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

Worth a Shot: Experience and Lessons From an Unsuccessful Pediatric Immunization Quality Improvement Effort in a Large Health System During the COVID-19 Pandemic

INTRODUCTION

During the coronavirus disease of 2019 (COVID-19) pandemic, routine childhood immunization rates dropped dramatically across the world, and the Military Health System (MHS) was no exception. In the MHS, which is a large, universally covered, low-to-no-cost health system, the immunization rates with the measles, mumps, and rubella (MMR) vaccine remain below the rate necessary to prevent community transmission of measles. We aimed to improve childhood immunization rates in the MHS with an expansive quality improvement project.

MATERIALS AND METHODS

Measles, mumps, and rubella immunization rates served as proxy outcome measures for routine immunization rates tracked by the Center for Disease Control multi-immunization combination measures. The tracked measure was the percentage of 16- to 18-month olds and 6-year olds who had received MMR #1 and MMR #2, respectively. Various countermeasures were implemented throughout the study period, and standard quality improvement analyses informed the effect of countermeasures.

RESULTS

By January 2023, the percentage of 16- to 18-month olds and 6-year olds who had received MMR #1 and MMR #2 was 85% and 91%, respectively, with no positive shift in immunization rates despite various countermeasures introduced during the study period. For reference, the MMR immunization rates of commercial health maintenance organization and commercial preferred provider organization for 24-month-old populations were 92% and 90.3%, respectively. On chart review, the most common cause for under-immunization (55%) was vaccine abandonment. MMR #1 rates rose to 92% in 24-month olds.

CONCLUSIONS

Measles, mumps, and rubella immunization rates within the MHS remained below commercial health system rates and below public health standards required for herd immunity despite various countermeasures throughout the COVID-19 pandemic. Immunization rates increased with age, suggesting that children within the MHS eventually catch up despite potential barriers.

Newborn medication adherence and childhood under-immunization in military beneficiaries

BACKGROUND

The American Academy of Pediatrics recommends birth doses of vitamin K, erythromycin ointment, and the hepatitis B vaccine, but the relationship between birth medication administration and childhood immunization compliance is understudied. The objective of this study is to evaluate rates of newborn medication administration, and risk factors for refusal in military beneficiaries and determine the relationship between medication refusal and under-immunization at 15 months.

METHODS

A retrospective chart review was completed for all term and late preterm infants born at Brooke Army Medical Center, San Antonio, TX, from January 1, 2016, to December 31, 2019. The electronic medical record was queried for birth medication administration, maternal age, active-duty status, rank, and birth order. Childhood immunization records were extracted for all patients who continued care at our facility. A patient was considered completely immunized if they had received at least 22 vaccines by 15 months: three doses of the hepatitis B vaccine [Pediarix^TM], two doses of the rotavirus vaccine [Rotarix^TM], four doses of the DTAP vaccine [Pediarix^TM and Acel-Immune^TM], three doses of Haemophilus influenza B vaccine [Pedvaxhib^TM], four doses of pneumococcal [Prevnar 13^TM], three doses of IPV [Pediarix^TM], one dose of measles, mumps, and rubella [MMR^TM], one dose of varicella [Varivax^TM] and one dose of hepatitis A vaccine [Harvix^TM].

RESULTS

Seven thousand one hundred and forty infants were included; 99.3% received vitamin K, 98.8% received erythromycin ointment, and 93.8% received the hepatitis B vaccine. Refusal of the erythromycin ointment and hepatitis B vaccine was associated with older maternal age and higher birth order. Childhood immunization records were available for 607 infants; 7.2% (n = 44) were under-immunized by 15 months, with no infants being non-immunized. Refusal of the hepatitis B vaccine (RR: 2.9 (CI 1.16-7.31)) only at birth was associated with a higher risk of being under-immunized.

CONCLUSIONS

Refusal of the hepatitis B vaccine in the nursery is associated with a risk of being under-immunized in childhood. Obstetric and pediatric providers should be aware of this association for appropriate family counseling.

