Background: Vitamin A deficiency remains a major public health problem in high‑mortality settings, yet vitamin A supplementation (VAS) coverage in many countries remains below global targets. Although women’s empowerment is increasingly recognised as an important determinant of child health behaviours, its influence on VAS uptake has not been well characterised. We assessed how multiple dimensions of maternal empowerment, alongside household and child factors, are associated with VAS coverage. Methods: We pooled the most recent Demographic and Health Surveys (2015–2024/25) from 28 Sub‑Saharan African countries, including 275,363 children aged 6–59 months. The outcome was caregiver‑reported or card‑verified receipt of VAS in the preceding 6 months. We fitted multilevel mixed‑effects logistic regression models with random intercepts for country and primary sampling unit. Maternal characteristics included education, age, marital status, and four empowerment dimensions: media access, asset ownership, decision‑making autonomy, and attitudes toward intimate partner violence. Child age and sex and household wealth and residence were also included. Findings: Weighted VAS coverage was 48·4%, ranging from 17·9% in Senegal to 86·1% in Rwanda. Maternal education showed a clear gradient: compared with no education, adjusted odds ratios (aORs) were 1·19 for primary, 1·34 for secondary, and 1·54 for higher education. Mothers aged 15–19 years had lower odds of children receiving VAS (aOR 0·73) than those aged 20–24 years, whereas older mothers had higher odds (aORs 1·15–1·30). Higher maternal asset ownership (aORs 1·31–1·58) and media access (aOR 0·89 for none) were strongly associated with VAS uptake. Interpretation: VAS coverage across 28 Sub‑Saharan African countries remains low and largely unchanged since 2013. Enhancing women’s access to information and resources, addressing socioeconomic barriers, and reducing early childbearing are critical to improving and sustaining VAS coverage.

Background:Women's mental health remains critically under-researched in Bangladesh, despite its close links with gender inequality. In this study, we examined how three domains of women's empowerment - attitudes to violence, social independence, and decision-making - are associated with mental health outcomes among currently married women in Bangladesh. Methods:Using nationally representative data from the 2022 Bangladesh Demographic and Health Survey, we analysed 18 900 currently married women. We assessed women's empowerment using the survey-based women's empowerment index, which was categorised as low, medium, or high. Depression and anxiety were measured using the Patient Health Questionnaire-9 and the Generalised Anxiety Disorder-7, respectively. We applied multivariable logistic regression models, adjusting for key sociodemographic covariates. Results:Overall, 4.6% women reported depression, and 4.0% reported anxiety. Women with low empowerment in attitude to violence domain had higher odds of depression (adjusted odds ratio (aOR) = 1.48; 95% confidence interval (CI) = 1.17-1.86) and anxiety (aOR = 1.41; 95% CI = 1.09-1.82), compared to women with high empowerment. In the social independence domain, low empowerment was significantly associated with anxiety (aOR = 1.28; 95% CI = 1.02-1.60) but not with depression. Low empowerment in the decision-making domain was not associated with depressive or anxiety symptoms; however, it was associated with lower odds of severe depressive (aOR = 0.48; 95% CI = 0.33-0.70) and anxiety symptoms (aOR = 0.44; 95% CI = 0.28-0.71) when the outcome was disaggregated by severity. Conclusions:Women's empowerment is associated with mental health in Bangladesh. Structural interventions must integrate gender-transformative approaches that challenge discriminatory norms and promote women's social standing, reinforcing the interconnection between Sustainable Development Goal three (good health and well-being) and five (gender equality).

ObjectivesVitamin A deficiency affects an estimated 29% of all children under 5 years of age in low/middle-income countries, contributing to child mortality and exacerbating severity of infections. Biannual vitamin A supplementation (VAS) for children aged 6-59 months can be a low-cost intervention to meet vitamin A needs. This study aimed to present a framework for evaluating the equity dimensions of national VAS programmes according to determinants known to affect child nutrition and assist programming by highlighting geographical variation in coverage.MethodsWe used open-source data from the Demographic and Health Survey for 49 countries to identify differences in VAS coverage between subpopulations characterised by various immediate, underlying and enabling determinants of vitamin A status and geographically. This included recent consumption of vitamin A-rich foods, access to health systems and services, administrative region of the country, place of residence (rural vs urban), socioeconomic position, caregiver educational attainment and caregiver empowerment.ResultsChildren who did not recently consume vitamin A-rich foods and who had poorer access to health systems and services were less likely to receive VAS in most countries despite potentially having a greater vitamin A need. Differences in coverage were also observed when disaggregated by administrative regions (88% of countries) and urban versus rural residence (35% of countries). Differences in vitamin A coverage between subpopulations characterised by other determinants of vitamin A status varied considerably between countries.ConclusionVAS programmes are unable to reach all eligible infants and children, and subpopulation differences in VAS coverage characterised by various determinants of vitamin A status suggest that VAS programmes may not be operating equitably in many countries.

