Positioning implementation science in national immunization programmes to improve coverage equity and advance progress toward Immunization Agenda 2030: An urgent global health imperative.

Despite the availability of effective vaccines for preventing common childhood infectious diseases, there is still significant disparities in access and utilization across many low- and middle-income countries (LMIC). The factors that drive these disparities are often multilevel, originating from individuals, health facilities, health systems and communities, and also multifaceted. Implementation science has emerged as a field to help address "know-do" gaps in health systems, and can play a significant role in strengthening immunization systems to understand and solve implementation barriers that limit access and uptake within their contexts. This article presents a reflexive perspective on how to position implementation research in immunization programmes to improve coverage equity. Furthermore, key points of synergy between implementation research and vaccination are highlighted, and some potential practice changes that can be applied within specific contexts were proposed. Using a human rights lens, it was concluded that the cost that is associated with implementation failure in immunization programmes is significant and unjust, and future directions for implementation research to optimize its application in practice settings have been recommended.

Sustainable financing for vaccination towards advancing universal health coverage in the WHO African region: The strategic role of national health insurance.

There is a growing political interest in health reforms in Africa, and many countries are choosing national health insurance as their main financing mechanism for universal health coverage. Although vaccination is an essential health service that can influence progress toward universal health coverage, it is not often prioritized by these national health insurance systems. This paper highlights the potential gains of integrating vaccination into the package of health services that is provided through national health insurance and recommends practical policy actions that can enable countries to harness these benefits at population level.

Health trends, inequalities and opportunities in South Africa's provinces, 1990-2019: findings from the Global Burden of Disease 2019 Study.

BACKGROUND: Over the last 30 years, South Africa has experienced four 'colliding epidemics' of HIV and tuberculosis, chronic illness and mental health, injury and violence, and maternal, neonatal, and child mortality, which have had substantial effects on health and well-being. Using data from the 2019 Global Burden of Diseases, Injuries and Risk Factors Study (GBD 2019), we evaluated national and provincial health trends and progress towards important Sustainable Development Goal targets from 1990 to 2019. METHODS: We analysed GBD 2019 estimates of mortality, non-fatal health loss, summary health measures and risk factor burden, comparing trends over 1990-2007 and 2007-2019. Additionally, we decomposed changes in life expectancy by cause of death and assessed healthcare system performance. RESULTS: Across the nine provinces, inequalities in mortality and life expectancy increased over 1990-2007, largely due to differences in HIV/AIDS, then decreased over 2007-2019. Demographic change and increases in non-communicable diseases nearly doubled the number of years lived with disability between 1990 and 2019. From 1990 to 2019, risk factor burdens generally shifted from communicable and nutritional disease risks to non-communicable disease and injury risks; unsafe sex remained the top risk factor. Despite widespread improvements in healthcare system performance, the greatest gains were generally in economically advantaged provinces. CONCLUSIONS: Reductions in HIV/AIDS and related conditions have led to improved health since 2007, though most provinces still lag in key areas. To achieve health targets, provincial governments should enhance health investments and exchange of knowledge, resources and best practices alongside populations that have been left behind, especially following the COVID-19 pandemic.

Incomplete vaccination and associated factors among children aged 12-23 months in South Africa: an analysis of the South African demographic and health survey 2016.