Analysis of State-Specific Differences in Childhood Vaccination Coverage in Rural India

There is little research on state-level differences in child health outcomes in India. The aim of this study was to identify state-level characteristics that relate to childhood immunizations. Most state-level characteristics came from the 2011 Indian Census. Individual-level data and other state-level characteristics were obtained from the 2007⁻2008 District Level Household and Facility Survey. Predictors of full vaccination were assessed with logistic regression models. Among 86,882 children 12⁻36 months, 53.2% were fully vaccinated. Children living in bigger households (≥7 members), born in non-institutional settings, and female had lower odds of complete vaccination. Individuals living in states in the mid-range of poverty had lower odds of full vaccination compared to those in lower or higher poverty states (3rd vs. 1st quintile: odds ratio [OR]: 0.36, 95% confidence interval [CI]: 0.30, 0.42). Greater average population per primary health center was associated with decreased odds of full vaccination (5th vs. 1st quintile: OR: 0.37, 95% CI: 0.30, 0.47). Vaccination coverage in India can be explained by a complex interplay of individual- and state-level factors. Solutions to increasing vaccination must be multisectoral and acknowledge the cultural and socio-economic diversity that influences an individual child's vaccination coverage along with within-state disparities.

Neighbourhood influence on the fourth dose of diphtheria-tetanus-pertussis vaccination

OBJECTIVES

Using 542,159 vaccination records from children born between April 1, 2007, and March 31, 2012, in the Michigan Care Improvement Registry and data from the American Community Survey, we determine if neighbourhood-level characteristics at the Census tract level and block level are associated with low uptake of the fourth dose of diphtheria-tetanus-acellular pertussis vaccine (DTaP4).

STUDY DESIGN

This study was a cross-sectional study.

METHODS

We used exploratory factor analysis to determine important socio-economic factors at the Census block level and tract level. We then used generalised estimating equations to test the relationship between block- and tract-level socio-economic factors and DTaP4 uptake.

RESULTS

DTaP4 coverage was 88.6% (95% confidence interval [CI]: 88.4%-88.7%) in Michigan. At the Census tract level, two factors surfaced as important for DTaP4 vaccination: 'affluence' (Cronbach's alpha = 0.88) and 'socio-economic disadvantage' (Cronbach's alpha = 0.89). At the Census block level, one factor was important: 'affluence' (Cronbach's alpha = 0.90). Affluence may relate to knowledge about medical exemptions and antivaccination sentiment, while socio-economic disadvantage may indicate limited access to healthcare resources. Children in high-affluence tracts had 1.08% lower vaccination coverage (95% CI: -1.62% to -0.55%) than children in low affluence tracts. Children in low socio-economic disadvantage tracts had 2.92% higher coverage than children in high socio-economic disadvantage tracts (95% CI: 2.58%-3.26%).

CONCLUSIONS

This study articulates the need to further understand the contribution of neighbourhood-level characteristics, from both affluent and socioeconomically disadvantaged areas to low vaccination rates. Developing a better understanding of these social environmental factors will help determine useful community-level interventions to improve vaccination rates and reduce disease burden.

Socioeconomic Background and Commercial Health Plan Spending

BACKGROUND

Risk-adjustment algorithms typically incorporate demographic and clinical variables to equalize compensation to insurers for enrollees who vary in expected cost, but including information about enrollees' socioeconomic background is controversial.

METHODS

We studied 1 182 847 continuously insured 0 to 19-year-olds using 2008-2012 Blue Cross Blue Shield of Massachusetts and American Community Survey data. We characterized enrollees' socioeconomic background using the validated area-based socioeconomic measure and calculated annual plan payments using paid claims. We evaluated the relationship between annual plan payments and geocoded socioeconomic background using generalized estimating equations (γ distribution and log link). We expressed outcomes as the percentage difference in spending and utilization between enrollees with high and low socioeconomic backgrounds.

RESULTS

Geocoded socioeconomic background had a significant, positive association with annual plan payments after applying standard adjusters. Every 1 SD increase in socioeconomic background was associated with a 7.8% (95% confidence interval, 7.2% to 8.3%; P < .001) increase in spending. High socioeconomic background enrollees used higher-priced outpatient and pharmacy services more frequently than their counterparts from low socioeconomic backgrounds (eg, 25% more outpatient encounters annually; 8% higher price per encounter; P < .001), which outweighed greater emergency department spending among low socioeconomic background enrollees.

