Seasonal Influenza Vaccination Reminders for Children with High-Risk Conditions: A Registry-Based Randomized Trial

Background: Children with chronic conditions have an increased risk of complications from influenza and have low influenza vaccination rates. Purpose: To assess the feasibility and effectiveness of using a statewide immunization information system (IIS) for seasonal influenza vaccine reminders from local health departments (LHDs) targeting children with high-risk conditions. Design: A randomized community intervention. Setting/participants: The study was conducted in a population of 3618 children aged 24–60 months with a high-risk condition residing in three Michigan counties. Children were identifıed using a statewide IIS in October 2008.