Vaccination Timeliness at Age 24 Months in Michigan Children Born 2006-2010

Timeliness for vaccination according to the expanded immunization program in children under 6 years of age in Colombia between 2014 and 2019

The aim was to estimate the vaccination timeliness defined as the proportion of children under 6 years of age who received their immunization in the time range established by the Colombian Expanded Immunization Program (EIP). A retrospective cohort study that collected reports of vaccination opportunities between 2014 and 2019 provided by the Ministry of Health. Age, sex, city, ethnicity, health system affiliation regimen, vaccine applied, and timing of vaccination were considered for the time range under study. A total of 3,370,853 immunized children were included from all regions of the country. More than 80% of children had a timeliness to get most vaccines. The exceptions were yellow fever (17%) and seasonal influenza (42%). No differences in timeliness were found according to geographic region or by health system affiliation regime, but the average timeliness for all vaccines of children of the indigenous population (65.8% ±18.4%) was lower than that of the rest of the population (78·6% ± 19·3%) (p = 0·021). The timeliness for vaccination under the EIP of Colombia is high, with proportions of 72-96%, but intergroup differences were identified, mainly lower timeliness among indigenous people. These findings warrant improvement strategies that would guarantee the immunization of the entire child population.

Acceptance of a Future Gonorrhea Vaccine in a Post-Coronavirus Disease 2019 World: Impact of Type of Recommendation and Changing Levels of Trust in Health Institutions and Authorities

Widespread uptake of a future gonorrhea vaccine could decrease the burden of disease and limit the spread of antibiotic resistance. However, gonorrhea vaccination will occur in the backdrop of the roll-out of the coronavirus disease 2019 (COVID-19) vaccine, which could have influenced parental perceptions about other, non-COVID-19 vaccines. In an internet-based cross-sectional survey, 74% of parents would get a gonorrhea vaccine for their child, and this was higher among those whose trust in pharmaceutical companies increased since the start of the COVID-19 pandemic. About 60% of adults aged 18 to 45 would receive a vaccine for themselves.

Beyond Vaccination Coverage: Population-Based Measurement of Early Childhood Immunization Schedule Adherence

The immunization schedule recommended by the U.S. Advisory Committee on Immunization Practices (ACIP) provides a structure for how 10 different vaccine series should be administered to children in the first 18 months of life. Progress toward US early childhood immunization goals has largely focused on measuring vaccination coverage at age 24 months. However, standard vaccination coverage measures do not reflect whether children received vaccine doses by recommended ages, or whether vaccines were given concomitantly, per the schedule. In this paper, we describe innovations in population-level measurement of immunization schedule adherence through quantifying vaccination timeliness and undervaccination patterns. Measuring vaccination timeliness involves comparing when children received vaccine doses relative to ACIP age recommendations. To assess undervaccination patterns, children's vaccination histories are analyzed to determine whether they were vaccinated consistent with the ACIP schedule. Some patterns, such as spreading out vaccines across visits, are indicative of parental hesitancy. Other patterns, such as starting all recommended series but missing doses, are largely indicative of other immunization services delivery challenges. Since 2003, at least 12 studies have used National Immunization Survey-Child, immunization information system, or integrated health plan data to measure vaccination timeliness or undervaccination patterns at national or state levels. Moving forward, these novel measures can be leveraged for population-based surveillance of vaccine confidence, and for distinguishing undervaccination due to parental vaccine hesitancy from undervaccination due to other causes. Broader adoption of these measures can facilitate identification of targeted strategies for improving timely and routine early childhood vaccination uptake across the United States.

Hepatitis B Vaccination of Low Birth Weight Infants in Washington State

OBJECTIVE

The U.S. Advisory Committee on Immunization Practices (ACIP) recommends that infants born weighing less than 2,000 g receive the hepatitis B (HepB) vaccine at hospital discharge or 30 days of age. This study aimed to assess timely HepB vaccination among low birth weight infants. We hypothesized that many of these vulnerable infants would fail to receive their HepB birth dose on time.

STUDY DESIGN

This retrospective cohort study included Washington State infants born weighing less than 2,000 g at an academic medical center between 2008 and 2013. Data were abstracted from electronic health records and linked to vaccine data from the Washington State Immunization Information System. Multivariable logistic regression was used to examine the associations between sociodemographic, clinical, and visit characteristics and HepB vaccination by birth hospitalization discharge or 30 days of age.