BACKGROUND: Socioeconomic and health inequalities remain a huge problem in post-apartheid South Africa. Despite substantial efforts at ensuring universal access to vaccines, many children remain under-vaccinated in the country. This study aimed to assess the prevalence and factors associated with incomplete vaccination in the first year of life, among children aged 12-23 months in South Africa. METHODS: The study is a secondary analysis of the 2016 South African Demographic and Health Survey. A multivariable logistic regression model was applied to the data on 708 children aged 12-23 months. The study outcome, vaccination completeness, was assessed using a composite assessment of nine doses of four vaccines; Bacillus Calmette-Guérin (BCG) (one dose), Polio (four doses), diphtheria-tetanus-pertussis containing vaccines (DTP) (three doses) and measles-containing vaccines (MCV) (one dose). Children who received all the nine doses were categorized as completely vaccinated. Independent variables included child, maternal, and demographic characteristics. Variables were included in the model based on literature findings. Bivariate analyses were used to examine the crude association between each independent variable and incomplete vaccination, while the multivariable logistic regression model was used to examine the adjusted association after controlling for other variables. Measures of association were presented as odds ratios (OR) with their 95% confidence intervals (CI). RESULTS: About two-fifths (40.8%) of the children were incompletely vaccinated. The prevalence of incomplete vaccination was significantly high among children whose mothers did not receive antenatal care (ANC) during pregnancy (57.5%), and children living in Gauteng Province (52.2%). From the bivariate analyses, the odds of being incompletely vaccinated were three times higher in children whose mothers did not attend ANC compared with children whose mothers attended ANC (crude OR = 2.93; 95% CI 1.42-6.03). The odds were about three times higher in children living in Mpumalanga province (OR = 2.58; 95% CI 1.27-5.25) and in those living in Gauteng province (OR = 2.76; 95% CI 1.30-5.91), compared with those living in Free State province. Conversely, the odds were 32% lower in children from rich households, compared with those from poor households (OR = 0.68; 95% CI 0.47-0.98). In the adjusted model, the higher odds of incomplete vaccination in children whose mothers did not attend ANC were maintained in both magnitude and direction (adjusted OR [aOR] = 2.87; 95% CI 1.31-6.25). Similarly, compared with children living in Free State province, the higher odds of a child being incompletely vaccinated in Mpumalanga (aOR = 2.30; 95% CI 1.03-5.14) and in Gauteng (aOR = 3.10; 95% CI 1.35-7.15) provinces were maintained in both magnitude and direction. CONCLUSIONS: There is a substantial burden of incomplete childhood vaccination in South Africa. Maternal ANC attendance during pregnancy and area of residence significantly influences this burden. Interventions that promote broader health service utilization, such as ANC attendance, can help improve the awareness and uptake of routine childhood vaccination. It is also imperative to take into consideration the provincial disparities in childhood vaccination completeness, in planning and implementing interventions to improve vaccination coverage in the country.

Country-Level Assessment of Missed Opportunities for Vaccination in South Africa: Protocol for Multilevel Analysis.

BACKGROUND: Vaccination is one of the greatest public health interventions of all time. Vaccination coverage in South Africa has shown a steady improvement in reaching the national target. However, while there is progress nationally, there are districts within the country that are below the set target for vaccination coverage. One of the main drivers of suboptimal vaccination coverage is thought to be missed opportunities for vaccination. OBJECTIVE: This study aims to understand the magnitude and determinants of missed opportunities for vaccination in South Africa. METHODS: The 2016 South African Demographic and Health Survey will be used to conduct multilevel regression analyses to determine individual and contextual factors associated with missed opportunities for vaccination in South Africa. The perspectives of parents attending health care facilities in South Africa will be explored through exit interviews and focus group discussions. Similarly, perspectives of the health care providers will be sought to understand enablers and barriers to vaccination coverage at the facility level. Insights to such factors will aid in designing tailor-made interventions to improve vaccination coverage in South Africa. RESULTS: Ethical review submission is planned for October 2020. Data collection is expected to be underway in January 2021. CONCLUSIONS: The extent of missed opportunities in South Africa coupled with the associated factors presents an opportunity for efforts to increase uptake in districts where vaccination coverage is below the national target. Population-level data such as those from the 2016 South African Demographic Health Survey will provide an idea of the magnitude of missed opportunities for vaccination in South Africa at the national and subnational levels. The findings of the study will inform national and subnational policy implementation on vaccinations and help to find context-specific interventions to improve vaccination coverage. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/16672.

