Addressing Determinants of Immunization Inequities Requires Objective Tools to Devise Local Solutions.

Universal immunization substantially reduces morbidity and mortality from vaccine-preventable diseases. In recent years, routine immunization coverage has varied considerably among countries across the WHO European Region, and among different populations and districts within countries. It has even declined in some countries. Sub-optimal immunization coverage contributes to accumulations of susceptible individuals and can lead to outbreaks of vaccine-preventable diseases. The European Immunization Agenda 2030 (EIA2030) seeks to build better health in the WHO European Region by ensuring equity in immunization and supporting immunization stakeholders in devising local solutions to local challenges. The factors that influence routine immunization uptake are context specific and multifactorial; addressing immunization inequities will require overcoming or removing barriers to vaccination for underserved individuals or populations. Local level immunization stakeholders must first identify the underlying causes of inequities, and based on this information, tailor resources, or service provision to the local context, as per the organization and characteristics of the health care system in their countries. To do this, in addition to using the tools already available to broadly identify immunization inequities at the national and regional levels, they will need new pragmatic guidance and tools to address the identified local challenges. It is time to develop the necessary guidance and tools and support immunization stakeholders at all levels, especially those at the subnational or local health centre levels, to make the vision of EIA2030 a reality.

Household Composition and Inequalities in COVID-19 Vaccination in Wales, UK.

The uptake of COVID-19 vaccination in Wales is high at a population level but many inequalities exist. Household composition may be an important factor in COVID-19 vaccination uptake due to the practical, social, and psychological implications associated with different living arrangements. In this study, the role of household composition in the uptake of COVID-19 vaccination in Wales was examined with the aim of identifying areas for intervention to address inequalities. Records within the Wales Immunisation System (WIS) COVID-19 vaccination register were linked to the Welsh Demographic Service Dataset (WDSD; a population register for Wales) held within the Secure Anonymised Information Linkage (SAIL) databank. Eight household types were defined based on household size, the presence or absence of children, and the presence of single or multiple generations. Uptake of the second dose of any COVID-19 vaccine was analysed using logistic regression. Gender, age group, health board, rural/urban residential classification, ethnic group, and deprivation quintile were included as covariates for multivariable regression. Compared to two-adult households, all other household types were associated with lower uptake. The most significantly reduced uptake was observed for large, multigenerational, adult group households (aOR 0.45, 95%CI 0.43-0.46). Comparing multivariable regression with and without incorporation of household composition as a variable produced significant differences in odds of vaccination for health board, age group, and ethnic group categories. These results indicate that household composition is an important factor for the uptake of COVID-19 vaccination and consideration of differences in household composition is necessary to mitigate vaccination inequalities.

Determinants of Equity in Coverage of Measles-Containing Vaccines in Wales, UK, during the Elimination Era.

In the context of the WHO's measles and rubella elimination targets and European Immunization Agenda 2030, this large cross-sectional study aimed to identify inequalities in measles vaccination coverage in Wales, UK. The vaccination status of individuals aged 2 to 25 years of age, alive and resident in Wales as of 31 August 2021, was ascertained through linkage of the National Community Child Health Database and primary care data. A series of predictor variables were derived from five national datasets and all analysis was carried out in the Secure Anonymised Information Linkage Databank at Swansea University. In these 648,895 individuals, coverage of the first dose of measles-containing vaccine (due at 12-13 months of age) was 97.1%, and coverage of the second dose (due at 3 years and 4 months) in 4 to 25-year-olds was 93.8%. In multivariable analysis, excluding 0.7% with known refusal, the strongest association with being unvaccinated was birth order (families with six or more children) and being born outside of the UK. Living in a deprived area, being eligible for free school meals, a lower level of maternal education, and having a recorded language other than English or Welsh were also associated with lower coverage. Some of these factors may also be associated with refusal. This knowledge can be used to target future interventions and prioritise areas for catch up in a time of limited resource.

Inequalities in coverage of COVID-19 vaccination: A population register based cross-sectional study in Wales, UK.

The COVID-19 pandemic has highlighted existing health inequalities for ethnic minority groups and those living in more socioeconomically deprived areas in the UK. With higher levels of severe outcomes in these groups, equitable vaccination coverage should be prioritised. The aim of this study was to identify inequalities in coverage of COVID-19 vaccination in Wales, UK and to highlight areas which may benefit from routine enhanced surveillance and targeted interventions. Records within the Wales Immunisation System (WIS) population register were linked to the Welsh Demographic Service Dataset (WDSD) and central list of shielding patients, held within the Secure Anonymised Information Linkage (SAIL) Databank. Ethnic group was derived from the 2011 census and over 20 administrative electronic health record (EHR) data sources. Uptake of first dose of any COVID-19 vaccine was analysed over time, with the odds of being vaccinated as at 25th April 2021 by sex, health board of residence, rural/urban classification, deprivation quintile and ethnic group presented. Using logistic regression models, analyses were adjusted for age group, care home resident status, health and social care worker status and shielding status. This study included 1,256,412 individuals aged 50 years and over. Vaccine coverage increased steadily from 8th December 2020 until mid-April 2021. Overall uptake of first dose of COVID-19 vaccine in this group was 92.1%. After adjustment the odds of being vaccinated were lower for individuals who were male, resident in the most deprived areas, resident in an urban area and an ethnic group other than White. The largest inequality was seen between ethnic groups, with the odds of being vaccinated 0.22 (95 %CI 0.21-0.24) if in any Black ethnic group compared to any White ethnic group. Ongoing monitoring of inequity in uptake of vaccinations is required, with better targeted interventions and engagement with deprived and ethnic communities to improve vaccination uptake.

