US children living in and near poverty - Risk of vaccine-preventable diseases

Background: Poverty and factors associated with poverty are strong and pers istent barriers to childhood immunization. Substantive differences in cover age with basic vaccinations have been consistently observed over time betwe en children living in poverty and those who are not. Methods: The National Immunization Survey (NIS) uses a random-digit-dialing sample of telephone numbers in each state and in 28 urban areas. The NIS p rovides vaccination coverage information representative of all U,S. childre n aged 19 to 35 months. We categorized children in the NIS using Bureau of Census categories of poverty as follows: "above poverty" for household inco me greater than or equal to 125% of the federal poverty threshold for the h ousehold's size and composition; "near poverty," 100% to < 125% of the pove rty threshold; "intermediate poverty," 50% to < 100% of the poverty thresho ld; and "severe poverty," (50% of the poverty threshold. We described cover age with basic vaccinations from 1996 through 1999 by poverty category and compare coverage between children in poverty and above poverty. Results: From 1996 to 1999, estimated vaccination coverage with the basic v accine series was consistently higher among children living above the pover ty level than all other children. The difference in estimated vaccination c overage between children living in severe poverty and those living above po verty was 13.6 percentage points in 1996, and 10.0 percentage points in 199 9. Vaccination coverage with the series 4:3:1:3 among children living in ne ar poverty was similar to that of children living in poverty (74.7% vs 73.3 %, p=0.52). Estimated vaccination coverage increased significantly (p <0.05 ) between 1996 and 1999 for most antigens among children living above pover ty and among those living in intermediate and severe poverty. Vaccination c overage among children living in poverty increased significantly (P <0.05) between 1996 and 1999 in 1 of the 28 urban areas in the NIS, Conclusions: Conclusions: Low vaccination coverage among children living in and near pov erty is a persistent problem in the United States. Additional efforts are n eeded to improve coverage.