The burden of vaccine-preventable diseases among HIV-infected and HIV-exposed children in sub-Saharan Africa: a systematic review and meta-analysis.

There are knowledge gaps regarding evidence-based research on the burden of vaccine-preventable diseases among human immunodeficiency virus (HIV)-infected and HIV-exposed children aged <18 years in sub-Saharan Africa. It is therefore essential to determine the trend and burden of vaccine-preventable diseases. We completed a systematic review and meta-analysis to identify the incidence, prevalence and case-fatality rates (CFR) attributed to various vaccine-preventable diseases among HIV-infected and HIV-exposed children in sub-Saharan Africa. The trends in the prevalence of vaccine-preventable diseases among HIV-infected and HIV-exposed children were also determined. Nine studies on tuberculosis (TB) were pooled to give an overall incidence rate estimate of 60 (95% confidence interval [CI] 30-70) per 1,000 child-years. The incidence of pneumococcal infections varied between 109-1509 per 100,000 while pertussis was between 2.9 and 3.7 per 1000 child-year. Twenty-two TB prevalence studies reported an estimated prevalence of 16%. Fifteen prevalence studies on hepatitis B infection were pooled together with an estimated prevalence of 5%. The pooled prevalence for pneumococcal infections was 2% while rotavirus diarrhoea reported a prevalence of 13%. Twenty-nine studies on TB were pooled to give an overall CFR estimate of 17% while pneumococcal infections in HIV-infected and exposed children were pooled together with a resultant rate of 15%. Some of the vaccine-preventable diseases still have high incidences, prevalence and CFR among HIV-infected and HIV-exposed children. There is also a dearth of research data on the burden of several vaccine-preventable diseases among HIV-infected and exposed children and a need for more studies in this area.

Rural-urban disparities in missed opportunities for vaccination in sub-Saharan Africa: a multi-country decomposition analyses.

BACKGROUND: In this study, we aimed to explore the rural-urban disparities in the magnitude and determinants of missed opportunities for vaccination (MOV) in sub-Saharan Africa. METHODS: This was a cross-sectional study using nationally representative household surveys conducted between 2007 and 2017 in 35 countries across sub-Saharan Africa. The risk difference in MOV between rural or urban dwellers were calculated. Logistic regression method was used to investigate the urban-rural disparities in multivariable analyses. Then Blinder-Oaxaca method was used to decompose differences in MOV between rural and urban dwellers. RESULTS: The median number of children aged 12 to 23 months was 2113 (Min: 370, Max: 5896). There was wide variation in the the magnitude of MOV among children in rural and urban areas across the 35 countries. The magnitude of MOV in rural areas varied from 18.0% (95% CI 14.7 to 21.4) in the Gambia to 85.2% (81.2 to 88.9) in Gabon. Out of the 35 countries included in this analysis, pro-rural inequality was observed in 16 countries (i.e. MOV is prevalent among children living in rural areas) and pro-urban inequality in five countries (i.e. MOV is prevalent among children living in urban areas). The contributions of the compositional 'explained' and structural 'unexplained' components varied across the countries. However, household wealth index was the most frequently identified factor. CONCLUSIONS: Variation exists in the level of missed opportunities for vaccination between rural and urban areas, with widespread pro-rural inequalities across Africa. Although several factors account for these rural-urban disparities in various countries, household wealth was the most common.

Does it really matter where you live? A multilevel analysis of factors associated with missed opportunities for vaccination in sub-Saharan Africa.

