U.S. children living in and near poverty: risk of vaccine-preventable diseases

Acceptance of COVID-19 vaccine and determinant factors in the Iranian population: a web-based study

BACKGROUND

Iran had a high rate of death in several COVID 19 waves. Vaccination is a method for prevention and control of the COVID-19 pandemic. Success in controlling the pandemic is not solely dependent on the effectiveness of the vaccines. It is also dependent on the global acceptance and vaccine coverage rate. This study aimed to determine the acceptance rate of COVID-19 vaccination in the Iranian population and the factors affecting it.

METHODS AND MATERIALS

This study was a cross-sectional research on 1564 Iranian people above 18. Study data were collected using a web-based questionnaire and analyzed using linear regression analysis and logistics at a significance level of 0.05 using SPSS.

RESULTS

Approximately 70% of the participants reported acceptance of the vaccines. Ten percent of the people were against and 20% were hesitant to get vaccinated. The results showed that risk perception (P = .003), Knowledge of the disease (P < .001), trust in the health system (P < .001), attitude towards vaccination (P < .001), and vaccination literacy (P < .001) were predictors of vaccine acceptance. People with higher levels of education and mistrust towards the health system had a reduced vaccine acceptance rate.

CONCLUSIONS

The acceptance rate of the COVID-19 vaccine in Iran was higher than in the other countries in the Middle East. Extensive interventions are important to increase the trust in the health system and improve the knowledge of vaccine efficacy and literacy.

Reasons for being unsure or unwilling regarding intention to take COVID-19 vaccine among Japanese people: A large cross-sectional national survey

Background

Identifying and understanding reasons for being unsure or unwilling regarding intention to be vaccinated against coronavirus disease (COVID-19) may help to inform future public health messages aimed at increasing vaccination coverage. We analyzed a broad array of individual's psychological dispositions with regard to decision-making about COVID-19 vaccination in Japan.

Methods

A nationally representative cross-sectional web survey was conducted with 30053 Japanese adults aged 20 years or older at the end of February 2021. In addition to the question on the individual's intention to be vaccinated against COVID-19, respondents were asked about their sociodemographic, health-related, and psychological characteristics as well as information sources about COVID-19 and their levels of trust. Also, those who responded ‘not sure’ or ‘no’ regarding intention to take COVID-19 vaccine were asked why. Multinomial logistic regression with sparse group Lasso (Least Absolute Shrinkage and Selection Operator) penalty was used to compute adjusted odds ratios for factors associated with the intention (not sure/no versus yes).

Findings

The percentages of respondents who answered ‘not sure’ or ‘no’ regarding intention to be vaccinated against COVID-19 vaccine were 32.9% and 11.0%, respectively. After adjusting for covariates, the perceived risks of COVID-19, perceived risk of a COVID-19 vaccine, perceived benefits of a COVID-19 vaccine, trust in scientists and public authorities, and the belief that healthcare workers should be vaccinated were significantly associated with vaccination intention. Several sources of information about COVID-19 were also significantly associated with vaccination intention, including physicians, nurses, and television, medical information sites with lower odds of being unsure or unwilling, and internet news sites, YouTube, family members, and scientists and researchers with higher odds. The higher the level of trust in television as a source of COVID-19 information, the higher the odds of responding ‘not sure’ (odds ratio 1.11, 95% confidence interval 1.01–1.21). We also demonstrated that many respondents presented concerns about the side effects and safety of a COVID-19 vaccine as a major reason for being unsure or unwilling. To decide whether or not to get the vaccine, many respondents requested more information about the compatibilities between the vaccine and their personal health conditions, whether other people had been vaccinated, the effectiveness of vaccines against variants, and doctors’ recommendations.

Interpretation

Our findings suggest that public health messaging based on the sociodemographic and psychological characteristics of those who are unsure or unwilling regarding intention to be vaccinated against COVID-19 vaccine may help to increase vaccine uptake amongst this population.

Funding

The present work was supported in part by a grant from the Ministry of Health, Labour and Welfare of Japan (H29-Gantaisaku-ippan-009).

Psychological characteristics associated with COVID-19 vaccine hesitancy and resistance in Ireland and the United Kingdom

Identifying and understanding COVID-19 vaccine hesitancy within distinct populations may aid future public health messaging. Using nationally representative data from the general adult populations of Ireland (N = 1041) and the United Kingdom (UK; N = 2025), we found that vaccine hesitancy/resistance was evident for 35% and 31% of these populations respectively. Vaccine hesitant/resistant respondents in Ireland and the UK differed on a number of sociodemographic and health-related variables but were similar across a broad array of psychological constructs. In both populations, those resistant to a COVID-19 vaccine were less likely to obtain information about the pandemic from traditional and authoritative sources and had similar levels of mistrust in these sources compared to vaccine accepting respondents. Given the geographical proximity and socio-economic similarity of the populations studied, it is not possible to generalize findings to other populations, however, the methodology employed here may be useful to those wishing to understand COVID-19 vaccine hesitancy elsewhere.

The Association between Parental Involvement Behavior and Self-Esteem among Adolescents Living in Poverty: Results from the K-CHILD Study

It is not yet known why some adolescents living in poverty show high self-esteem, while others do not. Parental involvement may be an important determinant to promote self-esteem among adolescents living in poverty. The aim of this study is to explore better parenting involvement behavior to promote self-esteem among adolescents living in poverty. Participants included fifth-, eighth-, and 11th-grade students living in Koichi prefecture, Japan. The participants were part of the Kochi Child Health Impact of Living Difficulty (K-CHILD) study, in 2016 (n = 10,784). Participants completed a questionnaire with questions about socioeconomic status and 14 parental involvement behaviors, including 9 specific kinds of parental interactions with their child (e.g., talking about school life), and 5 elements related to parental care for their child's physical health (e.g., access to health care). The numbers of parental involvement behaviors, parental interactions with their child, and parental care for their child's physical health were treated as continuous and quartile, to see the association. Overall, the study showed that the larger the number of parental involvement behaviors, the higher the self-esteem score of their off-spring (p < 0.01) among both adolescents living in poverty and not living in poverty, in which interaction between poverty and parental involvement behaviors was not significant. Both parental interaction with their child and parental care for their child's physical health were associated with higher self-esteem, in which parental interaction with their child had a larger effect than parental care for their child's physical health. To empower adolescents in poverty, caregivers need to provide both parental interaction with the child and parental care for the child's physical health.

Hepatitis B Birth Dose: First Shot at Timely Early Childhood Vaccination

INTRODUCTION

Current U.S. recommendations state that newborns weighing ≥2,000 grams should receive a birth dose of hepatitis B vaccine, yet approximately one quarter do not receive this first dose as scheduled. The relationship between timely receipt of the first hepatitis B vaccine and other early childhood vaccines remains unclear.

METHODS

Washington State newborns (birth weight ≥2,000 grams) who received birth hospitalization care at an urban academic medical center between 2008 and 2013 were included. Multivariable logistic regression was used to assess whether hepatitis B vaccine receipt during the birth hospitalization was associated with completing the seven-vaccine series by 19 months, adjusting for select sociodemographic, clinical, and birth hospitalization characteristics. Analyses were conducted in 2017-2018.

RESULTS

Of the 9,080 study participants, 75.5% received hepatitis B vaccine during the birth hospitalization, and 53.6% completed the seven-vaccine series by 19 months. Overall, 60.0% of infants vaccinated against hepatitis B during the birth hospitalization completed the seven-vaccine series by 19 months compared with 33.8% of those who were unvaccinated at discharge (p<0.001). The odds of series completion were nearly 3 times higher among infants who received versus did not receive hepatitis B vaccine during the birth hospitalization (AOR=2.92, 95% CI=2.61, 3.26).

CONCLUSIONS

Infants who received hepatitis B vaccine during their birth hospitalization had higher odds of receiving all recommended vaccines by 19 months independent of other factors associated with vaccine receipt. Understanding the factors that influence this first parental vaccine decision and how hepatitis B vaccine delay or declination may affect subsequent vaccination requires further research.