CONCLUSIONS

Higher socioeconomic background is associated with greater levels of pediatric health care spending in commercially insured children. Including socioeconomic information in risk-adjustment algorithms may address concerns about adverse selection from an economic perspective, but it would direct funds away from those caring for children and adolescents from lower socioeconomic backgrounds who are at greater risk of poor health.

Relationship between receipt of substitutable for-fee vaccines and completion of the expanded programme on immunisation: a cross-sectional study in Fujian, China

OBJECTIVE

The aim of this study was to evaluate the relationship between receipt of the substitutable-for-fee vaccines (SFV) and completion of the expanded programme on immunisation (EPI).

DESIGN AND SETTINGS

A cross-sectional study was conducted in Fujian province, China.

PARTICIPANTS

Children who were born from 1 September 2009 to 31 August 2011, and who had been residing in the township for at least 3 months, were randomly recruited from 34 townships.

MAIN OUTCOMES MEASURES

Outcomes were completion rate of the EPI and coverage rate of the SFV.

RESULTS

The study included 1428 children, of whom 1350 (94.5%) finished the EPI and 282 (19.7%) received at least one dose of the SFV. Administration of the SFV was associated with an increased likelihood of completing the EPI (OR=3.2, 95% CI 1.3 to 7.6 in the total sample and OR=4.0, 95% CI 1.7 to 9.6 in the subsample of children in regions with the SFV accessibility). The impact of the SFV administration on completion of the EPI was larger among children whose parents have junior school education or less (97.8% and 97.9% vs 92.5% and 91.9%, both p<0.001) and among those with a timely hepatitis B vaccine first dose (98.5% vs 94.0%, p<0.001).

CONCLUSIONS

Receipt of SFV is associated with increased likelihood of completion of the EPI in Fujian, China.

On-time Measles and Pneumococcal Vaccination of Shanghai Children: The Impact of Individual-level and Neighborhood-level Factors

BACKGROUND

Measles-containing vaccines (MCVs) and pneumococcal conjugate vaccines (PCVs) can prevent a large proportion of infant deaths and are recommended by international organizations for inclusion in pediatric immunization schedules. In China, MCV but not PCV is publically funded and access to vaccination may be limited among nonlocals, who are rural migrants to cities. In this study, we estimate the proportion of Shanghai children with on-time MCV and PCV administration, compare vaccination in nonlocals versus locals and assess the impact of township-level characteristics on vaccination outcomes.

METHODS

Data from children in the Shanghai Immunization Program Information System were linked to township-level data from the 2010 China Census. We used generalized estimating equations with logistic regression models to assess the impact of residency and township-level predictors on on-time MCV and PCV administration.

RESULTS

Nonlocals had lower vaccination levels than locals. Compared with locals, nonlocals had 0.50 times the odds of MCV dose 1 by 9 months [95% confidence interval (CI): 0.47, 0.53], 0.42 times the odds of MCV dose 2 by 24 months (95% CI: 0.39, 0.45), 0.37 times the odds of PCV by 9 months of age (95% CI: 0.33, 0.42) and 0.41 times the odds of PCV by 24 months of age (95% CI: 0.37, 0.45). Overall, children had less on-time MCV and PCV administration in nonlocal-majority than local-majority townships.

CONCLUSIONS

Late vaccination negatively impacts disease control efforts in Shanghai. Nonlocals, particularly those living in nonlocal-majority townships, should especially be targeted for vaccination in order to improve disease control efforts in Shanghai.

Characterization of Heterogeneity in Childhood Immunization Coverage in Central Florida Using Immunization Registry Data

