Individuals at risk of influenza related complications include those with

chronic respiratory, heart, liver or kidney disease, and the immunosuppressed, as well as all individuals over the age of 64 years [10]. Although at risk individuals are ZD1839 in vivo currently targeted for seasonal vaccination in England and Wales and a number of other European countries, vaccination rates in most countries are suboptimal although coverage of the elderly is often better than that of clinical risk groups [11] and [12]. A recent survey has shown that vaccination rates in the elderly differ considerably across Europe [12], being highest in the UK (70.2%) and lowest in Eastern European countries such as Poland (13.9%). Furthermore, evidence is accumulating that vaccination of the elderly with an inactivated vaccine offers only partial protection. Reported estimates of vaccine effectiveness vary widely in the elderly, ranging from 20% to over 50% [13] and [14]. Vaccination rates in individuals with a chronic medical MLN8237 purchase condition considered at a high risk

of developing complications due to influenza are also low, ranging from 56% in the UK to 11% in Poland. Vaccination rates have increased marginally over the last few years. Non-vaccinated individuals constitute a hard to reach group. In those EU member states where vaccination rates are low due to the absence of funding, childhood vaccination may be an attractive option. Provided adequate coverage is achieved, not only will children be protected but herd immunity could offer protection to at risk groups across the age ranges. The aim of this paper is to estimate the

potential clinical impact of paediatric influenza vaccination in England and Wales. Specific objectives were to develop a demographic model of England and Wales, to capture the population structure over time, and to create a dynamic transmission model simulating the transmission of influenza and the current influenza vaccination policy. A set of risk functions were developed to translate the out incidence of infection into clinical outcomes. The resulting model was used to estimate the impact of vaccinating pre-school and school aged children with a live attenuated influenza vaccine. Clinical impact was quantified as the mean annual number of averted influenza infections and the related general practice consultations, hospitalisations and deaths, over a 15-year time horizon. The model adopts a realistic age structure (RAS), starting with population data for England and Wales in 1980, provided by the Office for National Statistics (ONS). These data are single year of age stratified population numbers [15].