Introduction WHO recommends that all children receive one dose of bacille Calmette-Guerin vaccine (BCG), three doses of diphtheria--tetanus-pertussis vaccine (DTP), three doses of either oral polio vaccine (OPV) or inactivated polio vaccine (IPV), three doses of hepatitis B vaccine, and one dose of a measles virus-containing vaccine (MVCV), either anti-measles alone or in combination with other antigens (1-9) It also recommends three doses of vaccine against infection with Haemophilus influenzae type b (Hib) (10) To boost immunity at older ages, additional immunizations are recommended for healthcare workers, travellers, high-risk groups and people in areas where the risk of specific vaccine-preventable diseases is high (11) Immunization coverage levels and trends are used (i) to monitor the performance of immunization services locally, nationally and internationally; (ii) to guide strategies for the eradication, elimination and control of vaccine-preventable diseases; (12-14) (iii) to identify areas of immunization systems that may require additional resources and focused attention; (15,16) and (iv) to assess the need to introduce new vaccines into national and local immunization systems (17) Models of vaccine-preventable disease burden frequently include immunization coverage levels among their components (18-20) Coverage levels for measles vaccine and DTP are indicators of health system performance frequently considered by funding agencies when reviewing applications for financial and technical support (21-24) Measles immunization coverage is one of the indicators for tracking progress towards Millennium Development Goal 4, to reduce child mortality (25) Furthermore, trends in immunization coverage are used to establish the link between immunization service delivery and disease occurrence and to provide a framework for setting future coverage goals (26) Trends in immunization coverage While some countries had routine immunization systems in place before 1980, major national and international development of routine, universal infant immunization systems did not begin until the late 1970s In fact, it was not until the 1980s that dramatic improvements in immunization coverage were achieved, along with an increase in coverage with the third dose of DTP vaccine (DTP3) from 20% in 1980 to 75% coverage in 1990 While some countries reported significant declines in coverage after 1990, global coverage levels remained fairly constant and began rising slowly but steadily in 2000, until DTP3 coverage worldwide had reached 81% in 2006 In 1980, fewer than 10% of the world's children lived in 20 of the 167 countries with DTP3 coverage levels greater than 80%; 84% of the world's children lived in countries where coverage was less than 50% By 1990, 108 countries (43% of all children) had DTP3 coverage levels greater than 80%, and fewer than 10% of children lived in countries with under 50% coverage Although national coverage levels can "mask" sub-national geographical or sociological pockets where coverage is much lower, in 2006, 57% of children lived in countries with greater than 80% DTP3 coverage Still, that year approximately 263 million children who reached their first birthday did not receive DTP3, but 162 million (62%) of them lived in China, India, Indonesia or Nigeria At the time this report was prepared, there remained seven countries where fewer than half of the children were vaccinated with three doses of DTP3: Angola, Central African Republic, Chad, Equatorial Guinea, Gabon, Niger and Somalia" WHO and UNICEF publish annual estimates of national immunization coverage; (27-30) such estimates have been available by country since 1980 at http://wwwwhoint/immunization_monitoring/en/globalsummary/ wucoveragecountrylistcfm and http://wwwchildinfoorg/immunization_countryreportshtml Additional analyses can be found at http://wwwwhoint/immunization_monitoring/data/en/and http://www …

WHO and UNICEF Estimates of National Infant Immunization Coverage: Methods and processes/Estimations Par l'OMS et l'UNICEF Des Couvertures Vaccinales Des Nourrissons Par Pays : Methodes et procedures/Estimaciones De la OMS Y El UNICEF Sobre la Cobertura Nacional De Vacunacion De Los Lactantes: Metodos Y Procedimientos

Vaccines have made a major contribution to public health, including the eradication of one deadly disease, small pox, and the near eradication of another, poliomyelitis.Through the introduction of new vaccines, such as those against rotavirus and pneumococcal diseases, and with further improvements in coverage, vaccination can significantly contribute to the achievement of the health-related United Nations Millennium Development Goals.The Global Immunization Vision and Strategy (GIVS) was developed by WHO and UNICEF as a framework for strengthening national immunization programmes and protect as many people as possible against more diseases by expanding the reach of immunization, including new vaccines, to every eligible person.This paper briefly reviews global progress and challenges with respect to public vaccination programmes.

/pdf/global-immunization-status-progress-challenges-and-future-3quv7rmwgr.pdf

Global immunization: status, progress, challenges and future

Validity of vaccination cards and parental recall to estimate vaccination coverage: A systematic review of the literature

As in other areas of international development, we are witnessing the proliferation of ‘traveling models’ developed by international experts and introduced in an almost identical format across numerous countries to improve some aspect of maternal health systems in low- and middle-income countries. These policies and protocols are based on ‘miracle mechanisms’ that have been taken out of their original context but are believed to be intrinsically effective in light of their operational devices. In reality, standardised interventions are, in Africa and elsewhere, confronted with pragmatic implementation contexts that are always varied and specific, and which lead to drifts, distortions, dismemberments and bypasses. The partogram, focused antenatal care, the prevention of mother-to-child transmission of HIV or performance-based payment all illustrate these implementation gaps, often caused by the routine behaviour of health personnel who follow practical norms (and a professional culture) that are often distinct from official norms – as is the case with midwives. Experiences in maternal and child health in Africa suggest that an alternative approach would be to start with the daily reality of social and practical norms instead of relying on models, and to promote innovations that emerge from within local health systems.

