1,721,038 research outputs found
Cost-effectiveness analysis of pneumococcal conjugate vaccination in England and Wales
No full textTo establish whether universal vaccination of infants with the pneumococcal conjugate vaccine is likely to be cost-effective from the perspective of the health care provider (NHS).: Two hypothetical cohorts - one vaccinated and one unvaccinated - were followed over their lifetime, and the expected net costs and benefits (measured in terms of life-years and quality adjusted life years (QALY) gained) were compared in the two cohorts. The impact of indirect effects of the vaccine, such as herd immunity and serotype replacement, were investigated and their relative importance was assessed by performing univariate sensitivity analysis and multivariate Monte Carlo simulations.: Under base-case assumptions (no herd immunity and no serotype replacement) the programme is not expected to be cost-effective from the NHS perspective at the current price of the vaccine (assumed £30 per dose, three-dose programme). A reduction of the cost of the vaccine to half of its current level could bring the cost per QALY gained within normally acceptable ranges. If the burden of disease is significantly underestimated by current surveillance systems, then the cost per QALY gained approaches acceptable levels at the current vaccine price. Herd immunity may substantially reduce the burden of pneumococcal disease, particularly of pneumonia among the elderly, leading to a significant improvement in the cost per life year and QALY gained. Serotype replacement would partly offset these benefits, although only with a complete substitution of vaccine types with non-vaccine types and a low level of herd immunity, would pneumococcal vaccination programme would not be cost-effective.: Conclusions on the cost-effectiveness of pneumococcal conjugate vaccine are sensitive to assumptions regarding the current burden of pneumococcal disease and the future impact that vaccination will have in the unvaccinated and on the future serotype distribution. This study quantifies, for the first time, how these indirect effects may change the cost-effectiveness of pneumococcal vaccination. © 2004 Elsevier Ltd. All rights reserved
The DECIDE Project: The impact of DEmographic Changes on Infectious DisEases transmission and control in middle/low income countries.
No full textFirst International Meeting of International Biometric Society (IBS) Uganda: "Modeling Infectious Diseases in Uganda and Africa: Current Status and Future Challenges", Kampala, Uganda, September 2-4, 2013 [oral presentation
The 23-valent pneumococcal polysaccharide vaccine. Part I. Efficacy of PPV in the elderly: a comparison of meta-analyses.
No full textA 23-valent polysaccharide pneumococcal vaccine (PPV) has been available in the UK for more than 20 years and is currently recommended for use in high-risk groups (HRG) of 2+ years of age. The degree of protection afforded by the PPV remains a critical issue, although a number of randomised clinical trials and case-control studies (CCS) have been published. The aim of this work is to review the estimates on the efficacy of PPV against pneumococcal pneumonia and invasive pneumococcal disease (IPD) in the elderly and to perform a meta-analysis in order to obtain a pooled estimate of the level of protection in high and low risk individuals. These two groups of individuals are at the centre of the current debate on whether or not to extend the vaccination programme to all elderly individuals 65+. Only randomised and quasi-randomised studies are included in the analysis and results are compared with previous meta-analyses. The effect of the inclusion of observational studies is investigated in the sensitivity analysis. When taken with the results of other meta-analyses and observational studies, it appears that PPV offers protection against IPD in the general elderly population (VE = 65%; 95% CI: -49-92%) whereas it has a moderate effect in the high-risk elderly (VE = 20%; 95% CI: -188-78%). The vaccine has little or no effect against pneumonia (VE = 16% in the general elderly and -20% in HRG)
The 23-valent pneumococcal polysaccharide vaccine. Part II. A cost-effectiveness analysis for invasive disease in the elderly in England and Wales.
No full textThe 23-valent pneumococcal polysaccharide vaccine (PPV) has been available for a number of years and is recommended for high-risk categories. Relatively immunocompetent elderly people are not included in this group, although their probability of getting invasive pneumococcal infection is high. The objective of this study was to assess whether vaccinating all elderly people over 65 years of age was a cost-effective policy for England and Wales. The analysis was performed comparing the cost and health effects produced by vaccination, to what would have been occurred if vaccination were not introduced. A decision analysis model was used in order to predict health outcomes under different vaccination scenarios. Unit costs were applied to the outcome and the cost per life-year gained was calculated. Sensitivity analysis was performed to allow for uncertain parameters to vary. The current UK recommendation does not appear to be the most cost-effective strategy due to the low level of efficacy of the vaccine in high-risk groups (HRG) and their shorter life expectancy. Routine vaccination of all elderly appears to be more cost-effective. These results are, nevertheless, very much dependent on the uncertainties around vaccine efficacy estimates, which appear to be still present, especially in HRG, and on the number of hospitalisations and deaths attributable to invasive pneumococcal disease (IPD)
A longitudinal household study of Streptococcus pneumoniae nasopharyngeal carriage in a UK setting.
Get PDFA 10-month longitudinal household study of pre-school children and their families was undertaken with monthly visits collecting epidemiological data and nasopharyngeal swabs in Hertfordshire, England from 2001 to 2002. Pneumococcal culture was with standard methods. In total, 121 families (489 individuals) took part. Mean prevalence of carriage ranged from 52% for age groups 0-2 years, 45% for 3-4 years, 21% for 5-17 years and 8% for >or=18 years. Carriage occurred more than once in 86% of children aged 0-2 years compared to 36% of those aged >or=18 years. The most prevalent serotypes in the 0-2 years age group were 6B followed by 19F, 23F, 6A and 14. Young children were responsible for the majority of introductions of new serotypes into a household. Erythromycin resistance (alone or in combination) occurred in 10% of samples and penicillin non-susceptibility in 3.7%. Overall the recently licensed 7-valent conjugate vaccine (PCV) would protect against 64% of serotypes with no intra-serogroup cross protection and 82% with such protection. Nasopharyngeal carriage of S. pneumoniae is common in a UK setting in the pre-conjugate vaccine era. PCV would protect against a large proportion of carriage isolates. However, the impact of vaccination on non-vaccine serotypes will need to be monitored
The impact of DEmographic Changes on Infectious DisEases transmission and control in middle/low income countries (The DECIDE Project).
No full textAlpine Population Conference (AlpPop) 2013, La Thuile (AO), Italy, January 13-16, 2013 [poster
Estimating the transmission parameters of pneumococcal carriage in households
Get PDFThis paper analyses Streptococcus pneumoniae transmission dynamics in households using longitudinal data on pneumococcal (Pnc) carriage in the United Kingdom. Ten consecutive swabs were taken at 4-week intervals from all members of 121 households. The family status is derived from the observed Pnc carriage status of each family member. Transition matrices are built for each family size and composition containing the observed frequency of transitions between family statuses over a 28-day interval. A density-dependent transmission model is fitted to derive maximum-likelihood estimates of the duration of carriage and acquisition rates from the community and from infected individuals within the household. Parameter values are estimated for children (<5 years) and adults (5+years). The duration of carriage is longer in children <5 years of age than in older family members (51 vs. 19 days). Children are 3–4 times more likely than adults to acquire Pnc infection from the community. Transmission rates within the household suggest that adults are more infectious but less susceptible than children. Transmission within the household is most important in large families. The proportion of household-acquired infection ranges from 29 to 46% in households of three persons to 38–50% in larger households. Evidence of density-dependent within-household transmission is found, although the strength of this relationship is not clear from the model estimates
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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