RESULTS

Among 976 study infants, 58.4% received their HepB vaccine by birth hospitalization discharge or 30 days of age. Infants had higher odds of timely HepB vaccination if they were Hispanic (adjusted odds ratio [AOR] = 1.80, 95% confidence interval [CI]: 1.10-2.95) or non-Hispanic black (AOR = 2.28, 95% CI: 1.36-3.80) versus non-Hispanic white or if they were hospitalized 14 days or longer versus less than 14 days (AOR = 2.43, 95% CI: 1.66-3.54). Infants had lower odds of timely HepB vaccination if they were born before 34 weeks versus on or after 34 weeks of gestational age (AOR = 0.41, 95% CI: 0.27-0.63) or if they had an estimated household income less than $50,845 versus 50,845 or greater (AOR = 0.64, 95% CI: 0.48-0.86).

CONCLUSION

Many infants born weighing less than 2,000 g did not receive their first HepB birth dose according to ACIP recommendations. Strategies are needed to improve timely HepB vaccination in this high-risk population.

KEY POINTS

· Low birth weight infants are at increased risk for vaccine preventable diseases.. · Many of these vulnerable infants failed to receive their first hepatitis B vaccine on time.. · This study identified key factors associated with timely hepatitis B vaccination..

Adherence to the paediatric immunisation schedule in England

Both adequate coverage and adherence to paediatric immunisation schedules are required for optimal protection against vaccine preventable diseases. We studied the timeliness of routine paediatric vaccinations according to the NHS’s immunisation schedule and potential factors of schedule adherence. Immunisation data was obtained from the Royal College of General Practitioners (RCGP) Research and Surveillance Centre (RSC). We collected vaccine types, doses, and dates for all routine paediatric vaccines between 2008 and 2018: DTaP/IPV/Hib/HepB, DTaP/IPV/Hib, DTaP/IPV, dTaP/IPV, Td/IPV, MMR, PCV, MenB, MenC, MenACWY, Hib/MenC, RV, HPV. Adherence to the immunisation schedule was calculated for each vaccine and dose. Differences in adherence between genders, NHS regions, and IMD quintiles were analysed. Our study included 6′257′828 vaccinations in 1′005′827 children. Seventy-five percent of first doses were administered within one (for vaccines scheduled in the first year of life) or two months (for vaccines scheduled later in life) following the recommended age, 19% too late and 6% too early. About half of the subsequent doses were given timely. The time between first and second doses was too short for 36% of vaccinations while 13% of second doses were administered too long after the first dose. Third doses were administered timely for 45%, too short for 37%, and too long for 18% of vaccinations. Differences in immunisation schedule adherence between girls and boys were negligible, except for HPV, and differences between the four main NHS regions were small. Overall, immunisation schedule adherence improved slightly with decreasing deprivation according to the Index of Multiple Deprivation. Efforts are required to improve the timeliness of paediatric vaccinations and to assure adequate protection against vaccine preventable diseases. We propose developing a compound measure combining coverage and adherence to provide a better indication of the protection against vaccine preventable diseases in a community.

Delays in routine childhood vaccinations and their relationship with parental vaccine hesitancy: a cross-sectional study in Wuxi, China

OBJECTIVES

This study aimed to examine childhood vaccination delay, explore the association between vaccination delay and parental vaccine hesitancy, and assess childhood vaccination delays during the coronavirus disease (COVID)-19 pandemic in China.

METHODS

This cross-sectional survey was conducted in Wuxi City. Participants were recruited from local vaccination clinics. Questionnaires were used to collect information about socio-demographics, vaccine hesitancy, and immunization clinic evaluations. Vaccination records were obtained from the Jiangsu Information Management System of Vaccination Cases.

RESULTS

Overall, 2728 participants were included. The coverage for seven category A vaccines (Expanded Program on Immunization (EPI)) was more than 95% at 24 months. The proportion of children vaccinated in a timely manner was the highest for the first dose of the hepatitis B vaccine (91.6%) and the lowest for the Bacillus-Calmette-Guerin vaccine (44.6%). More than 50% of the planned vaccinations were delayed in February and March 2020. The Vaccine Hesitancy Scale scores were not associated with vaccination delay (P = 0.842). Children's vaccination delays were negatively associated with parents who reported convenient access to clinics and satisfaction with immunization services (P = 0.020, P = 0.045).

CONCLUSIONS

EPI is highly successful in China. Despite vaccination delays due to the COVID-19 pandemic, coverage was recovered after lockdown restrictions were eased.