Pathway of the Association Between Child Poverty and Low Self-Esteem: Results From a Population-Based Study of Adolescents in Japan

Child poverty leads to various negative consequences, including low self-esteem, which is a risk factor for mental illness, suicide, or poor academic achievement. However, little is known about why child poverty leads to low self-esteem. We aimed to elucidate the association of child poverty and low self-esteem based on the ecological model, which includes family-level, school-level, and community-level factors. Data were obtained from the Adachi Child Health Impact of Living Difficulty (A-CHILD) study in 2016, and participants included 1,652 children in fourth grade (534 pairs), sixth grade (530 pairs), and eighth grade (588 pairs) living in Adachi City, Tokyo, Japan. A questionnaire survey was implemented to assess child poverty, parental mental health, parental involvement with children, parental social capital by caregivers, and self-esteem and school social capital by children. The structural equation model was applied to elucidate the association between child poverty and low self-esteem, using family-level (parental mental health and parental involvement with children), school-level (school social capital), and community-level (parental social capital) factors. Child poverty was associated with low self-esteem. Child poverty leads to poor parental involvement, which can be indirectly associated with poor parental mental health and poor parental social capital, and poor parental involvement was directly or indirectly associated with low self-esteem through poor school social capital. To mitigate the impact of child poverty on low self-esteem, comprehensive health policies targeting family-level (parental mental health and parental involvement with children), school-level (school social capital), and community-level (parental social capital) factors may be effective.

Early-life Medicaid Coverage and Intergenerational Economic Mobility

New data reveal significant variation in economic mobility outcomes across U.S. localities. This suggests that social structures, institutions, and public policies-particularly those that influence critical early-life environments-play an important role in shaping mobility processes. Using new county-level estimates of intergenerational economic mobility for children born between 1980 and 1986, we exploit the uneven expansions of Medicaid eligibility across states to isolate the causal effect of this specific policy change on mobility outcomes. Instrumental-variable regression models reveal that increasing the proportion of low-income pregnant women eligible for Medicaid improved the mobility outcomes of their children in adulthood. We find no evidence that Medicaid coverage in later childhood years influences mobility outcomes. This study has implications for the normative evaluation of this policy intervention as well as our understanding of mobility processes in an era of rising inequality.

High resolution age-structured mapping of childhood vaccination coverage in low and middle income countries

BACKGROUND

The expansion of childhood vaccination programs in low and middle income countries has been a substantial public health success story. Indicators of the performance of intervention programmes such as coverage levels and numbers covered are typically measured through national statistics or at the scale of large regions due to survey design, administrative convenience or operational limitations. These mask heterogeneities and 'coldspots' of low coverage that may allow diseases to persist, even if overall coverage is high. Hence, to decrease inequities and accelerate progress towards disease elimination goals, fine-scale variation in coverage should be better characterized.

METHODS

Using measles as an example, cluster-level Demographic and Health Surveys (DHS) data were used to map vaccination coverage at 1 km spatial resolution in Cambodia, Mozambique and Nigeria for varying age-group categories of children under five years, using Bayesian geostatistical techniques built on a suite of publicly available geospatial covariates and implemented via Markov Chain Monte Carlo (MCMC) methods.

RESULTS

Measles vaccination coverage was found to be strongly predicted by just 4-5 covariates in geostatistical models, with remoteness consistently selected as a key variable. The output 1 × 1 km maps revealed significant heterogeneities within the three countries that were not captured using province-level summaries. Integration with population data showed that at the time of the surveys, few districts attained the 80% coverage, that is one component of the WHO Global Vaccine Action Plan 2020 targets.

CONCLUSION

The elimination of vaccine-preventable diseases requires a strong evidence base to guide strategies and inform efficient use of limited resources. The approaches outlined here provide a route to moving beyond large area summaries of vaccination coverage that mask epidemiologically-important heterogeneities to detailed maps that capture subnational vulnerabilities. The output datasets are built on open data and methods, and in flexible format that can be aggregated to more operationally-relevant administrative unit levels.

Role of health determinants in a measles outbreak in Ecuador: a case-control study with aggregated data

BACKGROUND

In 2011-2012, an outbreak of measles occurred in Ecuador. This study sought to ascertain which population characteristics were associated.

METHODS

Case-control study of aggregate data. The unit of analysis was the parish (smallest geographic division). The national communicable disease surveillance database was used to identify 52 case parishes (with at least one confirmed case of measles) and 972 control parishes (no cases of measles). A hierarchical model was used to determine the association of measles with population characteristics and access to health care.

RESULTS

Case parishes were mostly urban and had a higher proportion of children under 1 year of age, heads of household with higher educational attainment, larger indigenous population, lower rates of measles immunization, and lower rates of antenatal care visit attendance. On multivariate analysis, associations were found with educational attainment of head of household ≥8 years (OR: 0.29; 95%CI 0.15-0.57) and ≥1.4% indigenous population (OR: 3.29; 95%CI 1.63-6.68). Antenatal care visit attendance had a protective effect against measles (OR: 0.98; 95%CI 0.97-0.99). Measles vaccination was protective of the outbreak (OR: 0.97; 95%CI 0.95-0.98). The magnitude of these associations was modest, but represents the effect of single protective factors, capable of acting at the population level regardless of socioeconomic, biological, and environmental confounding factors.

CONCLUSION

In Ecuador, the parishes with the highest percentage of indigenous populations and those with the lowest vaccination coverage were the most vulnerable during the measles outbreak.

The Vaccination Kuznets Curve: Do vaccination rates rise and fall with income?

This paper presents a new stylized fact about the relationship between income and childhood vaccination. It shows vaccination rates first rise but then fall as income increases. This pattern is observed in WHO country-level panel data, and in US county-level panel and individual-level repeated cross-section data. This data pattern suggests that both low and high-income parents are less likely to follow the standard vaccination schedule, and that such behavior is reflected in the vaccination rate at the population level. I provide several alternative explanations as to why we observe this data pattern, including avoidance measures, medical care, and social segregation.

Interventions to increase pediatric vaccine uptake: An overview of recent findings

Although much is known about factors contributing to variation in pediatric immunization uptake, there is a need for synthesis of effective vaccine promotion strategies. With growing public health concern on how to best sustain high pediatric immunization rates, and improve where the rates are suboptimal, this review offers evidence gathered from several studies on the achievement of these goals. We identified and analyzed reported findings on childhood (primarily ≤ 7 years) immunization outcomes from tested intervention strategies that focused on parents, guardians, and caregivers, as well as providers, clinics/practices, and communities. The findings suggest that targeted and tailored interventions offer substantial possibilities, especially in a combined manner. We describe promising intervention models that have been operationalized with success and provide evidence for scalability across contexts. Moreover, they are sensitive to parents' and providers' needs, are feasibly integrated in daily clinical practice, and account for broader community concerns and issues.

Maternal Attitudes and Other Factors Associated with Infant Vaccination Status in the United States, 2011-2014

OBJECTIVE

To assess the role of maternal attitudes and other factors associated with infant vaccination status.

STUDY DESIGN

Data on reported vaccination status were analyzed from a nationally representative prospective survey of mothers of 2- to 6-month-old infants. Weighted univariate and multiple logistic regression analyses were conducted. Latent profile analysis of mothers reporting nonimmunized infants identified distinct groups, RESULTS: Of 3268 mothers, 2820 (weighted 86.2%), 311 (9.1%), and 137 (4.7%), respectively, reported their infant had received all, some, or no recommended vaccinations for age. Younger infants and infants with younger mothers were more likely to have received no vaccinations. Mothers with neutral and negative attitudes toward vaccination were >3 (aOR 3.66, 95% CI 1.80-7.46) and 43 times (aOR 43.23, 95% CI 20.28-92.16), respectively, more likely than mothers with positive attitudes to report their infants had received no vaccinations. Two subgroups of mothers reporting that their infants had received no vaccinations were identified: group A (52.5%) had less than positive attitudes and less than positive subjective norms about vaccination (ie, perceived social pressure from others); group B (47.5%) had positive attitudes and positive subjective norms. Group A mothers were more likely to be white (76.1% vs 48.3%, P?=?.002), more educated (43.5% vs 35.4% college or higher, P?=?.02), and to exclusively breastfeed (74.9% vs. 27.3%, P?<?.001).