Vaccines and vitamin A supplementation (VAS) are financed by donors in several countries, indicating that challenges remain with achieving sustainable government financing of these critical health commodities. This qualitative study aimed to explore political economy variables of actors' interests, roles, power and commitment to ensure government financing of vaccines and VAS. A total of 77 interviews were conducted in Burundi, Comoros, Ethiopia, Madagascar, Malawi and Zimbabwe. Governments and development partners had similar interests. Donor commitment to vaccines and VAS was sometimes dependent on the priorities and political situation of the donor country. Governments' commitment to financing vaccines was demonstrated through policy measures, such as enactment of immunization laws. Explicit government financial commitment to VAS was absent in all six countries. Some development partners were able to influence governments directly via allocation of health funding while others influenced indirectly through coordination, consolidation and networks. Government power was exercised through multiple systemic and individual processes, including hierarchy, bureaucracy in governance and budgetary process, proactiveness of Ministry of Health officials in engaging with Ministry of Finance, and control over resources. Enablers that were likely to increase government commitment to financing vaccines and VAS included emerging reforms, attention to the voice of citizens and improvements in the domestic economy that in turn increased government revenues. Barriers identified were political instability, health sector inefficiencies, overly complicated bureaucracy, frequent changes of health sector leadership and non-health competing needs. Country governments were aware of their role in financing vaccines, but only a few had made tangible efforts to increase government financing. Discussions on government financing of VAS were absent. Development partners continue to influence government health commodity financing decisions. The political economy environment and contextual factors work together to facilitate or impede domestic financing.

Abstract Child stunting prevalence is primarily used as an indicator of impeded physical growth due to undernutrition and infections, which also increases the risk of mortality, morbidity and cognitive problems, particularly when occurring during the 1000 days from conception to age 2 years. This paper estimated the relationship between stunting prevalence and age for children 0–59 months old in 94 low‐ and middle‐income countries. The overall stunting prevalence was 32%. We found higher stunting prevalence among older children until around 28 months of age—presumably from longer exposure times and accumulation of adverse exposures to undernutrition and infections. In most countries, the stunting prevalence was lower for older children after around 28 months—presumably mostly due to further adverse exposures being less detrimental for older children, and catch‐up growth. The age for which stunting prevalence was the highest was fairly consistent across countries. Stunting prevalence and gradient of the rise in stunting prevalence by age varied across world regions, countries, living standards and sex. Poorer countries and households had a higher prevalence at all ages and a sharper positive age gradient before age 2. Boys had higher stunting prevalence but had peak stunting prevalence at lower ages than girls. Stunting prevalence was similar for boys and girls after around age 45 months. These results suggest that programmes to prevent undernutrition and infections should focus on younger children to optimise impact in reducing stunting prevalence. Importantly, however, since some catch‐up growth may be achieved after age 2, screening around this time can be beneficial.

Background Wasting reflects infections and poor nutrition and affects almost 50 million children at any given time. Wasting comes with immediate risk of mortality and increased risks for long-term negative consequences for development. Children under two are particularly sensitive to undernutrition and infections. We estimated the age patterning in wasting prevalence. Methods We calculated wasting prevalence and used Poisson regression models to estimate prevalence ratios comparing prevalence in children under and over two years using data from Demographic and Health Surveys and Multiple Indicator Cluster Surveys from 94 mostly low- and middle-income countries, including 804,172 children under five, born to a nationally representative sample of women 15-49 years old. Wasting prevalence was defined as the percentage of children with weight-for-height below -2 z-score from the median of the WHO 2006 growth standard. Findings Wasting prevalence for children under two was 14% (95% CI: 13, 14) while it was 9% (95% CI: 9, 9) for children 2-4 years old-leading to a prevalence ratio of 0.66 (95% CI: 0.64, 0.67) in our pooled sample. Prevalence ratios were less than one, indicating lower prevalence in children over two, in 87 countries and statistically significantly lower than one at a 5% level (non-adjusted) in 68 countries. Wasting prevalence was generally lower in children under two for males and females and the wealthiest and poorest households. Interpretation Since wasting prevalence was observed to be greater among children 0-2 years, and adverse exposure to undernutrition and infections are particularly harmful and interventions are more effective during the 1000 days from conception until age two, nutrition interventions should ensure coverage of children under two through programmatic measures to increase detection and enrollment in wasting programs. Copyright (C) 2022 The Authors. Published by Elsevier Ltd.