The Use of Digital Technologies to Support Vaccination Programmes in Europe: State of the Art and Best Practices from Experts' Interviews

Digitalisation offers great potential to improve vaccine uptake, supporting the need for effective life-course immunisation services. We conducted semi-structured in-depth interviews with public health experts from 10 Western European countries (Germany, Greece, Italy, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, and the United Kingdom) to assess the current level of digitalisation in immunisation programmes and retrieve data on interventions and best practices. Interviews were performed using an ad hoc questionnaire, piloted on a sample of national experts. We report a mixed level of digital technologies deployment within vaccination services across Europe: Some countries are currently developing eHealth strategies, while others have already put in place robust programmes. Institutional websites, educational videos, and electronic immunisation records are the most frequently adopted digital tools. Webinars and dashboards represent valuable resources to train and support healthcare professionals in immunisation services organisation. Text messages, email-based communication, and smartphone apps use is scattered across Europe. The main reported barrier to the implementation of digital-based programmes is the lack of resources and shared standards. Our study offers a comprehensive picture of the European context and shows the need for robust collaboration between states and international institutions to share best practices and inform the planning of digital intervention models with the aim of countering vaccine hesitancy and increasing vaccine uptake.

Timeliness of Early Childhood Vaccinations and Undervaccination Patterns in Montana

INTRODUCTION

Early childhood vaccination rates are lower in rural areas than those in urban areas of the U.S. This study's objective is to quantify vaccine timeliness and the prevalence of undervaccination patterns in Montana and to measure the associations between timeliness and series completion by age 24 months.

METHODS

Using records from January 2015 to November 2019 in Montana's centralized immunization information system, days undervaccinated were calculated for the combined 7-vaccine series. Undervaccination patterns indicative of certain barriers to vaccination, including parental vaccine hesitancy, were identified. Using multivariable log-linked binomial regression, the association between timing of vaccine delay and not completing the combined 7-vaccine series by age 24 months was assessed. Analyses were conducted in March 2020-August 2020.

RESULTS

Among 31,422 children, 38.0% received all vaccine doses on time; 24.3% received all doses, but some were received late; and 37.7% had not completed the combined 7-vaccine series. Approximately 18.7% had an undervaccination pattern suggestive of parental vaccine hesitancy, and 19.7% started all series but were missing doses needed for multidose series completion. Although falling behind on vaccinations at any age was associated with failing to complete the combined 7-vaccine series, being late at age 12-15 months had the strongest association (adjusted prevalence ratio=3.73, 95% CI=3.56, 3.91) compared with being on time at age 12-15 months.

CONCLUSIONS

Fewer than 2 in 5 Montana children were fully vaccinated on time for the combined 7-vaccine series. To increase vaccination rates, initiatives to increase vaccine confidence and remind parents to complete vaccine series are needed.

Timeliness, completeness, and timeliness-and-completeness of serial routine vaccinations among rural children in Southwest China: A multi-stage stratified cluster sampling survey

INTRODUCTION

Vaccination coverage is widely used as metric of vaccination programme performance. However, VPDs outbreaks were reported in areas with high vaccination coverage. Timeliness and completeness have been considered more important assessment indicators of routine vaccination than overall vaccination coverage, but little is known in rural China. This study aimed to assess the timeliness and completeness of serial routine vaccinations among children in rural Southwest China.

METHODS

A multi-stage stratified cluster survey was conducted among 1062 children aged 18-48 months in rural Guangxi. Vaccination status was obtained from child's vaccination certificate. We calculated timely vaccination coverage, complete vaccination coverage, timely-and-complete vaccination coverage and 95% CI for routine vaccination through weighted estimation analysis. Weighted Kaplan-Meier analyses were applied to estimate the median delay periods for each dose of serial routine vaccines, including one-dose BCG, three-dose HepB, three-dose OPV, four-dose DTP, two-dose MCV, two-dose JEV and two-dose MPV-A. Complete coverage, and timely-and-complete coverage for combined 5-vaccine series were calculated.

RESULTS

For each dose of routine vaccines, overall vaccination coverages were over 90%, but timely vaccination coverage ranged from the lowest of 44.4% for JEV1 to the highest of 92.5% for MPV-A1. For multi-dose routine vaccines, complete vaccination coverages varied from the lowest of 92.9% for MCV to the highest of 100% for HepB, and timely-and-complete vaccination coverages were lower than 80%, ranging from the lowest of 30% for JEV to the highest of 77.2% for MPV-A. For combined 5-vaccine series, complete coverage was 77%, while timely-and-complete coverage was 12.1%. MPV-A1 had the longest median delay of 176 days, but BCG and HepB1 had the shortest of 1 day.

CONCLUSIONS

The overall coverages of serial routine vaccinations were high, but the timeliness and completeness were poor. Relevant agencies of vaccination service should address timeliness-and-completeness into the assessment indicators of routine vaccination service quality.