Despite high vaccine coverage in the United States in general, and in the State of Florida specifically, some children miss scheduled vaccines due to health system failures or vaccine refusal by their parents. Recent experiences with outbreaks in the United States suggest that geographic clustering of un(der)vaccinated populations represent a threat to the elimination status of some vaccine-preventable diseases. Immunization registries continue to expand and play an important role in efforts to track vaccine coverage and use. Using nearly 700,000 de-identified immunization records from the Florida Department of Health immunization information system (Florida SHOTS™) for children born during 2003-2014, we explored heterogeneity and potential clustering of un(der)vaccinated children in six counties in central Florida-Brevard, Lake, Orange, Oseola, Polk, and Seminole-that represent a high-risk area for importation due to family tourist attractions in the area. By zip code, we mapped the population density, the percent of children with religious exemptions, the percent of children on track or overdue for each vaccine series without and with exemptions, and the numbers of children with no recorded dose of each vaccine. Overall, we found some heterogeneity in coverage among the counties and zip codes, but relatively consistent and high coverage. We found that some children with an exemption in the system received the vaccines we analyzed, but exemption represents a clear risk factor for un(der)immunization. We identified many challenges associated with using immunization registry data for spatial analysis and potential opportunities to improve registries to better support future analyses.

Area-Level Socioeconomic Factors Are Associated With Noncompletion of Pediatric Preventive Services

We examined 4872 infants born consecutively, 2011-2012, and seen at 3 primary care centers to determine whether area-based socioeconomic measures were associated with noncompletion of common preventive services within the first 15 months. Addresses were geocoded and linked to census tract poverty, adult educational attainment, and household vehicle ownership rates. The quartile of patients in the highest poverty (adjusted odds ratio [aOR] 1.25; 95% confidence interval [CI] 1.01-1.54) and lowest vehicle ownership tracts (aOR 1.32; 95% CI 1.07-1.63) had significantly increased odds of service noncompletion. There were significant spatial clusters of low completion in Cincinnati's urban core. These findings have implications for preventive service delivery.

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.

Socio Cultural and Geographical Determinants of Child Immunisation in Borno State, Nigeria

Immunisation has been an important strategy for disease prevention globally. Despite proven successes in other settings, child immunisation has continued to be problematic in developing countries including Nigeria. In addressing the problems, policy in Nigeria is largely directed at overcoming socio cultural issues surrounding parents’ rejection of vaccines. However, determinants of immunisation have geographical implications as well. A cross sectional survey was used to select 484 mothers/caregivers through a multi stage cluster sampling technique from the three senatorial districts of Borno State, Nigeria. Mothers or caregivers of children 12–23 months were interviewed using a structured questionnaire adapted from the Nigeria Demographic and Health Survey (2008). Socio cultural factors measured include mother’s education, religion, husband’s permission and sex of child while spatial variables include location i.e. whether rural or urban, and distance measured in terms of physical distance, cost and perception of physical distance. Descriptive statistics, univariate and multivariate logistic regressions were used to analyse the results. Data indicate that only 10.5% of children were fully immunised. Though immunisation uptake differed between the senatorial districts, this was not significant (P=0.1). In the bivariate analysis, mothers living in urban areas, <1 km to immunisation centre, their perception of travel distance and travel cost were the spatial predictors of immunisation while literacy and husband’s permission were the socio-cultural factors of significance. However, in the multivariate regression only two geographical factors i.e. living in an urban area [odds ratio (OR) 3.42, confidence interval (CI) 1.40–8.33] and mothers’ perception of distance (OR 4.52, CI 2.14–9.55) were protective against under immunisation while mother’s education was the only socio cultural variable of significance (OR 0.10, CI 0.03–0.41). It was concluded that while it is important to address socio cultural issues, policies directed at overcoming the friction of distance especially mobile clinics in rural areas are required to significantly improve immunisation uptake in the state.

Factors predicting completion of the human papillomavirus vaccine series

PURPOSE

This study identified factors associated with completion of the three dose quadrivalent human papillomavirus vaccine (HPV4) series by female adolescents.

METHODS

Between February and September 2008, we prospectively surveyed 11- to 26-year-old female members of an integrated managed care organization shortly after their first HPV4 dose to identify factors that predicted series completion. We used regression analyses to assess whether self-reported experiences at the index visit, knowledge/attitudes about HPV and HPV4, and medical record data on adverse events, demographic characteristics, care-utilization frequency, and visit characteristics, were associated with vaccine series completion within one year of the first HPV4 dose.

RESULTS

Of 899 survey respondents (27% of 3347 survey recipients), 786 (87%) maintained continuous enrollment in the health plan in the year following the first HPV4 dose. Fifty percent (n = 393) completed the vaccine series within that year. In multivariate analyses of survey respondents, only respondents' ability to correctly identify the number of shots required for series completion was significantly associated with series completion. Reported bruising was associated with decreased likelihood of completion, and the clinician stating that future shots were required was associated with increased likelihood, but both were of borderline significance. Females ages 16-20 had the lowest series completion.

