Missed Opportunities for Influenza Vaccination among Healthy Young Children

Background:
Despite expansion of pediatric influenza vaccine recommendations, only 21.3% of children aged 6-23 months were fully vaccinated during the 2006-2007 influenza season. While missed opportunities have been shown to decrease influenza vaccination coverage among high-risk children, the extent of missed opportunities for influenza coverage among the general population of young children is unknown.

Objectives:
To assess missed opportunities for 6-23 month old children in three geographically distinct US counties during the 2004-2005 season.

Methods:
A total of 1863 randomly selected 6-23 month old children presented at 46 physician practices during the 2004-2005 influenza season. Their charts were systematically reviewed to determine medical visit type, symptoms and diagnoses related to acute respiratory infections, and all vaccinations received. Children who presented with a serious medical illness were considered ineligible for vaccination. Missed opportunities were defined as a visit to the primary care practice by a child during 2004-2005 when the child was eligible but did not receive an influenza vaccination during the time period when a practice was administering vaccine. Vaccine availability spanned the first and last dates of influenza vaccination by practice. Missed opportunities were calculated for first and second vaccine doses.

Results:
The study population was 30.5% fully vaccinated. Most children (63.8%) had one or more missed opportunities for influenza vaccination during the period of vaccine availability. Among children with missed opportunities, influenza vaccination coverage was 12.9% for full vaccination. Most missed opportunities occurred at non-well child visits and at visits when no other vaccines were given. Eliminating all missed opportunities would have increased full vaccination coverage from 30.5% to 52.7%.

Conclusions:
Reducing missed opportunities would substantially increase vaccination coverage. Evidence-based strategies implemented in the practice setting such as flagging charts or computer notification to identify eligible children at every visit would reduce missed opportunities.