BACKGROUND:
Childhood vaccination is vital for controlling vaccine preventable diseases. Poverty has been identified as a barrier to childhood vaccination.

OBJECTIVE:
To examine childhood vaccination coverage by socioeconomic status (SES).

METHOD:
We investigated vaccine coverage among 19-35 month old children for each of the years 1999-2002 using National Immunization Survey data stratified by SES and maternal education. Coverage was defined using the 4:3:1:3 series (4+ doses of diphtheria and tetanus toxoids and pertussis vaccine, 3+ doses of any poliovirus vaccine, 1+ doses of measles-containing vaccine, and 3+ doses of Haemophilus infleunzae type b vaccine.) Socioeconomic status (SES) was defined using an income to federal poverty level ratio: severe poverty (ratio <50%), intermediate poverty (50 to <100%), near poverty (100- < 125%), low middle SES ( >125-300%), middle SES (>300-600%), upper SES (ratio > 600%).

RESULT:
Among children living below or near poverty, vaccination coverage was below 80% for all years (severe poverty, range=68-71%, intermediate poverty, range=72-74%, near poverty, range=70-77%). Vaccination coverage ranged from 75-79% for children in the low middle SES, but above 80% for children living in middle and upper SES households for all years (ranges 81-84% and 80-86% respectively). Children of mothers with >H.S. education living in middle and upper SES households had higher vaccination rates than children of mothers with less education living in similar households.

CONCLUSION:
Families with greater income and higher education may have greater exposure to resources that assists them in adopting vaccine-promoting behaviors. Strategies to increase childhood immunization rates among lower socioeconomic status households are needed.

LEARNING OBJECTIVES:
To better understand the affect of socioeconomic status on childhood immunization.