CONCLUSIONS

Although access barriers can result in nonvaccination, less than positive maternal attitude toward vaccination was the strongest predictor. Strategies to improve vaccination rates must focus on both improved access and better understanding of factors underlying maternal attitudes.

The distribution of hepatitis B virus exposure and infection in a population-based sample of U.S. Hispanic adults

Little is known regarding the prevalence and distribution of hepatitis B virus (HBV) infection in U.S. Hispanics/Latinos. We sought to determine the prevalence of HBV exposure (serum HBV core antibody; anti-HBc), active HBV infection (serum HBV surface antigen; HBsAg), and vaccine-induced HBV immunity (antibody against HBV surface antigen; anti-HBs) in U.S. Hispanics/Latinos and consider how these data inform clinical screening recommendations. Our analysis included 11,999 women and men of the Hispanic Community Health Study/Study of Latinos (HCHS/SOL), a population-based, household survey in four urban communities (Bronx, NY; Miami, FL; Chicago, IL; and San Diego, CA) of U.S. civilian, noninstitutionalized self-identifying Hispanic/Latino adults ages 18-74. Vaccine-induced immunity was defined as detection of anti-HBs, but not anti-HBc. However, if anti-HBc were present, it was considered evidence of exposure to HBV, with detection of HBsAg used to distinguish those with active HBV infection. Mean age was 45.7 years, and 7,153 were women. Vaccine-induced immunity was greatest among those ages 18-29 years (60.2% in women, 54% in men) and decreased with increasing age, regardless of country of birth. The prevalence of active HBV infection was 0.29% (95% confidence interval: 0.19-0.43), but varied by country of birth. Those born in the Dominican Republic had the highest prevalence of HBV exposure (20.3% in women, 29.7% in men) and active HBV infection (0.95%).

CONCLUSIONS

The overall age-standardized prevalence of active HBV infection in Hispanic/Latino adults (0.29%) was no different from the general U.S. population estimate (0.27%) and did not exceed 2%, regardless of country of birth. These data do not support targeting HBV screening to US Hispanic/Latino adults based upon background.

Impact of Subsidies and Socioeconomic Status on Varicella Vaccination in Greater Tokyo, Japan

BACKGROUND

Although the control of varicella outbreaks is an important health issue, cost could present a major barrier for vaccination. The aim of this study is to investigate the association of vaccine subsidies and caregivers' socioeconomic status with varicella vaccine coverage of their children in Greater Tokyo, Japan, before the period that varicella vaccination was included in routine immunization program.

METHODS

Participants were recruited from two different cities. In Chiba city, parents of 18-month-old infants (N = 378) undergoing a medical examination in July 2013 were recruited at a clinic where no subsidy for varicella immunization was provided. In Nishitokyo city, parents of 24- to 30-month-old children (N = 315) undergoing a health checkup in July and August 2013 were recruited at a clinic where a partial subsidy was provided. The association between household income and varicella immunization was investigated by multivariate logistic regression stratified by city.

RESULTS

Vaccine coverage was 61.0% in Chiba city and 73.3% in Nishitokyo city. In Chiba city, odds ratios of middle and high household income for varicella immunization were 4.22 [95% confidence interval (CI): 1.65-10.7] and 5.94 (95% CI: 1.89-18.6), respectively, compared to low household income. However, household income was not associated with varicella vaccination in Nishitokyo city. Neither working status nor education was associated with vaccination in both cities.

CONCLUSION

While household income was associated with high vaccine coverage in the city with no vaccine subsidy, this association was not observed in the city where the subsidy was given, which suggests that cost is a barrier for varicella immunization. Thus, in countries where varicella vaccination is not included in routine immunization programs, introducing subsidies nationwide or routine immunization programs for varicella vaccination would be an important approach to eliminate inequality in vaccine coverage.

A current and historical perspective on disparities in US childhood pneumococcal conjugate vaccine adherence and in rates of invasive pneumococcal disease: Considerations for the routinely-recommended, pediatric PCV dosing schedule in the United States

Previous research has suggested that reducing the US 4-dose PCV13 schedule to a 3-dose schedule may provide cost savings, despite more childhood pneumococcal disease. The study also stressed that dose reduction should be coupled with improved PCV adherence, however, US PCV uptake has leveled-off since 2008. An estimated 24–36% of US children aged 5–19 months are already receiving a reduced PCV schedule (i.e., missing ≥1 dose). This raises a practical concern that, under a reduced, 3-dose schedule, a similar proportion of children may receive ≤2 doses. It is also unknown if a reduced, 3-dose PCV schedule in the United States will afford the same disease protection as 3-dose schedules used elsewhere, given lower US PCV adherence. Finally, more assurance is needed that, under a reduced schedule, racial, socioeconomic, and geographic disparities in PCV adherence will not correspond with disproportionately higher rates of pneumococcal disease among poor or minority children.

Childhood vaccination coverage rates among military dependents in the United States

BACKGROUND AND OBJECTIVES

The Military Health System provides universal coverage of all recommended childhood vaccinations. Few studies have examined the effect that being insured by the Military Health System has on childhood vaccination coverage. The purpose of this study was to compare the coverage of the universally recommended vaccines among military dependents versus other insured and uninsured children using a nationwide sample of children.

METHODS

The National Immunization Survey is a multistage, random-digit dialing survey designed to measure vaccination coverage estimates of US children aged 19 to 35 months old. Data from 2007 through 2012 were combined to permit comparison of vaccination coverage among military dependent and all other children.

RESULTS

Among military dependents, 28.0% of children aged 19 to 35 months were not up to date on the 4:3:1:3:3:1 vaccination series excluding Haemophilus influenzae type b vaccine compared with 21.1% of all other children (odds ratio: 1.4; 95% confidence interval: 1.2-1.6). After controlling for sociodemographic characteristics, compared with all other US children, military dependent children were more likely to be incompletely vaccinated (odds ratio: 1.3; 95% confidence interval: 1.1-1.5).

CONCLUSIONS

Lower vaccination coverage rates among US military dependent children might be due to this population being highly mobile. However, the lack of a military-wide childhood immunization registry and incomplete documentation of vaccinations could contribute to the lower vaccination coverage rates seen in this study. These results suggest the need for further investigation to evaluate vaccination coverage of children with complete ascertainment of vaccination history, and if lower immunization rates are verified, assessment of reasons for lower vaccination coverage rates among military dependent children.

Failure to return: parental, practice, and social factors affecting missed immunization visits for urban children

OBJECTIVE

To assess parental, practice, and social factors associated with missed immunization visits by young, urban children.

STUDY DESIGN

Parents of children ≤ 36 months(n = 705) were surveyed. The primary outcome was missed immunization visit, by parental report. Key parent, practice, and social factors were assessed using hierarchical logistical regression. Results. Families were predominantly Latino and publicly insured. Parents who rescheduled (adjusted odds ratio [AOR] = 3.27; 95% confidence interval [95% CI] = 1.76-6.09) or had problems scheduling appointments (AOR = 4.00; 95% CI = 1.49-10.75) were more likely to miss an immunization visit, as were those with vaccine safety fears (AOR = 3.76; 95% CI = 1.23-11.5) or more limited communication with their provider (AOR = 2.38; 95% CI = 1.05-5.36). Having friends and families with positive immunization views was protective (AOR = 0.030; 95% CI = 0.002-0.41).

CONCLUSION

This study highlights factors that may help urban families keep immunization visits: open communication with providers, flexibility in scheduling appointments, and individual and community education.

Parent perspectives on the design of a personal online pediatric immunization record

OBJECTIVE

To examine desired characteristics of an online immunization record for parents from a predominantly Latino, low-income population.

METHODS

Four focus groups were conducted with parents (n = 29) from an urban, primarily Latino, low-income population in New York. The data were collected and analyzed during winter 2008-2009.

RESULTS

Participants expressed interest in using an online immunization record that has the ability to show a child's immunization status and to access consumer health information related to vaccinations. Participants suggested that the online record be translated into multiple languages and provide user-friendly interfaces. Participants were enthusiastic about the benefits offered by the online immunization record, highlighting having an electronic copy of their child's immunization record available. Concerns over disclosing personal information were raised, and safeguards to protect confidentiality were requested.

CONCLUSIONS

If concerns about privacy are adequately addressed, parents of low-income, urban children are likely to use and benefit from an online immunization record.

