Effectiveness and costs of combined influenza and pneumococcal vaccination in young children with recurrent respiratory tract infections: a general practice-based randomized controlled trial

In view of the considerable health-economic burden of recurrent RTIs in young children and few barriers to implementation of primary care-based vaccination, potential health and economic benefits of combined vaccination with recently developed trivalent cold-adapted intranasal influenza vaccine (CAIV) and conjugated pneumococcal vaccine (PCV7) warrants further study. We therefore aim to determine the effects of combined influenza and pneumococcal vaccination on the incidence of febrile RTI-episodes, antibiotic prescriptions and improvement of health-related quality-of-life in young children with recurrent RTIs. In a randomized, double-blind, placebo-controlled trial in primary care, 1,000 children aged between 12 and 72 months with >=4 episodes of febrile respiratory tract infections in the year preceding baseline will be studied. Subjects will be randomized to receive either CAIV/PCV7 (boostered by 23-valent PPV) or placebo. During a follow-up period of 24 months, clinical outcomes will be monitored by use of a computerized digital tympanic thermometer and parental diaries, physician forms and validated quality-of-life questionnaires for children. The primary outcome is defined as febrile illness (>38 ºCelsius) associated with at least one symptom/sign of RTI. Secondary outcomes include physician-diagnosed RTI and medication use, health-related quality-of-life scores as well as costs of treatment, and productivity loss by parents.