Uptake of Meningococcal Vaccine in Arizona School Children after Implementation of Immunization Requirements at School Entry

Simpson, Jennifer

BACKGROUND:

Meningitis and bacteremia due to Neisseria meningitidis are rare but potentially deadly diseases that can be prevented with immunization. In 2008, Arizona school immunization requirements were amended to include immunization of children 11 years or older with meningococcal vaccine before entering 6th grade. This study describes demographic community patterns in meningococcal vaccine uptake surrounding these school-entry requirement changes in Arizona.

METHODS:

Immunization records from the Arizona State Immunization Information System (ASIIS) were used to compare immunization rates in 11 and 12 year olds. Principle Component Analysis and hierarchical cluster analysis were used to identify and analyze demographic variables reported by the US 2010 Census.

RESULTS:

Adolescent meningococcal immunization rates in Arizona increased significantly after implementation of state-wide school entry immunization requirements. The increase in meningococcal vaccination rates among 11 and 12 year olds from 2007 to 2008 was statistically significant (p-value <0.0001) at the 95% confidence level. All demographic groups had significantly higher odds of an on-schedule vaccination after the school entry requirement change (OR range=5.57-12.81; p<0.0001), however, several county demographic factors were associated with a smaller degree of response in on-schedule vaccinations.

CONCLUSIONS:

Demographic groups associated with lower odds of on-schedule vaccination were those with higher poverty rates, more children under 18, fewer high-school graduates, and higher proportion of Native Americans. This analysis suggests that implementation of school immunization requirements resulted in increased meningococcal vaccination rates in Arizona, and the increase was variable based on demographic groups. The ASIIS was useful for assessing changes in immunization rates over time, and for determining demographic factors associated with vaccine up-take. Further study is required to identify appropriate methods to manage over-estimates of total population in immunization registry data.