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American Journal of Preventive Medicine | 2010

Progress toward eliminating disparities in vaccination coverage among U.S. children, 2000-2008.

Zhen Zhao; Elizabeth T. Luman

BACKGROUND The goal year for the Healthy People 2010 initiative is approaching. PURPOSE This article aims to assess progress toward reaching the overarching goal of eliminating disparities in vaccination coverage among young children in the U.S. METHODS Coverage for the 4:3:1:3:3:1 vaccine series (at least four doses of diphtheria-tetanus-pertussis, three poliovirus, one measles-mumps-rubella, three hepatitis B, three Haemophilus influenzae type B, and one varicella vaccine) was assessed among 185,516 children in the 2000-2008 National Immunization Surveys. Observed and adjusted disparities in coverage were evaluated for various sociodemographic groups previously associated with vaccination coverage. Linear trends in disparities were assessed. RESULTS In 2000, disparities among population segments were significant (p<0.05) for all sociodemographic factors assessed except provider participation in the Vaccines for Children program. By 2008, most disparities were smaller than those in 2000, and racial and urban/suburban/rural differences were reduced to levels below significance. Disparities between children living in suburban versus rural localities narrowed approximately 0.5% per year. Vaccination coverage increased substantially among children in all sociodemographic groups, although children without siblings were the only group to reach the 80% target by 2008. CONCLUSIONS Progress has been made toward eliminating vaccination coverage disparities among children in various sociodemographic groups in the U.S. As the end of the Healthy People 2010 goal period approaches, maintaining and advancing these reductions will require innovative strategies to reach underserved groups.


Vaccine | 2013

Trends in vaccination coverage disparities among children, United States, 2001–2010☆

Zhen Zhao; Philip J. Smith

INTRODUCTION One of two overarching goals of the Healthy People 2010 initiative was to eliminate health disparities. We evaluate trends in children vaccination coverage disparities by socio-demographic characteristics in the United States from 2001 through 2010. METHODS Disparities in vaccination coverage for the 4:3:1:3:3:1 vaccine series was assessed with National Immunization Survey (NIS) 2001-2010 data. The disparities between two categories of population were independently evaluated yearly from 2001 through 2010. RESULTS In 2001, 10 out of 12 disparities were significant (P-value <0.05). Six disparities were reduced from statistically significant in 2001 to not significant in 2010. Across 2001-2010, 8 disparities narrowed significantly; the average change in disparities per year were negative and ranged from -0.30% to -0.64% (P-value <0.05). CONCLUSIONS Significant success has been achieved in reducing disparities in vaccination coverage for young children among most of the major socio-demographic subpopulations in the United States by 2010.


Vaccine | 2011

Progress in newborn hepatitis B vaccination by birth year cohorts—1998–2007, USA

Zhen Zhao; Trudy V. Murphy; Lisa Jacques-Carroll

BACKGROUND In 1999, the American Academy of Pediatrics (AAP) and the U.S. Public Health Service (USPHS) issued a joint statement on thimerosal in vaccines, which advised clinicians to temporarily postpone the first dose of hepatitis B vaccine for infants born to hepatitis B surface antigen (HBsAg)-negative women. In 2005, the Advisory Committee on Immunization Practices (ACIP) updated the strategy to improve prevention of perinatal and early childhood hepatitis B virus (HBV) transmission. OBJECTIVES To evaluate the progress in hepatitis B birth dose vaccination coverage in birth year cohort from 1998 to 2007 and assess the impact of changes in ACIP recommendations on the birth dose coverage. METHODS Birth year cohort study of hepatitis B birth dose vaccination status of 200,865 children aged 19-35 months in the United States and by selected socio-demographic factors; percentage increases of hepatitis B birth dose vaccination coverage between two consecutive birth year cohorts from 1998 to 2007. RESULTS From 1998 to 1999, hepatitis B birth dose vaccination coverage declined overall in the United States and among selected socio-demographic groups (P<0.001). Conversely, from 1999 to 2007 hepatitis B birth dose vaccination coverage increased significantly by birth year cohort (P<0.001), from approximately 30% in the 1999 birth year cohort to approximately 60% in the 2007 birth year cohort. The first significant increase in hepatitis B birth dose vaccination coverage occurred from 2000 to 2001 birth year cohort. Coverage increases ranged from 8.4% to 11.9% (P<0.001) in the U.S. and across all socio-demographic strata. The second largest increase in hepatitis B birth dose vaccination coverage occurred from 2005 to 2006 birth year cohort in the U.S. and among almost all socio-demographic strata, ranging from 5.6% to 8.7% (P<0.001). Forty-one of the 50 states and the District of Columbia (80%) in the U.S. had increases in hepatitis B birth dose vaccination coverage from 2005 to 2006 birth year cohort. CONCLUSIONS The United States has made substantial progress in increasing hepatitis B birth dose vaccination and recovered from coverage declines associated with temporary postponement of the birth dose in 1999. The hepatitis B birth dose coverage in the U.S. remains substantially below the Healthy People 2020 target of 85%.