CONCLUSIONS

Improving HPV4 completion will require targeted efforts. Our results suggest that providers may help by stressing the need for additional doses of vaccine, and confirming that patients understand this information. Special attention should be given to females ages 16-20. Future randomized trials should assess the effect on vaccine completion of these simple, low-cost interventions.

Socioeconomic and racial/ethnic disparities in the incidence of bacteremic pneumonia among US adults

OBJECTIVES

We examined associations between the socioeconomic characteristics of census tracts and racial/ethnic disparities in the incidence of bacteremic community-acquired pneumonia among US adults.

METHODS

We analyzed data on 4870 adults aged 18 years or older with community-acquired bacteremic pneumonia identified through active, population-based surveillance in 9 states and geocoded to census tract of residence. We used data from the 2000 US Census to calculate incidence by age, race/ethnicity, and census tract characteristics and Poisson regression to estimate rate ratios (RRs) and 95% confidence intervals (CIs).

RESULTS

During 2003 to 2004, the average annual incidence of bacteremic pneumonia was 24.2 episodes per 100 000 Black adults versus 10.1 per 100 000 White adults (RR = 2.40; 95% CI = 2.24, 2.57). Incidence among Black residents of census tracts with 20% or more of persons in poverty (most impoverished) was 4.4 times the incidence among White residents of census tracts with less than 5% of persons in poverty (least impoverished). Racial disparities in incidence were reduced but remained significant in models that controlled for age, census tract poverty level, and state.

CONCLUSIONS

Adults living in impoverished census tracts are at increased risk of bacteremic pneumonia and should be targeted for prevention efforts.

Mapping and measuring disparities in welfare for cats across neighborhoods in a large US city

OBJECTIVE

To determine whether disparities in health and welfare among cats are present within neighborhoods and across census tracts in a large US city, and to compare results with area-level human data.

SAMPLE POPULATION

17,587 cat intake records from 2 animal sheltering organizations serving Boston, and summary data from city animal control authorities for a 5-year period (2004 through 2008).

PROCEDURES

Geocoded addresses (n = 15,285) were spatially joined to neighborhood and census tract polygons. Cat intakes and deaths were calculated per capita and compared with human demographic and death data. Poisson mixed-effects models were used to smooth mortality rates and calculate relative risks.

RESULTS

Data from geocoded records indicated that annual rates of cat intakes and deaths ranged widely (0.85 to 10.3 cats/1,000 persons and 0.27 to 3.9 cats/1,000 persons, respectively) within 16 neighborhoods of Boston. The disparity across 156 census tracts that comprised these neighborhoods was even greater (0.10 to 22.1 cats/1,000 persons and 0.15 to 6.47 cats/1,000 persons for intakes and deaths, respectively). Cat deaths were significantly correlated with human premature deaths at the neighborhood level (R2 = 0.77). Overall, annual per capita city-wide shelter-associated mortality rate for cats (estimated at approx 2.6 cats/1,000 persons) was similar to rates in other progressive communities.

CONCLUSIONS AND CLINICAL RELEVANCE

By use of geospatial techniques, 14- to 40-fold gradients in cat deaths were detected across Boston neighborhoods and census tracts. Cat deaths were associated with human premature deaths and socioeconomic indicators reflecting deprivation. Targeted interventions may be effective in resolving these disparities.

The immunization status of home-schooled children in America

The immunization of children against a vast number of life-threatening infectious agents has been hailed as one of the greatest public health interventions of the twentieth century. In America, the morbidity and mortality associated with many common childhood infectious diseases has all but vanished. State-based school entry vaccination laws play a significant role in achieving high immunization rates among children and adolescents. Alarmingly, there is no consistent regulation in place to monitor the immunization status of the ever-growing home-schooled population. It is widely unknown whether the nearly 2 million home-schooled children are adequately immunized. As the home schooling movement continues to gain ground in the United States, pediatric nurse practitioners in the primary care setting will play an important role in protecting the health of these children, as well as the public's health.