Key Points Question What share of deaths among children younger than 5 years occur before 2 years of age in low- and middle-income countries? Findings In this cross-sectional study of 2 827 515 children younger than 5 years from 77 countries, a large majority (81.5%) of deaths occurred before 2 years of age in all countries, among boys and girls, and in the households with the highest and lowest living standards. Meaning These findings suggest that coverage of potentially life-saving interventions should be ensured for children younger than 2 years of age in low- and middle-income countries.

Gausman et al1 argue that multiple measures of anthropometric failure (AF) are needed to assess undernutrition in the country context and design public health and nutrition programs to reach the most economically disadvantaged children younger than 5 years. But in practice, how can programs use information on AF to improve delivery of crucial interventions? Anthropometric failure is a collective label for stunting (height-for-age), wasting (weight-for-height), and underweight (weight-for-age) outcomes, which serve as proxies for undernutrition in the absence of nutritional intake data. Although wasting and underweight are caused by both short-term and long-term nutritional insufficiency as well as disease, usually stunting does not result from short-term insufficiency. Gausman et al1 used Demographic and Health Survey (DHS) data from 56 lowand middleincome countries to compare different measures of AF. Their analysis looks at the 3 conventional measures of AF (stunting, underweight, and wasting rates); an alternative classification system called the Composite Index of Anthropometric Failure (CIAF), which aggregates the 3 conventional measures into a single indicator; and a disaggregated measure entitled Categories of Anthropometric Failure (CAF) that quantifies the proportion of children who have combinations of the 3 conventional measures. The CAF looks at the disease burden from 3 combinations of AFs: stunting, wasting, and underweight, stunting and underweight, and wasting and underweight. A fourth combination, stunting and wasting without underweight, is not possible. Stunting only, wasting only, and underweight only are also theoretical options. Because the mortality impact is clearest in the stunting, wasting, and underweight group, this indicator could be a primary focus for nutrition and health programs. The analysis found significant differences in estimates of children with undernutrition depending on the choice of measure. Substantial overlap between the 3 conventional measures suggests that children may experience 1 or multiple failures at different times in their lives. Focusing on overall prevalence of stunting, underweight, and wasting only, without disaggregation, risks neglecting children with coinciding AFs. The children with simultaneous AFs are obviously more disadvantaged and have increased risk of poor health outcomes (evidence suggests that at least coinciding stunting, wasting, and underweight increases mortality).2 These children are also likely to be the hardest for programs to reach. The analysis did not stratify by age or sex, and it would be interesting to explore whether younger children (eg, 6-11 or 6-23 months) have a different profile than older children and whether there are differences between girls and boys. Nevertheless, more information on the association between multiple, concurrent failures (as defined by the CAF and other measures) will help public health and nutrition program managers address inequities in delivery and contribute toward global goals, such as the United Nations’ Sustainable Development Goal (SDG) Target 2.2, which seeks to end all forms of malnutrition by 2030. How can information on CAF combinations inform the way health and nutrition programs are delivered? The study findings suggest Niger as an example of a country with a large proportion of the overall burden of AFs (7.5%) is owing to coinciding stunting, wasting, and underweight. This contrasts with bordering Benin, which has a similar overall CIAF burden (57.1% in Benin and 56.0% in Niger) but only half the rate of stunting, wasting, and underweight (around 3.6%). Benin instead has a larger burden of stunting only, about 29% compared with Niger’s 15.7%. Sex differences might explain some of this variation. Similarly, Burkina Faso and Guatemala both have a CIAF of 47.3%, but + Related article

Correspondence to Dr Andreas Hasman; ahasman@ unicef. org © Author(s) (or their employer(s)) 2021. Reuse permitted under CC BYNC. No commercial reuse. See rights and permissions. Published by BMJ. In efforts to restrict the spread of SARSCoV2, many lowincome and middleincome countries suspended communitybased public health and nutrition programmes in early 2020. At the time, the expectation was that disruptions due to the COVID19 response would cause significant declines in programme coverage of key services, and eventually increase preventable morbidity and mortality among the most vulnerable children. The magnitude of the pandemic’s impact on preventive vitamin A supplementation (VAS) programmes is now made visible in UNICEF’s annual programme coverage data. Regular administration of highdose VAS to children 6–59 months old every 4–6 months reduces the risk of child mortality by 12%–24% in communities where vitamin A deficiency is prevalent. Prior to the pandemic, the global VAS programme reached over 200 million children annually with the recommended two VAS doses in countries with high child mortality. Between 2016 and 2019, coverage had been hovering at around 65% of eligible children. In the year prior to the COVID19 outbreak, about 200 million eligible children benefited from the two annual doses of VAS, while 134 million missed out on at least one of the doses and therefore the full benefits of supplementation. The situation deteriorated sharply following the March COVID19 outbreak, primarily due to service delivery disruptions caused by pandemic containment measures. Based on administrative data analysed by UNICEF, there was a 19 percentage point decline in twodose VAS coverage from 2019 (from 60% to 41%; figure 1), with 62 million fewer children (ie, onethird) receiving both VAS doses in 2020. The steepest drops in coverage occurred in the first half of the year (figure 2) following recommendations to suspend mass public health and nutrition campaigns. Global VAS coverage thus fell from 72% in the first half of 2019 to 49% in the first half of 2020, while the number of children covered fell from 239 million in the first half of 2019 to 165 million in the first half of 2020 (ie, a drop of almost a quarter). In the second half of 2020, when suspensions were rescinded, 57% or 192 million eligible children were reached compared with 63% or 211 million children in the second half of 2019 (a drop of only six percentage points). Eight countries drove the sharp decline in twodose coverage in 2020: Afghanistan, Cameroon, Chad, Niger, Nigeria, Pakistan, Sudan and Tanzania. In these countries, 85 million children were missed (ie, 43% of the total number of missed children). If the eight countries were to regain the coverage achieved in 2019, global VAS coverage would be 61%. Arguably, they should be given priority attention to shore up the coverage of the global VAS programme. It is also clear that countries with the greatest need for supplementation, that is, highest child mortality, had the lowest coverage in 2020. Out of the 48 countries from which we have data, 23 have under5 Summary box