Vaccine | 2009

Trends in early childhood vaccination coverage: progress towards US Healthy People 2010 goals.

Zhen Zhao; Philip J. Smith; Elizabeth T. Luman

OBJECTIVES To evaluate trends in national vaccination coverage from 2000 to 2007 among children aged 19-35 months for at least four doses of diphtheria-tetanus-pertussis vaccine (4+DTaP), three doses of poliovirus vaccine (3+Polio), one dose of measles-mumps-rubella vaccine (1+MMR), three doses of Haemophilus influenzae type b vaccine (3+Hib), three doses of hepatitis B vaccine (3+HepB), one dose of Varicella vaccine (1+Var), and the standard vaccine series of these six vaccines (4:3:1:3:3:1). To predict vaccination coverage levels in 2008-2010 for those vaccines that have not yet reached the Healthy People 2010 coverage targets of 90% for individual vaccines and 80% for the vaccine series. METHODS Data were analyzed for 167,086 children aged 19-35 months in the 2000-2007 National Immunization Survey. Vaccination coverage trends were analyzed with weighted least squares linear regression models. Nonlinear Weibull and logarithmic regression models were fitted to these past results, and extrapolation was used to predict vaccination coverage levels for 4+DTaP, 1+Var, and the 4:3:1:3:3:1 series from 2008 to 2010. RESULTS From 2000 to 2007, observed vaccination coverage increased significantly for four of the six vaccines and the standard vaccine series, and reached the 90% target for 3+Polio, 1+MMR, 3+Hib, and 3+HepB. Increases in coverage were not significant for 1+MMR and 3+Hib; however, coverage for these vaccines was consistently>90% throughout the study period. Both Weibull and logarithmic regression models predicted that coverage with 1+Var and the 4:3:1:3:3:1 series will surpass the 2010 target by 2008, while coverage with 4+DTaP will fall short of the target at 86% in 2010. CONCLUSIONS The United States is well on the way toward reaching most of the Healthy People 2010 objectives for early childhood vaccination coverage. Enhanced efforts are needed to ensure that these trends continue, and to increase coverage with 4+DTaP.


Vaccine | 2016

Evaluation of potentially achievable vaccination coverage with simultaneous administration of vaccines among children in the United States

Zhen Zhao; Philip J. Smith; Holly A. Hill

BACKGROUND Routine administration of all age-appropriate doses of vaccines during the same visit is recommended for children by the National Vaccine Advisory Committee (NVAC) and the Advisory Committee on Immunization Practices (ACIP). METHODS Evaluate the potentially achievable vaccination coverage for ≥4 doses of diphtheria and tetanus toxoids and acellular pertussis vaccine (4+DTaP), ≥4 doses of pneumococcal conjugate vaccine (4+PCV), and the full series of Haemophilus influenzae type b vaccine (Hib-FS) with simultaneous administration of all recommended childhood vaccines. Compare the potentially achievable vaccination coverage to the reported vaccination coverage for calendar years 2001 through 2013; by state in the United States and by selected socio-demographic factors in 2013. The potentially achievable vaccination coverage was defined as the coverage possible for the recommended 4+DTaP, 4+PCV, and Hib-FS if missed opportunities for simultaneous administration of all age-appropriate doses of vaccines for children had been eliminated. RESULTS Compared to the reported vaccination coverage, the potentially achievable vaccination coverage for 4+DTaP, 4+PCV, and Hib-FS could have increased significantly (P<0.001), the vaccination coverage would have achieved the 90% target of Healthy People 2020 for the three vaccines beginning in 2005, 2008, and 2011 respectively. In 2013, the potentially achievable vaccination coverage increased significantly across all selected socio-demographic factors, potentially achievable vaccination coverage would have reached the 90% target for more than 51% of the states in the United States. CONCLUSIONS The findings in this study suggest that fully utilization of all opportunities for simultaneous administration of all age-eligible childhood doses of vaccines during the same vaccination visit is a critical strategy for achieving the vaccination coverage target of Healthy People 2020. Encouraging providers to deliver all recommended vaccines that are due at each visit by implementing client reminder and recall systems might decrease missed opportunities for simultaneous administration of childhood vaccines.