Vaccination coverage and its determinants among migrant children in Guangdong, China

Background

Guangdong province attracted more than 31 million migrants in 2010. But few studies were performed to estimate the complete and age-appropriate immunization coverage and determine risk factors of migrant children.

Methods

1610 migrant children aged 12–59 months from 70 villages were interviewed in Guangdong. Demographic characteristics, primary caregiver’s knowledge and attitude toward immunization, and child’s immunization history were obtained. UTD and age-appropriate immunization rates for the following five vaccines and the overall series (1:3:3:3:1 immunization series) were assessed: one dose of BCG, three doses of DTP, OPV and HepB, one dose of MCV. Risk factors for not being UTD for the 1:3:3:3:1 immunization series were explored.

Results

For each antigen, the UTD immunization rate was above 71%, but the age-appropriate immunization rates for BCG, HepB, OPV, DPT and MCV were only 47.8%, 45.1%, 47.1%, 46.8% and 37.2%, respectively. The 1st dose was most likely to be delayed within them. For the 1:3:3:3:1 immunization series, the UTD immunization rate and age-appropriate immunization rate were 64.9% and 12.4% respectively. Several factors as below were significantly associated with UTD immunization. The primary caregiver’s determinants were their occupation, knowledge and attitude toward immunization. The child’s determinants were sex, Hukou, birth place, residential buildings and family income.

Conclusions

Alarmingly low immunization coverage of migrant children should be closely monitored by NIISS. Primary caregiver and child’s determinants should be considered when taking measures. Strategies to strengthen active out-reach activities and health education for primary caregivers needed to be developed to improve their immunization coverage.

Effect of vaccination coordinators on socioeconomic disparities in immunization among the 2006 Connecticut birth cohort

OBJECTIVES

We examined socioeconomic status (SES) disparities and the influence of state Immunization Action Plan-funded vaccination coordinators located in low-SES areas of Connecticut on childhood vaccination up-to-date (UTD) status at age 24 months.

METHODS

We examined predictors of underimmunization among the 2006 birth cohort (n = 34,568) in the state's Immunization Information System, including individual demographic and SES data, census tract SES data, and residence in an area with a vaccination coordinator. We conducted multilevel logistic regression analyses.

RESULTS

Overall, 81% of children were UTD. Differences by race/ethnicity and census tract SES were typically under 5%. Not being UTD at age 7 months was the strongest predictor of underimmunization at age 24 months. Among children who were not UTD at age 7 months, only Medicaid enrollment (adjusted odds ratio [AOR] = 0.6; 95% confidence interval [CI] = 0.5, 0.7) and residence in an area with a vaccination coordinator (AOR = 0.7; 95% CI = 0.6, 0.9) significantly decreased the odds of subsequent underimmunization.

CONCLUSIONS

SES disparities associated with underimmunization at age 24 months were limited. Efforts focused on vaccinating infants born in low SES circumstances can minimize disparities.

Do income inequality and social capital associate with measles-containing vaccine coverage rate?

OBJECTIVE

We investigated the association between income inequality and social capital with measles-containing vaccine (MCV) coverage rates in Japan.

METHODS

MCV coverage data for all 1750 municipalities were collected from statistics publicized by the Ministry of Health, Labour and Welfare of Japan in 2010. Prefectural Gini coefficients in 2009 (an indicator of income inequality) and social capital indicators (including voting rates, volunteer rates at the prefectural level, and move-in ratios at the municipal level) were linked to MCV coverage using a multilevel analysis adjusting for covariates (population, age distribution, average income, average number of household members).

RESULTS

Coverage of the first dose of MCV (MCV1), and second dose (MCV2), decreased by 3.98% (95% confidence interval [CI]: 0.26-7.71) and 4.28% (95% CI: 0.60-7.60) per each 0.1-unit increase in Gini coefficients within large municipalities (with a population 50,000 or more), respectively. Conversely, coverage of MCV2 increased by 0.26% (95% CI: 0.08-0.45) per 1% increase in voting rate within large municipalities. Volunteer rates were inversely associated with MCV2 coverage within large municipalities. Move-in ratios at the municipal level were inversely associated with MCV2 coverage within medium-sized municipalities (with a population between 10,000 and 50,000).

CONCLUSIONS

While higher income inequality at a prefectural level was associated with lower MCV coverage rates, higher social capital was associated with higher coverage in large municipalities. To enhance MCV coverage in Japan, we recommend that income inequality be addressed and social capital boosted at the prefectural level.

Feasibility of a randomized controlled trial to evaluate Text Reminders for Immunization Compliance in Kids (TRICKs)

OBJECTIVE

To pilot test the Text Reminders for Immunization Compliance in Kids (TRICKs) program to evaluate its feasibility and potential to increase immunization coverage.

DESIGN

Randomized controlled trial (RCT).

SETTING

Pediatric clinic.

PARTICIPANTS

Parents of newborns being discharged from a local hospital who intended to seek child health care at the University-sponsored pediatric resident and faculty clinic.

INTERVENTION

Text message immunization reminders prior to immunization due dates.

MAIN OUTCOME MEASURES

Receipt and timeliness of immunizations at 2, 4 and 6 months of age.

RESULTS

Participants (N=90) were English (83%) or Spanish (17%) speaking. The majority were female (83%), on public insurance (59%), and had adequate health literacy (96%). Parents were married or a member of an unmarried couple (62%). Over 66% had a high school diploma or less. Greater numbers of intervention children received immunizations and were "on time" using per protocol analysis; though not statistically significance. Limitations include sample size, problematic text messaging software, and loss of phone service at 7 months for 40% of intervention parents. However, post-intervention interviews (N=18) indicated strong support for TRICKs; 83% found the text message reminders very helpful and 17% somewhat helpful.

DISCUSSION

Pilot testing allowed us to assess processes, including recruitment, retention, and software, which will increase the success of an RCT. Software with built-in backup systems is needed for follow-up when mobile service is interrupted. However, in spite of limitations, immunization rates were higher in the text message reminder group, though not statistically significant. Parent support and interest was high. A fully powered RCT is needed with follow-up over the full 4-3-1-3-3-1 series. Based on our results, for 80% power where we expected 90% compliance in the intervention group and 80% in the control group we need 219 per group, plus increases to address drop out and loss of follow-up.

Medicaid reimbursement and the uptake of adolescent vaccines

BACKGROUND

In light of low adolescent vaccination rates, state-level policies that could improve vaccine coverage should be evaluated. Approximately 1/3 of adolescents are eligible, primarily through Medicaid enrollment, to receive vaccines from state-administered Vaccines for Children (VFC) programs. We investigated whether Medicaid reimbursement, the scope of implementation of VFC programs (i.e. limited or universal purchase), and/or presence of school-based vaccine mandates were associated with adolescent vaccination levels.

METHODS

We performed a cross-sectional analysis of state-level associations between these policies and 2009 National Immunization Survey-TEEN vaccination rates for tetanus-containing, meningococcal conjugate (MCV4), and among females only, human papillomavirus (HPV) vaccines.

RESULTS

Medicaid reimbursement was not associated with vaccine coverage rates after adjusting for presence of vaccine-related school mandates, type of VFC program, proportion of adolescents attending preventive care visits, and state-specific distribution of insurance coverage. Participation in a more expansive VFC program (universal or universal-select) was significantly associated with HPV vaccine coverage, but not tetanus-containing vaccine or MCV4, among states that had mandates for any vaccines.

CONCLUSIONS

Our results suggest that, contrary to what has been shown for childhood vaccines, raising Medicaid reimbursement rates may not improve adolescent vaccine utilization. Instead, other policy changes may be more effective, such as expansion of VFC programs into universal purchase programs, further implementation of school-based vaccine mandates and efforts to raise preventive care visits among adolescents.

How parents' negative experiences at immunization visits affect child immunization status in a community in New York City

OBJECTIVE

Little is known about how families' experiences with immunization visits within the medical home may affect children's immunization status. We assessed the association between families' negative immunization experiences within the medical home and underimmunization.

