they suggest that large deficiencies exist in the delivery of vaccine to high risk groups [7][8][9][10][11]. A survey of general practices conducted in England during 1992 revealed that 89% had an agreed policy for influenza immunization [12]; this represents a significant increase over the 69 % reported in 1986 [8].…”