/pdf/travelling-models-and-the-challenge-of-pragmatic-contexts-38qeyx0uv3.pdf

Travelling models and the challenge of pragmatic contexts and practical norms: the case of maternal health

Measuring routine childhood vaccination coverage in 204 countries and territories, 1980-2019: a systematic analysis for the Global Burden of Disease Study 2020, Release 1

Despite rapid and tangible progress in vaccine coverage and in premature mortality rates registered in sub-Saharan Africa, inequities to access remain firmly entrenched, large pockets of low vaccination coverage persist, and coverage often varies considerably across regions, districts, and health facilities' areas of responsibility. This paper focuses on system-related factors that can explain disparities in immunization coverage among districts in Burkina Faso. A multiple-case study was conducted of six districts representative of different immunization trends and overall performance. A participative process that involved local experts and key actors led to a focus on key factors that could possibly determine the efficiency and efficacy of district vaccination services: occurrence of disease outbreaks and immunization days, overall district management performance, resources available for vaccination services, and institutional elements. The methodology, geared toward reconstructing the evolution of vaccine services performance from 2000 to 2006, is based on data from documents and from individual and group interviews in each of the six health districts. The process of interpreting results brought together the field personnel and the research team. The districts that perform best are those that assemble a set of favourable conditions. However, the leadership of the district medical officer (DMO) appears to be the main conduit and the rallying point for these conditions. Typically, strong leadership that is recognized by the field teams ensures smooth operation of the vaccination services, promotes the emergence of new initiatives and offers some protection against risks related to outbreaks of epidemics or supplementary activities that can hinder routine functioning. The same is true for the ability of nurse managers and their teams to cope with new situations (epidemics, shortages of certain stocks). The discourse on factors that determine the performance or breakdown of local health care systems in lower and middle income countries remains largely concentrated on technocratic and financial considerations, targeting institutional reforms, availability of resources, or accessibility of health services. The leadership role of those responsible for the district, and more broadly, of those we label "the human factor", in the performance of local health care systems is mentioned only marginally. This study shows that strong and committed leadership promotes an effective mobilization of teams and creates the conditions for good performance in districts, even when they have only limited access to supports provided by external partners. See the full article online for a translation of this abstract in French.

/pdf/system-level-determinants-of-immunization-coverage-37w7iathth.pdf

System-level determinants of immunization coverage disparities among health districts in Burkina Faso : a multiple case study

Background Data aggregation in national information systems begins at the district level. Decentralization has given districts a lead role in health planning and management, therefore validity of administrative-based estimates at that level is important to improve the performance of immunization information systems.

Objective To assess the validity of administrative-based immunization estimates and their usability for planning and monitoring activities at district level.

Methods DTP3 and measles coverage rates from administrative sources were compared with estimates from the EPI cluster survey (ECS) and Demographic and Health Survey (DHS) carried out in 2003 at national and regional levels. ECS estimates were compared with administrative rates across the 52 districts, which were classified into three groups: those where administrative rates were underestimating, overestimating or concordant with ECS estimates (differences within 95% CI of ECS rate).

Results National rates provided by administrative data and ECS are similar (74% and 71% for DTP3 and 68% and 66% for measles, respectively); DHS estimates are much lower. Regional administrative data show large discrepancies when compared against ECS and DHS data (differences sometimes reaching 30 percentage points). At district level, geographical area is correlated with over- or underestimation by administrative sources, which overestimate DTP3 and measles coverage in remote areas. Underestimation is observed in districts near urban and highly populated centres. Over- and underestimation are independent of the antigen under consideration.

Conclusions Variability in immunization coverage across districts highlights the limitations of using nationally aggregated indicators. If district data are to be used in monitoring and planning immunization programmes as intended by decentralization, heterogeneity in their validity must be reduced. The authors recommend: (1) strengthening administrative data systems; (2) implementing indicators that are insensitive to population mobility; (3) integrating surveys into monitoring processes at the subnational level; (4) actively promoting the use of coverage information by local personnel and district-level staff.

Heterogeneity in the validity of administrative-based estimates of immunization coverage across health districts in Burkina Faso: implications for measurement, monitoring and planning.

The greatest challenge facing expanded programs on immunization in general, and in Burkina Faso in particular, lies in their capacity to achieve and sustain levels of immunization coverage that will ensure effective protection of children. This article aims to demonstrate that full immunization coverage of children, which is the primary indicator for monitoring national immunization programs, is sufficient neither to evaluate their performance adequately, nor to help identify the broad strategies that must be implemented to improve their performance. Other dimensions of performance, notably adherence to the vaccination schedule and the efficacy of the approaches used to reach all the children (targeting) must also be considered. The study was carried out using data from surveys carried out in Burkina Faso: the 1993, 1998 and 2003 Demographic and Health Surveys and the 2003 national Survey of Immunization Coverage. Essentially, we described levels of immunization coverage and their trends according to the indicators considered. Performance differences are illustrated by amplitudes and maximum/minimum ratios. The health regions' performances vary according to whether they are evaluated on the basis of full immunization coverage or vaccination status of children who have not completed their vaccinations. The health regions encompass a variety of realities, and efforts of substantially different intensity would be required to reach all the target populations. Decision-making can be improved by integrating a tripartite view of performance that includes full immunization coverage, adherence to the vaccination schedule (timely coverage), and the status of children who are not fully vaccinated. With such an approach, interventions can be better targeted. It provides information on the quality and timeliness of vaccination and identifies the efforts required to meet the objectives of full immunization coverage. See the full article online for a translation of this abstract in French.

/pdf/monitoring-the-performance-of-the-expanded-program-on-17u7kwbhy9.pdf

Marta Feletto

Papers

System-level determinants of immunization coverage disparities among health districts in Burkina Faso : a multiple case study

Heterogeneity in the validity of administrative-based estimates of immunization coverage across health districts in Burkina Faso: implications for measurement, monitoring and planning.

Monitoring the performance of the Expanded Program on Immunization: the case of Burkina Faso