There is an urgent need to examine the magnitude and factors responsible for missed opportunities for vaccination, to rapidly achieve national immunization targets. The objective of the study was to examine the influence of individual, neighbourhood and country level socioeconomic position on missed opportunities for vaccination (MOV) in Sub-Saharan Africa. We used multilevel logistic regression analysis on Demographic and Health Survey data collected between 2007 and 2016 in sub-Saharan Africa. We analysed data on 43,637 children aged 12 to 23 months (Level 1) nested within 15,122 neighbourhoods (Level 2) from 35 countries (Level 3). After adjustment for individual-, neighbourhood- and country-level factors, the following appeared as significant risk factors for increased odds of MOV: high birth order, high number of under-five children in the house, poorest household, lack of maternal education, lack of media access, and living in poorer neighbourhood. According to the intra-country and intra-neighbourhood correlation coefficient, 18.4% and 37.4% of the variance in odds of MOV could be attributed to the country and neighbourhood level factors, respectively; and if a child moved to another country or neighbourhood with a higher probability of MOV, the median increase in their odds of MOV would be 2.47 and 2.56 fold respectively. This study has revealed that the risk of missed opportunities for vaccination in sub-Saharan Africa is influenced by not only individual factors but also by compositional factors such as family's financial capacity, place of birth and upbringing.

Decomposing the gap in missed opportunities for vaccination between poor and non-poor in sub-Saharan Africa: A Multicountry Analyses.

Understanding the gaps in missed opportunities for vaccination (MOV) in sub-Saharan Africa would inform interventions for improving immunisation coverage to achieving universal childhood immunisation. We aimed to conduct a multicountry analyses to decompose the gap in MOV between poor and non-poor in SSA. We used cross-sectional data from 35 Demographic and Health Surveys in SSA conducted between 2007 and 2016. Descriptive statistics used to understand the gap in MOV between the urban poor and non-poor, and across the selected covariates. Out of the 35 countries included in this analysis, 19 countries showed pro-poor inequality, 5 showed pro-non-poor inequality and remaining 11 countries showed no statistically significant inequality. Among the countries with statistically significant pro-illiterate inequality, the risk difference ranged from 4.2% in DR Congo to 20.1% in Kenya. Important factors responsible for the inequality varied across countries. In Madagascar, the largest contributors to inequality in MOV were media access, number of under-five children, and maternal education. However, in Liberia media access narrowed inequality in MOV between poor and non-poor households. The findings indicate that in most SSA countries, children belonging to poor households are most likely to have MOV and that socio-economic inequality in is determined not only by health system functions, but also by factors beyond the scope of health authorities and care delivery system. The findings suggest the need for addressing social determinants of health.

Mind the Gap: What explains the education-related inequality in missed opportunities for vaccination in sub-Saharan Africa? Compositional and structural characteristics.

Missed opportunities for vaccination (MOV) is an important barrier hindering full immunisation coverage among eligible children. Though factors responsible for MOV are well documented in literature, little attention has been paid to the role of inequalities. The aim of this study is to examine the association between structural or compositional factors and education inequalities in MOV. Blinder-Oaxaca decomposition technique was used to explain the factors contributing to the average gap in missed opportunities for vaccination between uneducated and educated mothers in sub-Saharan Africa using DHS survey data from 35 sub Saharan African countries collected between 2007 and 2016. The sample contained 69,657 children aged 12 to 23 months. We observed a wide variation and inter-country differences in the prevalence of missed opportunity for vaccination across populations and geographical locations. Our results show that the prevalence of MOV in Zimbabwe among uneducated and educated mothers was 9% and 21% respectively while in Gabon corresponding numbers were 85% and 89% respectively. In 15 countries, MOV was significantly prevalent among children born to uneducated mothers (pro-illiterate inequality) while in 5 countries MOV was significantly prevalent among educated mothers (pro-educated inequality). Our results suggest that education-related inequalities in missed opportunities for vaccination are explained by compositional and structural characteristics; and that neighbourhood socio-economic status was the most important contributor to education-related inequalities across countries followed by either the presence of under-five children, media access or household wealth index. The results showed that differential effects such as neighbourhood socio-economic status, presence of under-five children, media access and household wealth index, primarily explained education-related inequality in MOV. Interventions to reduce gaps in education-related inequality in MOV should focus on social determinants of health.