METHODS

We surveyed parents (n = 392) of children aged 2-36 months about immunization experiences at community health centers, hospital-based clinics, private practices, and community-based organizations in New York City. We used Chi-square tests and odds ratios (ORs) to assess the relationship between medical home elements and parental immunization experience ratings. We used multivariable analysis to determine the association between negative experiences during immunization visits and underimmunization, controlling for insurance, maternal education, and receipt of benefits from the Special Supplemental Nutrition Program for Women, Infants, and Children.

RESULTS

The majority of children were of Latino race/ethnicity and had Medicaid and a medical home. One-sixth (16.9%) of families reported a previous negative immunization experience, primarily related to the child's reaction, waiting time, and attitudes of medical and office staff. Parents' negative immunization experiences were associated with the absence of four components of the medical home: continuity of care, family-centered care, compassionate care, and comprehensive care. In addition, children in families who reported a negative experience were more likely to have been underimmunized (adjusted OR = 2.00; 95% confidence interval 1.12, 3.58).

CONCLUSIONS

In a community in New York City, underimmunization of young children was associated with negative immunization experiences. Strategies to improve family experiences with immunization visits within the medical home (particularly around support for the family), medical and ancillary staff attitudes, and reduced waiting time may lead to improved immunization delivery.

Acceptance of pandemic 2009 influenza A (H1N1) vaccine in a minority population: determinants and potential points of intervention

OBJECTIVE

We sought to understand pandemic 2009 influenza A (H1N1) vaccine acceptance in a minority community including correlates of vaccine hesitancy and refusal. We identified intervention points to increase H1N1 vaccine coverage.

PATIENTS AND METHODS

Minority parents and caregivers of children ≤ 18 years participated in a cross-sectional survey. Statistical analyses included bivariate correlations, exploratory factor analyses, internal-consistency assessment, and logistic regressions.

RESULTS

The sample (N = 223) included mostly lower-income (71% [n = 159]) and black (66% [n = 147]) participants. Potential and actual receipt of pediatric H1N1 vaccination was low (36% [n = 80]). Pediatric H1N1 vaccine acceptance was associated with lack of insurance (odds ratio [OR]: 3.04 [95% confidence interval (CI): 1.26-7.37]), perceived H1NI pediatric susceptibility (OR: 1.66 [95% Cl: 1.41-1.95]), child vaccination prioritization in family (OR: 3.34 [95% CI: 1.33-8.38]), believing that H1N1 is a greater community concern than other diseases (OR: 1.77 [95% CI: 1.01-3.09]), believing that other methods of containment (eg, hand-washing, masks) are not as effective as the H1N1 vaccine (OR: 1.73 [95% CI: 1.06-2.83]), and a desire to promote influenza vaccination in the community (OR: 2.35 [95% CI: 1.53-3.61]).

CONCLUSIONS

We found low acceptance of the H1N1 vaccine in our study population. Perceived influenza susceptibility, concern about H1N1 disease, and confidence in vaccinations as preventive methods were associated with vaccine acceptance. Physician support for HIN1 vaccination will aid in increasing immunization coverage for this population, and health departments are perceived as ideal community locations for vaccine administration.

Psychosocial correlates of intention to receive an influenza vaccination among rural adolescents

The Centers for Disease Control and Prevention's Advisory Committee on Immunization Practices recently expanded annual influenza vaccination recommendations to include all children 6 months through 18 years of age. Adolescent attitudes toward influenza vaccination may play a key role in reaching this newly added age group. This study examined the association between attitudes toward influenza vaccination and intention to be vaccinated among rural adolescents. Data were collected from baseline surveys distributed to adolescents in September/October 2008, prior to the H1N1 influenza pandemic, in two counties participating in a school-based influenza vaccination intervention trial in rural Georgia (N = 337). Survey items were based on constructs from the Health Belief Model and the Integrated Behavioral Model. Approximately one-third of participants (33.8%) intended to receive an influenza vaccination, 33.5% did not intend to be vaccinated and 28.8% were unsure. Controlling for background factors, intention to receive an influenza vaccination was associated with low perceived barriers [odds ratio (OR) = 0.77, P < 0.001], injunctive norms (OR = 1.23, P = 0.002) and receipt of influenza vaccination in the past year (OR =6.21, P < 0.001). Findings suggest that perceived barriers and injunctive social norms may influence vaccination acceptance among rural adolescents. Future influenza vaccination efforts geared toward rural middle and high school students may benefit from addressing adolescent attitudes toward influenza vaccination.

Perception of barriers to immunization among parents of Hmong origin in California

OBJECTIVES

We explored factors associated with perception of barriers to immunization among parents of Hmong origin in California, whose children experience persistent immunization inequities even with health insurance.

METHODS

A partnership of academic researchers and members of the Hmong community conducted a community-based participatory research project. We collected data in naturalistic settings with a standardized instrument. We analyzed responses from 417 parents and caregivers and created a structural equation model to determine factors that contributed to perceived barriers.

RESULTS

Of 3 potential contributing factors to perceived barriers-nativity, socioeconomic position, and use of traditional Hmong health care (i.e., consulting shamans and herbalists)-the latter 2 significantly predicted higher perceived barriers to immunization. Nativity, indicated by years in the United States, age of arrival in the United States, and English language fluency, did not predict perceived barriers.

CONCLUSIONS

Interventions aimed at reducing immunization inequities should consider distinct sociocultural factors that affect immunization rates among different refugee and immigrant groups.

A stepped intervention increases well-child care and immunization rates in a disadvantaged population

OBJECTIVE

To test a stepped intervention of reminder/recall/case management to increase infant well-child visits and immunization rates.

METHODS

We conducted a randomized, controlled, practical, clinical trial with 811 infants born in an urban safety-net hospital and followed through 15 months of life. Step 1 (all infants) involved language-appropriate reminder postcards for every well-child visit. Step 2 (infants who missed an appointment or immunization) involved telephone reminders plus postcard and telephone recall. Step 3 (infants still behind on preventive care after steps 1 and 2) involved intensive case management and home visitation.

RESULTS

Infants in the intervention arm, compared with control infants, had significantly fewer days without immunization coverage in the first 15 months of life (109 vs 192 days P < .01) and were more likely to have >or=5 well-child visits (65% vs 47% P < .01). In multivariate analyses, infants in the intervention arm were more likely than control infants to be up to date with 12-month immunizations and to have had >or=5 well-child visits. The cost per child was $23.30 per month.

CONCLUSION

This stepped intervention of tracking and case management improved infant immunization status and receipt of preventive care in a population of high-risk urban infants of low socioeconomic status.

Adolescent vaccination: coverage achieved by ages 13-15 years, and vaccinations received as recommended during ages 11-12 years, National Health Interview Survey 1997-2003

PURPOSE

To present progress toward Healthy People 2010 vaccination objectives for adolescents aged 13-15 years, and to determine how much catch-up and routine vaccination was administered at the recommended ages of 11-12 years.

METHODS

Data from the 1997-2003 National Health Interview Survey were evaluated. In the first analysis, vaccination coverage levels for adolescents aged 13-15 years were determined for each survey year. Main outcome measures include the percent of adolescents who had received the three-dose hepatitis B vaccine (Hep B) series, the two-dose measles/mumps/rubella vaccine (MMR) series, the tetanus and diphtheria toxoids (Td) booster, and one dose of varicella vaccine. In the second analysis, data from all survey years were combined and vaccination dates were analyzed to determine the percentage of adolescents who were missing any vaccines at ages 11-12 and received them at that age. Data for varicella vaccine were sufficient only for the first analysis.

RESULTS

Among the approximately 15%-20% of respondents who reported vaccination history from records in the home and who were reporting on a 13-15-year-old, coverage with three doses of Hep B increased significantly during 1997-2001, from 15.2% to 55.0%. Coverage with MMR and Td fluctuated, with no significant increase; highs were 76.7% for MMR in 2003 and 36.2% for Td in 2002. Examination of vaccination dates for all surveyed adolescents showed that among 11-12-year-olds who needed catch-up vaccine, 0.6%-31.3% were brought up to date for Hep B and 22.1%-31.8% were brought up to date for MMR. For Td, 2.6%-15.4% of 11-12-year-olds who had not previously received Td received the vaccine.

