The cost-effectiveness of influenza vaccination of healthy adults 50-64 years of age. Vaccine, 24(7), 1035-1043
Influenza can cause significant morbidity and mortality. Influenza vaccination is an effective and safe strategy in the prevention of influenza. Currently the National Health Service (NHS) vaccinates 'at-risk' individuals only. This definition includes everyone over 65 years of age but excludes individuals 50-64 years of age unless they have an additional risk factor, such as underlying heart disease or lung disease. In order to examine the cost-effectiveness of an extension of the vaccination policy to include this age group we constructed an economic model to estimate the costs and benefits of vaccination from both a health service and a societal perspective. Data to populate the model was obtained from the literature and the outcome measure used was the quality adjusted life year (QALY). Influenza vaccination prevented an estimated 4508 cases (95% CI: 2431-7606) per 100,000 vaccinees per influenza season for a net cost to the NHS of pound653,221 (95% CI: 354,575-1,072,257). The net cost increased to pound1,139,069 (95% CI 27,052-2,030,473) when non-NHS costs were included and the estimated cost-per-QALY were pound6174 and pound10,766 for NHS and all costs respectively. Extension of the current immunisation policy has the potential to generate a significant health benefit at a comparatively low cost.
[Show abstract] [Hide abstract] ABSTRACT: The supplementary text provides further detailed information pertaining to the modelling of disease dynamics and vaccination behavior, the classification of a superspreader and the various vaccination strategies. (PDF)0Comments 0Citations
- "where γ is the probability of a vaccine complication occurring. The value of c inf was based upon utility penalties constructed from patient surveys . The value of c vac was based on published vaccine costs and held fixed for the calibration of the vaccine coverage. "
[Show abstract] [Hide abstract] ABSTRACT: Theoretical models of infection spread on networks predict that targeting vaccination at individuals with a very large number of contacts (superspreaders) can reduce infection incidence by a significant margin. These models generally assume that superspreaders will always agree to be vaccinated. Hence, they cannot capture unintended consequences such as policy resistance, where the behavioral response induced by a new vaccine policy tends to reduce the expected benefits of the policy. Here, we couple a model of influenza transmission on an empirically-based contact network with a psychologically structured model of influenza vaccinating behavior, where individual vaccinating decisions depend on social learning and past experiences of perceived infections, vaccine complications and vaccine failures. We find that policy resistance almost completely undermines the effectiveness of superspreader strategies: the most commonly explored approaches that target a randomly chosen neighbor of an individual, or that preferentially choose neighbors with many contacts, provide at best a [Formula: see text] relative improvement over their non-targeted counterpart as compared to [Formula: see text] when behavioral feedbacks are ignored. Increased vaccine coverage in super spreaders is offset by decreased coverage in non-superspreaders, and superspreaders also have a higher rate of perceived vaccine failures on account of being infected more often. Including incentives for vaccination provides modest improvements in outcomes. We conclude that the design of influenza vaccine strategies involving widespread incentive use and/or targeting of superspreaders should account for policy resistance, and mitigate it whenever possible.0Comments 4Citations
- "For each of the ten networks, the transmission probability and amplitude of seasonality were calibrated so that the average seasonal incidence of influenza in the absence of vaccination was 15%404142, and prevalence peaked between January and February. c inf was based upon utility scores derived from patient surveys . c vac was based on published vaccine costs [41,444546. "
[Show abstract] [Hide abstract] ABSTRACT: The seasonal influenza vaccination programme in England targets individuals over 65 years old and in clinical risk groups. A model of influenza transmission and disease was fitted to weekly primary care consultations due to influenza in a typical pre-pandemic season (2006/2007). Different scenarios were constructed about influenza severity and how well vaccines match circulating strains to assess the impact and cost-effectiveness of the current vaccination programme. A well-matched vaccine may reduce the incidence of laboratory-confirmed influenza illness from 8.2% (95% range 4.3-13%) to 5.9% (95% range 2.9-9.7%), with 56-73% of this due to indirect protection. The programme is likely to be cost-effective unless both low severity and poor matching is assumed. The current seasonal influenza vaccination programme appears to substantially reduce disease burden and provides good value for money.0Comments 27Citations
- "The impact and economic rationale of country-specific recommendations is not always well established, and indeed was recently debated in the United Kingdom. Some economic models have examined the impact of extending recommendations to other groups such as children under 12 years or adults 50–64 years  . However, most of these are static models that do not realistically model infection transmission, and hence indirect protection in non-vaccinated individuals such as Abbreviations: GP, general practitioner; GPRD, General Practice Research Database; ILI, influenza-like illness; QALY, quality-adjusted life year; RCGP, Royal College of General Practitioners. "