Timeliness of Childhood Vaccination Coverage: the Growing Up in Singapore Towards Healthy Outcomes Study

Studies investigating timeliness for childhood vaccination are limited especially in Asia. We examined the timeliness of vaccine administration and associated factors among infant and young children in Singapore. A total of 782 children born between November 2009 and July 2011 from a prospective cohort in Singapore were studied. Vaccination records from birth to 24 months of age were obtained from the National Immunization Registry of Singapore. Multivariable logistic regression models were performed. By 2 years of age, 92.8% of children in our cohort experienced a delay in receiving 1 or more vaccine doses according to the recommended national immunization schedule. When vaccinations were reviewed by series for each vaccine, 15.6% received all vaccine series outside the recommended age ranges. Factors associated with receiving vaccination series outside the recommended ages included maternal aged ≤ 35 years (OR 2.00; 95% CI 1.09, 3.66), Malay (1.71; 1.01, 2.89) or Indian ethnicity (2.06; 1.19, 3.59), low monthly household income (1.91; 1.14, 3.18), having at least four children (3.46; 1.62, 7.38) and private (3.42; 1.80, 6.48) and multiple vaccination providers (3.91; 1.23, 12.48). These findings show an unacceptably high proportion of children experienced a delay in the receipt of their vaccinations. The identification of several demographic, socioeconomic, health-seeking behavioural and vaccine provider factors provides opportunities for targeted interventions to enhance the timeliness of childhood vaccination in Singapore.

Hepatitis B Birth Dose Effects on Childhood Immunization in the U.S

INTRODUCTION

The Advisory Committee on Immunization Practices recommends administering the first dose of hepatitis B vaccine at birth, making it the first vaccine that many children receive. However, few studies examine whether children who miss the birth dose are at increased risk of vaccination delay. This study investigates birth dose as a determinant of up-to-date immunization status at age 18 months, considering 7 core childhood vaccine series: diphtheria, tetanus, and acellular pertussis; polio; measles, mumps, and rubella; Haemophilus influenzae type B; varicella; hepatitis B; and pneumococcal conjugate vaccine.

METHODS

Cross-sectional data were collected in 2017 by National Immunization Survey-Child, a nationally representative survey of children aged 19-35 months living in the U.S., and were analyzed in 2019. The primary outcome was combined 7-vaccine series (4:3:1:3:3:1:4) up-to-date status at 18 months. Doubly robust estimates of association were calculated using survey logistic regression and propensity scores estimated with boosted classification and regression trees.

RESULTS

Children who received the birth dose had 2.01 (95% CI=1.74, 2.33) times the odds of being up-to-date on the combined 7-vaccine series as children who did not. ORs for all the 7 individual vaccine series were positive, ranging from 1.59 (95% CI=1.28, 1.97) for measles, mumps, and rubella to 4.97 (95% CI=3.97, 6.24) for hepatitis B.

CONCLUSIONS

Receiving the birth dose is positively associated with up-to-date status later in childhood, highlighting the importance of starting vaccination early. The association is insensitive to confounding by factors observed in National Immunization Survey-Child, but investigation of unobserved factors such as vaccine hesitancy could provide critical information to guide intervention strategy.

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.

Vaccine Education, Reasons for Refusal, and Vaccination Behavior

INTRODUCTION

Little is known about associations between the reasons parents refuse or delay vaccines for their children, their responsiveness to vaccine counseling, and their children's vaccination status at various ages. Since 2015, Michigan has required parents to attend education sessions at local health departments to receive nonmedical exemptions. This requirement provides an opportunity to study otherwise opaque aspects of vaccine refusal.

METHODS

In 2017 and 2018, researchers analyzed a combined data set that included electronic medical records (n=4,098) generated by one Michigan health department during 2015 immunization education sessions, and immunization records from an August 2016 report of the Michigan Care Improvement Registry immunization registry. Analyses employed difference of proportions and ANOVAs to explore group differences in vaccination behaviors after education sessions and on-time vaccination status at various ages.

RESULTS

Children whose parents stated a commitment to an alternative schedule at the education session subsequently received a vaccine their parents had refused at a much higher rate (39.2%) than did children whose parents refused for reasons of religion (4.4%), concerns about the risks of vaccines (8.1%), or beliefs that vaccines provide little benefit (10.5%).

CONCLUSIONS

Different reasons for refusal are associated with different patterns of vaccination behavior. Furthermore, results suggest that education sessions may overcome vaccine refusal in some cases, and that distinct refusal reasons mark real differences in parental motivations regarding vaccination choices. These differences in parental motivations may indicate the existence of different sites for potential pro-vaccination interventions.

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.