CONCLUSION

Vaccination coverage among adolescents aged 13-15 years was below the Healthy People 2010 goals of 90%, but generally increased over the survey years. However, the suboptimal delivery of needed vaccines during ages 11 and 12 is concerning in light of recent vaccine recommendations targeted at this age. Continuing to focus on strategies to make adolescent preventive care, including vaccination, a new norm is essential.

The effect of lack of insurance, poverty and paediatrician supply on immunization rates among children 19-35 months of age in the United States

RATIONAL, AIMS AND OBJECTIVES

Previous studies found that the increasing number of paediatricians in the United States was associated with improved childhood immunization coverage, while the increasing poverty level and the lack of health insurance reduced access to health care. We evaluated whether changes in the number of paediatricians, poverty level and health insurance affected national childhood immunization coverage in the state levels of the United States.

METHODS

Data were collected primarily from the US National Immunization Surveys, series 4:3:1:3:3 from years 1995 and 2003. Ordinal logistic regression analysis was used to analyse the relationships among variables.

RESULTS

Over 8 years studied, immunization coverage increased for children aged 19-35 months from 52.3% to 79.8% in the 50 states. The average number of paediatricians per 1000 births increased 28.7% while the percentage of children without health insurance declined 15.6%, and the percentage of children who lived in poverty level declined 17.3%. In 1995, the states with higher immunization coverage were associated with higher numbers of paediatricians [odds ratio (OR), 32.73; 95% confidence interval (CI), 5.96-179.77]. In 2003, the higher numbers of paediatricians still played a role in the increased immunization coverage (OR, 4.69; 95% CI, 1.01-21.78); however, the higher rate of uninsured children in 2003 had an even greater effect upon immunization coverage. Compared with states with lower rates of uninsured children, states with intermediate and higher rates of uninsured children had sixfold (OR, 0.16; 95% CI, 0.03-0.81) and 16-fold (OR, 0.06; 95% CI, 0.01-0.40) decreased childhood immunization coverage, respectively.

CONCLUSION

Between 1995 and 2003 in the United States, the lack of health insurance became more prominent than the supply of paediatricians in affecting immunization coverage for children aged 19-35 months. Future improvements in insurance coverage for children will likely lead to greater immunization coverage.

Vaccination coverage by special health care needs status in young children

OBJECTIVE

The purpose of this study was to compare vaccination coverage among children 19 to 35 months of age with and without special health care needs overall and among demographic subgroups.

METHODS

Data are from the National Survey of Children With Special Health Care Needs, a module of the State and Local Area Integrated Telephone Survey, which was sponsored by the Health Resources and Services Administration Maternal and Child Health Bureau and conducted in 2000-2002 by the Centers for Disease Control and Prevention National Center for Health Statistics. We used data from the National Immunization Survey and the National Survey of Children With Special Health Care Needs to examine immunization coverage rates for individual vaccines and an array of combined series vaccinations. The relationship between special needs and immunization status was analyzed by age, gender, and race or ethnicity of the child; the child's health insurance type; the mother's educational attainment and presence in the household; and household income relative to the federal poverty level.

RESULTS

Overall, there were no significant differences between children with and without special needs for any of the individual antigens or combined immunization series. Some significant differences by special needs status were found within certain demographic subgroups.

CONCLUSIONS

Our results suggest that, generally children with special health care needs have immunization rates that are very similar to typically developing children. There is some evidence that children with special health care needs are at risk for underimmunization if they are non-Hispanic white or live in an affluent household and are more likely to be immunized if they are Hispanic, poor, publicly insured, or if their mothers did not complete high school. These findings may be due to outreach or support programs that target disadvantaged children. However, it is important to note that the majority of comparisons within demographic subgroups show no significant differences between children with special health care needs and children without special health care needs.

Vaccination coverage estimates for selected counties: achievement of Healthy People 2010 goals and association with indices of access to care, economic conditions, and demographic composition

OBJECTIVES

We provided vaccination coverage estimates for 181 counties; evaluated the extent to which Healthy People 2010 (HP 2010) vaccination coverage objectives were achieved; and examined how variations in those estimates depend on access to care and economic conditions.

METHODS

We analyzed data for 24,031 children aged 19 to 35 months sampled from the 2004 and 2005 National Immunization Survey.

RESULTS

Children living in the 181 counties represented 49% of all the 19- to 35-month-old children living in the U.S. None of the 181 counties had coverage for the polio, measles-mumps-rubella, Haemophilus influenzae type B, and hepatitis B vaccines that was significantly lower than the HP 2010 objective of 90% coverage. However, as many as 30.4% of the counties did not achieve the HP 2010 objective for diphtheria, tetanus toxoids, and acellular pertussis or diphtheria and tetanus toxoids and pertussis (DtaP/DTP), and as many as 6.6% did not achieve the goal for varicella (VAR). If children who received three doses of DTaP/DTP had received a final fourth dose, and if all children had received one dose of VAR, all of the 181 counties would have achieved the HP 2010 vaccination coverage target of 80% for the entire 4:3:1:3:3:1 vaccination series. Factors found to be associated with low county-level vaccination coverage rates were correlates of poverty, and factors found to be associated with high county-level vaccination coverage rates were correlates of access to pediatric services.

CONCLUSIONS

HP 2010 vaccination coverage goals for all 181 counties can be achieved by improving vaccination coverage for only two vaccines. Those goals may be achieved most efficiently by targeting interventions in counties where indices of poverty are high or where access to pediatric services is low.

Childhood immunization coverage by provider type

OBJECTIVE

To determine how child characteristics and immunization coverage levels differ among children using public and private providers.

METHODS

Immunization coverage rates between 1996 and 2004 were compared among children aged 19-35 months, using data from the National Immunization Survey. Coverage was based on the 4:3:1:3:3 vaccine series: four or more doses of diphtheria, tetanus toxoids, acellular pertussis vaccine; three or more doses of poliovirus vaccine; one or more doses of measles-mumps-rubella vaccine; three or more doses of Haemophilus influenzae type b vaccine; and three or more doses of hepatitis B vaccine. Coverage differences were examined by provider types (child vaccinated by private, public, or a mix of providers), and stratified by child's race/ethnicity, area of residence, and household income level.

RESULTS

Between 1996 and 2004, the proportion of children seeing exclusively private providers increased (58%-61%; P < .05); the proportion seeing only public providers decreased (19%-15%; P < .01). Coverage levels increased among children seeing all provider types. Coverage levels were higher for children using private providers than those using public providers in 2004 (83% vs 79%; P <.05). Except for White race (coverage was higher among those using private providers vs public providers), coverage levels by demographic variables did not significantly differ between children using only public or only private providers in 2004.

CONCLUSIONS

Equal emphasis should be placed on the efforts of public providers and private providers to increase coverage among children of all race/ethnicity, income, and residential groups.

Taking a closer look: an examination of measles, mumps, and rubella immunization uptake in Saskatoon

BACKGROUND

Immunization is one of the most successful public health initiatives in Canada, yet continuous monitoring of coverage rates is essential to ensure high uptake for sustained success. The purpose of this study was to utilize newly available data from the Saskatchewan Immunization Management System (SIMS) to examine city and neighbourhood uptake of the Measles, Mumps and Rubella vaccine and identify potential factors that contribute to low immunization uptake in Saskatoon.

METHODS

The study examined records for 10,287 two year olds between 1999 and 2002 using an ecological study design. The first step consisted of simple rate calculations to determine the total, complete, up-to-date and not up-to-date immunization rates for the city of Saskatoon and in each residential neighbourhood. Quantitative neighbourhood-level data were then used to determine if neighbourhood variables could significantly contribute to the variation in immunization coverage.

RESULTS

The findings revealed MMR/MR immunization rates were relatively stable between 1999 and 2002. However, significant disparities were found at the neighbourhood level, with areas of social and economic disadvantage having lower rates of total, complete, and up-to-date immunization uptake compared to areas of greater social and economic wealth. Multivariate linear regression revealed 80.6% of variation in up-to-date immunization uptake in Saskatoon could be explained by the proportion of single mothers and vehicles per capita in the neighbourhood.

CONCLUSION

Significant inequities in immunization uptake exist on the neighbourhood level in Saskatoon. These findings are supported by the literature and may indicate the presence of real or perceived barriers to immunization in some Saskatoon neighbourhoods.