Timeliness and equity of infant pertussis vaccination in wales: Analysis of the three dose primary course.

Infants aged under one year are at the highest risk of severe complications or death from pertussis infection. Prompt vaccination with a three dose course at two, three and four months of age decreases the amount of time they are vulnerable following waning of maternal antibodies. In Wales, uptake of all three doses of the primary course of pertussis containing vaccine is high. However, timeliness and equity at a population level have not been previously reported. This analysis included 163,733 children born from 1st January 2013 to 31st December 2017. In this cohort 87.9% received the first dose of a pertussis containing vaccine by 12 weeks of age, 87.1% had received all three doses by 24 weeks of age, and 96.3% received three doses by 52 weeks of age. Differences in uptake between those living in the most deprived and least deprived quintiles of Lower Super Output Area (LSOA) were smaller than differences in timeliness, but statistically significant. In 2017 the difference in timely uptake between those living in the most and least deprived quintiles was 4%, 5% and 7% for doses one, two and three respectively. There was a difference of 10% in the proportion of infants receiving all three primary vaccinations on time between the most and least deprived quintile of LSOAs. Consideration is needed on interventions that will help improve timeliness such as enhanced follow up of defaulters, electronic communication between primary care data systems, enhanced health visitor intervention and opportunistic vaccination in those who fail to attend scheduled vaccination appointments. There is also the need for routine monitoring of timeliness and further research into what influences delayed vaccination.

Inequalities in vaccination coverage and differences in follow-up procedures for asylum-seeking children arriving in Wales, UK.

The European Vaccine Action Plan 2015-2020 highlights the importance of reducing inequities and monitoring performance in underserved groups including migrants. However, there are limited data from European countries and policies for catch-up vary by country. Vaccination coverage in accompanied asylum-seeking children aged 5 to 16 years in two dispersal areas of Wales is presented alongside the coverage in the local population. Coverage data for asylum-seeking children were collated locally using asylum seeker nurse records whilst coverage in the local population was calculated using data from the National Community Child Health Database, a repository of data from all local Child Health Systems in Wales. The processes for following up outstanding vaccinations were also collected using a face-to-face questionnaire distributed to lead asylum seeker nurses in each area. As at the date of assessment, 45.6% (67/147) of children dispersed to area one had received all recommended immunisations compared with 62.2% (150/241) dispersed to area two, OR 0.51 (95% CI 0.33-0.79). At both sites the odds of being vaccinated against key vaccine preventable infections were around three times lower if you were an asylum-seeking child, compared with the local population. Similar procedures were in place for new asylum seekers in both dispersal areas. Area one had less resource to follow up missing immunisations, and children did not receive an initial health assessment unlike area two. Verbal history was accepted in area one but not in area two, despite area two having higher vaccine uptake.Conclusion: Asylum-seeking children have low rates of vaccine uptake compared with the general population, although uptake differs depending on dispersal area. Inequalities in vaccination services, such as resource and strategies to improve uptake, need to be considered.What is Known:• The European Vaccine Action Plan 2015-2020 highlights the importance of reducing inequities and monitoring performance in underserved groups including migrants.• Limited data from European countries suggest inequalities in uptake of immunisations in migrants compared with the local population. Policies for catching up immunisations vary by country.What is New:• Despite national policy for vaccination of migrants with missing or incomplete vaccination history in Wales, this work suggests vaccination coverage in asylum-seeking children is not equitable with the local population.• Vaccination coverage in asylum-seeking children dispersed to different areas of Wales also varies, and this may be associated with differences in local catch-up strategies and the ability to follow national policy. Resource and strategies to maintain engagement with health services play an important role in increasing vaccine uptake in underserved groups.

Measuring inequalities in immunization in Wales and the impact of interventions.

We reviewed uptake of childhood immunization in Wales by quintile of deprivation and found that uptake was significantly lower in residents in the most socio-economically deprived areas compared with the least deprived. Differences were greater in older children. Services generally met best practice recommended by the National Institute for Health and Care Excellence; however, follow up of children who had not responded to invitations to attend routine immunization sessions needed more consistent implementation. Over a three year period to 2014-15 the difference in uptake between upper and lower quintiles at the fourth birthday reduced from 8.9% to 6.7%.