Vaccine | 2017

Missed opportunities for simultaneous administration of the fourth dose of DTaP among children in the United States

Zhen Zhao; Philip J. Smith; Holly A. Hill

BACKGROUND Simultaneous administration of all age-appropriate doses of vaccines is an effective strategy for raising vaccination coverage. Vaccination coverage for ≥4 dose of DTaP (diphtheria, tetanus toxoids, and acellular pertussis vaccine) among children 19-35months in the United States has not reached the Healthy People 2020 target of 90%. Risk factors for missed opportunities for simultaneous administration of the fourth dose of DTaP have not been investigated. METHODS A missed opportunity for simultaneous administration of the fourth dose of DTaP is defined as the failure to administer an age-eligible fourth dose of DTaP, and during the same age-eligible period for the fourth dose of DTaP other recommended and age-appropriate doses of vaccines are given to children. This study used 2001-2014 National Immunization Survey data to describe the trend in missed opportunities for simultaneous administration of the fourth dose of DTaP from 2001 through 2014, assess the prevalence of children who missed opportunities for simultaneous administration of the fourth dose of DTaP by selected factors, and recognize significant risk factors for missed opportunities for simultaneous administration of the fourth dose of DTaP. RESULTS From 2001 to 2014, the prevalence of missed opportunities for simultaneous administration of the fourth dose of DTaP among children 19-35months in the United States ranged from 5.7% to 9.0%; across 13 factors considered, the prevalence of missed opportunities varied from 3.3% to 22.9%. Children who were late in receiving the first to third dose of DTaP had significantly higher prevalence of missed opportunities for simultaneous administration of the fourth dose of DTaP than children who received these doses on-time, with adjusted prevalence ratios for late vs. on-time of 1.7, 1.6, and 3.2, and all P-value<0.01. CONCLUSIONS Improving on-time vaccination of the third dose of DTaP could substantially reduce missed opportunities for simultaneous administration of the fourth dose of DTaP.


Preventive Medicine | 2013

Which newborns missed the hepatitis B birth dose vaccination among U.S. children

Zhen Zhao; Trudy V. Murphy

OBJECTIVES Hepatitis B birth dose vaccination is a critical step in preventing perinatal hepatitis B virus infection. This study assesses the prevalence of children who missed the birth dose of hepatitis B vaccination and identifies socio-demographic factors associated with non-receipt of the birth dose among children in the United States. METHODS A survey observation study was conducted with the national representative sample of 17,053 U.S. children aged 19-35 months obtained from the 2009 National Immunization Survey. Categorical data analysis and multivariable logistic regression in the context of complex sample survey were applied to evaluate the prevalence and determine the independent risk factors. RESULTS 39.2% of children missed the birth dose of hepatitis B vaccination. Children who reside in states without a universal hepatitis B vaccine supply policy, are not covered by health insurance, and have only 1 vaccination provider are significantly associated with non-receipt of the birth dose hepatitis B vaccination. CONCLUSIONS Children who reside in states without a universal hepatitis B vaccine supply policy, and who are not covered by health insurance are two important modifiable risk factors for not receiving the birth dose hepatitis B vaccination. Future intervention studies could be needed to help control those modifiable risk factors.


Vaccine | 2012

WITHDRAWN: Trends in vaccination coverage disparities among children, United States, 2001–2010

Zhen Zhao; Philip J. Smith

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.


JAMA Pediatrics | 2009

Hepatitis B vaccination coverage in newborns and vaccine supply policy.

Lisa Jacques-Carroll; Susan Wang; Zhen Zhao; Tasneem Malik; Felicita David


Archive | 2017

Total Survey Error Assessment for Sociodemographic Subgroups in the 2012 U.S. National Immunization Survey

Kirk M. Wolter; Vicki Pineau; Benjamin Skalland; Wei Zeng; James A. Singleton; Meena Khare; Zhen Zhao; David Yankey; Philip J. Smith

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Philip J. Smith

National Center for Immunization and Respiratory Diseases

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Elizabeth T. Luman

National Center for Immunization and Respiratory Diseases

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Holly A. Hill

National Center for Immunization and Respiratory Diseases

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Meena Khare

Centers for Disease Control and Prevention

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Trudy V. Murphy

Centers for Disease Control and Prevention

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David Yankey

National Center for Immunization and Respiratory Diseases

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James A. Singleton

National Center for Immunization and Respiratory Diseases

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Lisa Jacques-Carroll

National Center for Immunization and Respiratory Diseases

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