Postpartum mothers' attitudes, knowledge, and trust regarding vaccination

OBJECTIVE

To examine attitudes and knowledge about vaccinations in postpartum mothers.

METHODS

This cross-sectional study collected data via written survey to postpartum mothers in a large teaching hospital in Connecticut. We used multivariable analysis to identify mothers who were less trusting with regard to vaccines.

RESULTS

Of 228 mothers who participated in the study, 29% of mothers worried about vaccinating their infants: 23% were worried the vaccines would not work, 11% were worried the doctor would give the wrong vaccine, and 8% worried that "they" are experimenting when they give vaccines. Mothers reported that the most important reasons to vaccinate were to prevent disease in the baby (74%) and in society (11%). Knowledge about vaccination was poor; e.g., 33% correctly matched chicken pox with varicella vaccine. Mothers who were planning to breastfeed (P=.01), were primiparous (P=.01), or had an income<$40,000 but did not receive support from the women, infants, and children (WIC) program were less trusting with regard to vaccines (P=.03). Although 70% wanted information about vaccines during pregnancy, only 18% reported receiving such information during prenatal care.

CONCLUSION

Although the majority of infants receive vaccines, their mothers have concerns and would like to receive immunization information earlier. Mothers who are primiparous, have low family incomes but do not qualify for the WIC program, or are breastfeeding may need special attention to develop a trusting relationship around vaccination. Mothers would benefit from additional knowledge regarding the risks and benefits of vaccines particularly during prenatal care.

Identifying risk factors for underimmunization by using geocoding matched to census tracts: a statewide assessment of children in Hawaii

OBJECTIVE

Obtaining childhood immunization coverage data for small geographic areas is difficult and resource-intensive, especially in the absence of comprehensive immunization registries. To identify factors that are associated with delayed immunization, we collected school-entry immunization records statewide and used geocoding to link to publicly available census tract sociodemographic data.

METHODS

Immunization records were reviewed for children who were enrolled in all public and private school kindergarten programs in Hawaii in the 2002-2003 school year; immunization status at the time of the second birthday was determined. The main outcome variable was up-to-date status for the 4:3:1:3:3 vaccination series (4 doses of diphtheria-tetanus-pertussis, 3 doses of polio, 1 dose of measles-mumps-rubella, 3 doses of Haemophilus influenzae type b, and 3 doses of hepatitis B vaccines). Children's home addresses were geocoded to census tracts; coverage rates by tract were mapped, and sociodemographic data from Census 2000 files were used to identify factors that were associated with delays in immunization.

RESULTS

Records were obtained for 15,275 of 15,594 children registered in Hawaii kindergartens. Overall, 78% had completed their 4:3:1:3:3 series by their second birthday. Risk factors for delayed immunization included delayed immunization at 3 months of age, living in Maui County, living in a neighborhood where a low proportion of adults had postsecondary education, and living in a neighborhood where a high proportion of households spoke a language other than English at home. The majority (80%) of underimmunized children would have required only 1 additional visit to bring them up-to-date.

CONCLUSIONS

Retrospective review of kindergarten-entry immunization data revealed geographic areas with lower immunization coverage, and geocoding to census tracts identified associated sociodemographic risk factors. This is a practical method for state or city health departments to identify pockets of need and to direct resources appropriately.

Additional health care visits needed among adolescents for human papillomavirus vaccine delivery within medical homes: a national study

OBJECTIVE

We estimated the additional number of primary care visits needed to deliver 3 doses of human papillomavirus vaccine to all US adolescents in medical homes. We determined adolescent and family factors associated with needing the greatest number of additional visits for full human papillomavirus vaccination.

METHODS

We performed a cross-sectional analysis of adolescents 11 to 21 years of age included in the 2002 and 2003 Medical Expenditure Panel Surveys (n = 2900) to measure existing primary care visits to pediatricians, family physicians, obstetrician/gynecologists, and internists. We then estimated additional visits needed for human papillomavirus vaccination. We determined the number of additional visits needed within a 6-, 12-, 18-, or 24-month vaccination window.

RESULTS

Within a 12-month period, 72% of female adolescents would need 3 visits for human papillomavirus vaccination if the vaccine was introduced at a preventive visit; 9% and 16% would need 1 and 2 more visits, respectively. Similarly, 79% of male patients would need 3 visits; 7% and 12% would need 1 and 2 more visits, respectively. If all opportunities to vaccinate were used, then 41% of female patients and 52% of male patients would need 3 additional visits within 12 months. With expansion of the window to 24 months and vaccination at every possible visit, 23% of female patients and 37% of male patients would need 3 additional visits. Factors that predicted needing more visits (2 or 3 vs 0 or 1 in 24 months) included being older, male, black, Hispanic, uninsured, and near-poor.

CONCLUSIONS

Most adolescents would require 2 or 3 additional primary care visits to receive 3 vaccines for human papillomavirus in the medical home. Strategies to minimize additional visits include vaccinating patients at all primary care visits and encouraging annual preventive visits.

Simple solutions to complex issues: minimizing disparities in childhood immunization rates by providing walk-in shot clinic access

The aims of this project were to minimize organizational barriers and increase access to immunizations for children aged 6 months to 21 years in a multiethnic community health center in Honolulu. The intervention consisted of opening a "walk-in" shot clinic (WISC), run by a nurse practitioner, 2 evenings per week and Saturdays. Between January and July 2005, 351 clients accessed the clinic, with 774 immunizations administered. Clinic satisfaction measures were excellent. Up-to-date immunization status for all clients improved significantly. The WISC is an effective and customer-friendly way to improve childhood and adolescent immunization rates in a community health center setting.

Immunization coverage and its determinants in children aged 12–23 months in Gansu, China

The study aimed to assess the determinants of immunization coverage in 12-23-month-old children born in 1997 and living in Gansu Province in West China. The World Health Organization's cluster sampling technique was used. Information was gathered by face-to-face interviews with caregivers and from immunization records. Bacille Calmette Guerin (BCG), Polio and Diphtheria, Tetanus, Pertussis (DTP) coverage at 3 months was 51.2%. At 8 and 12 months, including the Measles Vaccine, coverage was 71.3 and 86.0%, respectively. The variables associated with delay at 12 months were: low socio-economic level, low number of sources of information on vaccination and delayed immunization at 3 months. Improved immunization coverage could be achieved by improving access and delivery to poor and remote areas and by awarding incentives to providers at primary care level.

Influenza vaccination coverage of children aged 6 to 23 months: the 2002-2003 and 2003-2004 influenza seasons

BACKGROUND

Beginning in 2002 the Advisory Committee on Immunization Practices encouraged, when feasible, annual influenza vaccination of all children aged 6 to 23 months and household contacts and out-of-home caregivers of children < 2 years of age.

OBJECTIVE

We sought to report influenza vaccination coverage for the 2002-2003 and 2003-2004 influenza seasons among children aged 6 to 23 months according to demographic and immunization-provider characteristics.

METHODS

Data from the 2003 and 2004 National Immunization Survey were analyzed. Two measures of childhood influenza vaccination are reported: receipt of > or = 1 influenza vaccination and full vaccination (ie, receipt of the appropriate number of doses on the basis of previous vaccination history). chi2 tests and logistic-regression analyses to test for associations between influenza vaccination status and demographic characteristics were performed.

RESULTS

In the 2002-2003 and 2003-2004 influenza seasons only 7.4% and 17.5%, respectively, of children aged 6 to 23 months received > or = 1 influenza vaccination, whereas only 4.4% and 8.4%, respectively, were fully vaccinated. In both seasons, adjusted influenza vaccination coverage was significantly lower among children living below the poverty level; non-Hispanic black children; older children; children with less-educated mothers; children vaccinated only at public clinics; and children not residing in a metropolitan statistical area.

CONCLUSION

During the first 2 years of the Advisory Committee on Immunization Practices' encouragement for children aged 6 to 23 months to receive influenza vaccination, coverage was low, with significant demographic differences in receipt of vaccination. Beginning with the 2004-2005 influenza season, they replaced the encouragement with a recommendation that children aged 6 to 23 months receive annual influenza vaccination. Substantial work remains to fully and equitably implement this new recommendation and ensure vaccination with 2 doses for previously unvaccinated children.

