Philip Smith, ISD, CDC, MS E 62, 1600 Clifton Road, NE, Atlanta, GA, USA, Susan Y Chu, Centers for Disease Control and Prevention, National Immunization Program, 1600 Clifton Road, NE, MS E-52, Atlanta, USA, and Lawrence E. Barker, National Immunization Program, Centers for Disease Control, 1600 Clifton Road, Mailstop E-62, Atlanta, GA, USA.
BACKGROUND:
Despite efforts to increase vaccination coverage rates by removing barriers to receiving vaccinations, each year 1.4 million children 19-35 months of age are undervaccinated. Among these are children who received no vaccinations. Unvaccinated children are at greatly increased risk of acquiring a vaccine preventable disease (VPD). Those who acquire VPDs pose a risk for undervaccinated children.
OBJECTIVE:
To compare characteristics of unvaccinated and undervaccinated children, and provide estimates of the number of unvaccinated children by county.
METHOD:
We used 1995-2001 data from National Immunization Survey. Vaccination histories of children 19-35 months of age were ascertained from medical providers. Undervaccinated children received at least one dose of DTaP vaccine, polio vaccine, MMR vaccine, Hib vaccine, Hep B vaccine, or varicella vaccine, but did not receive all of the doses recommended for all of these vaccines. Unvaccinated children had no medical providers and received no vaccinations, or had providers who reported administering no vaccinations.
RESULT:
Undervaccinated children tended to be black or Hispanic, have an unmarried mother with £12yrs of education, and live in a household below poverty. Unvaccinated children tended to be white, have an older mother who had a college education, live in a household with a high income, and live in a household with ³4 children. Annually, 18,000 children were unvaccinated. The largest numbers of unvaccinated children lived in Los Angeles, Detroit, Orange Co, San Bernardino Co, San Diego, Fresno, Chicago, Westchester Co, Seattle, Pittsburgh, Dallas, Oklahoma City, Spokane, Boulder, Salt Lake, and Houston.
CONCLUSION:
Unvaccinated children have characteristics that are distinctly different from those of undervaccinated children. Unvaccinated children cluster geographically and may remain unvaccinated upon school entry, increasing the risk of spreading VPDs to both unvaccinated and undervaccinated children.
LEARNING OBJECTIVES:
To describe differences between unvaccinated and undervaccinated children.