Impact of state vaccine financing policy on uptake of heptavalent pneumococcal conjugate vaccine

OBJECTIVE

We examined heptavalent pneumococcal conjugate vaccine (PCV7) uptake among children aged 19 to 35 months in the United States and determined how uptake rates differed by state vaccine financing policy.

METHODS

We analyzed data from the 2001-2003 National Immunization Survey. States that changed their vaccine financing policy between 2001 and 2003 (n=17) were excluded from analysis. Logistic regression was performed to identify the association between state vaccine financing policy and receipt of 3 or more doses of PCV7 after control for demographic characteristics.

RESULTS

The proportion of children receiving 3 or more doses increased from 6.7% in 2001 to 69.0% in 2003. After controlling for demographic characteristics, children residing in states that provided all vaccines except PCV7 to all children had lower odds of receiving 3 or more doses compared to children residing in states that provided PCV7 only to children eligible for the Vaccines for Children program (odds ratio=0.58; 95% confidence interval=0.51, 0.66).

CONCLUSION

It is essential that we continue to monitor the effect that state vaccine financing policy has on the delivery of PCV7 and future vaccines, which are likely to be increasingly expensive.

Measles immunization coverage determined by serology and immunization record from children in two Chicago communities

OBJECTIVES

We compared the prevalence of measles immunization determined by serology with the prevalence of measles immunization determined by immunization records, and identified factors predictive of measles immunization among a sample of children from two Chicago communities.

METHODS

We collected demographic information and blood specimens from a sample of children aged 12-71 months in two Chicago communities at risk for low measles immunization coverage levels. We collected immunization information from provider records, parent-held records, and the statewide immunization registry. We compared evidence of immunization determined by serology with evidence of immunization from these three sources of immunization records.

RESULTS

The sample of children from the two communities had serologic measles immunity levels of 85% and 90%. Significantly fewer children had evidence of immunization by record in both communities (45% and 63%, respectively).

CONCLUSIONS

Immunization coverage levels determined using immunization records were significantly lower than immunization coverage determined using serology. A fully populated immunization registry used by all immunization providers could prevent the problems of record loss and scatter.

Uptake of varicella vaccination among young children in the United States: a success story in eliminating racial and ethnic disparities

OBJECTIVE

To examine uptake of varicella vaccine, a live attenuated vaccine licensed in 1995 and recommended in 1996 for routine vaccination of US children 12 to 18 months of age.

METHODS

Data were for 178,616 children (19-35 months of age) and were collected in the 1997 to 2004 National Immunization Survey. The main outcome measures were estimated varicella vaccine coverage from 1997 to 2004, coverage among susceptible children (ie, those without a history of varicella disease), racial/ethnic disparities, risk factors for nonvaccination, missed opportunities to vaccinate simultaneously with other recommended vaccines, and projected increases in coverage after elimination of missed opportunities for simultaneous vaccination.

RESULTS

Varicella vaccine coverage rates increased from 26% in 1997 to 87% in 2004. State-specific coverage rates increased 44 to 80 percentage points and were >80% in 42 states and >90% in 13 states by 2004. Coverage among susceptible children increased from 62% in 1999 to 88% in 2004. From 1998 onward, no statistically significant differences in coverage were found between white and black children, whereas Hispanic children had higher coverage rates than white children in 1998 to 2001 and 2004. Risk factors for undervaccination included living in the Midwest region, living in a household with >1 child, living in nonmetropolitan areas, living below the poverty level, having a mother who did not have a college degree, and having public providers. If missed opportunities for simultaneous vaccination had been eliminated, then coverage rates would have increased from 58% to 94% in 1999 and from 87% to 96% in 2004.

CONCLUSIONS

Uptake of varicella vaccine has been steady and is an example of successful elimination of racial and ethnic disparities. Additional focus should be placed on reducing missed opportunities for simultaneous vaccination, improving coverage in rural areas and the Midwest region, and closing remaining gaps related to maternal education, provider type, and multiple-children households.

Measurement of vaccination coverage at age 24 and 19-35 months: a case study of multiple imputation in public health

Aim

Childhood immunization coverage in the United States (U.S.) is often measured at age 24 months or, in the National Immunization Survey (NIS) at age of interview, which is between 19 and 35 months. This paper compares these standards.

Methods

Data from the NIS is used to compare immunization coverage at time of interview, retrospectively among all children aged 24 or more months at time of interview, and obtained via multiple imputation (with 10 imputations) for all children, both nationally, by state, and by demographic groups.

Results

At the national level, the difference between the 19–35 month estimate and the 24 month complete-case estimate was 1.9 percentage points. For most but not all states and subgroups, the 19–35 month estimate was higher than the 24 month complete-case estimate. The difference between vaccination coverage measured at 19–35 months and 24 months ranged from -2.3 to 7.5 percentage points among states. For three states, the difference between the 19–35 month and 24 month complete-case estimate was more than 6 percentage points, in twelve states there was a 4–6 percentage point difference, and in sixteen states a 2–4 percentage point difference. Conversely, five states had higher 24 month complete-case estimates than 19–35 month estimates.

Conclusion

We found that the coverages at 19–35 and 24 months differ such that they would rarely be adequate surrogates for one another, particularly at a state level. Multiple imputation, which is easily implemented, increases precision of estimates of coverage at age 24 months.

Reducing Disparities in Vaccination Rates Between Different Racial/Ethnic and Socioeconomic Groups

There are well-documented disparities in vaccination rates between different socioeconomic and racial/ethnic groups in the United States. These disparities persist in spite of an overall increase in vaccination rates during the last decade and the implementation of several interventions that have aimed to increase vaccination rates in disadvantaged groups. Although many interventions are efficacious at improving vaccination rates under trial conditions, these interventions when extended to the general population frequently do not appreciably improve its health. Explanations for this limited intervention efficiency include poor adherence to protocols in real life versus idealized trial situations, changes in baseline so that the trial conditions are no longer replicable, and the contribution of other community-level factors that make it difficult to extend the trial methods to other communities. Multilevel community intervention trials recognize and address the multiple competing forces that shape the health of the population in cities and have the potential to increase vaccination rates among minorities and marginalized groups.

Children who have received no vaccines: who are they and where do they live?

CONTEXT

Each year 2.1 million children 19 to 35 months of age are undervaccinated. Among these are children who have received no vaccinations. Unvaccinated children are at increased risk of acquiring and transmitting vaccine-preventable diseases.

OBJECTIVES

To assess whether the characteristics of children with no vaccinations differ from those of undervaccinated children, to monitor trends in the numbers of unvaccinated children, and to identify states with high rates and counties with large numbers of unvaccinated children.

DESIGN

A nationally representative probability sample of children 19 to 35 months of age was collected annually between 1995 and 2001. Vaccination histories were ascertained from children's medical providers. Undervaccinated children had received > or =1 dose of diphtheria-tetanus-pertussis, polio, measles, Haemophilus influenzae type b, hepatitis B, or varicella vaccine but were not fully vaccinated. Unvaccinated children were children who were reported as having no medical providers and having received no vaccinations or children whose medical providers reported administering no vaccinations.

PARTICIPANTS

A total of 151,720 children sampled between 1995 and 2001, 795 of whom were unvaccinated.

RESULTS

Undervaccinated children tended to be black, to have a younger mother who was not married and did not have a college degree, to live in a household near the poverty level, and to live in a central city. Unvaccinated children tended to be white, to have a mother who was married and had a college degree, to live in a household with an annual income exceeding 75,000 dollars, and to have parents who expressed concerns regarding the safety of vaccines and indicated that medical doctors have little influence over vaccination decisions for their children. Unvaccinated children were more likely to be male than female. Annually, approximately 17,000 children were unvaccinated. The largest numbers of unvaccinated children lived in counties in California, Illinois, New York, Washington, Pennsylvania, Texas, Oklahoma, Colorado, Utah, and Michigan. States that allowed philosophical exemptions to laws mandating vaccinations for children as they entered school had significantly higher estimated rates of unvaccinated children.

CONCLUSIONS

Unvaccinated children have characteristics that are distinctly different from those of undervaccinated children. Unvaccinated children are clustered geographically, increasing the risk of transmitting vaccine-preventable diseases to both unvaccinated and undervaccinated children.