Countries are increasingly transitioning from event-based vitamin A supplementation (VAS) distribution to delivery through routine health system contacts, shifting also to administrative, electronic-based monitoring tools, a process that brings certain limitations affecting the quality of administrative VAS coverage. At present, there is no standardised methodology for measuring the coverage of VAS delivered through routine health services. To address this gap, we conducted a systematic review of the literature to identify and recommend methods to measure VAS coverage, with the aim of providing guidance to countries on the collection of consistent data for planning, monitoring and evaluating VAS programmes integrated into routine health systems. We searched the PubMed®, Embase®, Scopus, Google Scholar and World Health Organization (WHO) Global Index Medicus databases for studies published from 1 January 2000 to 1 January 2021, reporting original data on VAS coverage and methodologies used for measurement. We screened 2371 original titles and abstracts, assessed twenty-seven full-text articles and ultimately included eighteen studies. All but two studies used a coverage cluster survey (CCS) design to measure VAS coverage, adapting the WHO Vaccination Coverage Cluster Surveys methodology, by modifying sample size and sampling parameters. Annual two-dose VAS coverage was reported from only four studies. Until electronic-based systems to collect and analyse VAS data are equipped to measure routine two-dose VAS coverage using administrative data, CCSs that comply with the 2018 WHO Vaccination Coverage Cluster Surveys Reference Manual represent the gold-standard method for effective VAS programme monitoring.

UNICEF operates in 190 countries and territories, where it advocates for the protection of children’s rights and helps meet children’s basic needs to reach their full potential. Embedded implementation research (IR) is an approach to health systems strengthening in which (a) generation and use of research is led by decision-makers and implementers; (b) local context, priorities, and system complexity are taken into account; and (c) research is an integrated and systematic part of decision-making and implementation. By addressing research questions of direct relevance to programs, embedded IR increases the likelihood of evidence-informed policies and programs, with the ultimate goal of improving child health and nutrition. This paper presents UNICEF’s embedded IR approach, describes its application to challenges and lessons learned, and considers implications for future work. From 2015, UNICEF has collaborated with global development partners (e.g. WHO, USAID), governments and research institutions to conduct embedded IR studies in over 25 high burden countries. These studies focused on a variety of programs, including immunization, prevention of mother-to-child transmission of HIV, birth registration, nutrition, and newborn and child health services in emergency settings. The studies also used a variety of methods, including quantitative, qualitative and mixed-methods. UNICEF has found that this systematically embedding research in programs to identify implementation barriers can address concerns of implementers in country programs and support action to improve implementation. In addition, it can be used to test innovations, in particular applicability of approaches for introduction and scaling of programs across different contexts (e.g., geographic, political, physical environment, social, economic, etc.). UNICEF aims to generate evidence as to what implementation strategies will lead to more effective programs and better outcomes for children, accounting for local context and complexity, and as prioritized by local service providers. The adaptation of implementation research theory and practice within a large, multi-sectoral program has shown positive results in UNICEF-supported programs for children and taking them to scale.

Background Embedded implementation research (IR) can play a critical role in health systems strengthening by tackling systems and implementation bottlenecks of a program. To achieve this aim, with the financial support of GAVI, the Vaccine Alliance, in 2016, the Government of Pakistan, UNICEF and the Alliance for Health Policy and Systems Research (AHPSR) launched an Embedded IR for Immunisation Initiative (the Initiative) to explore health systems and implementation bottlenecks, and potential strategies to tackle such bottlenecks in the Expanded Programme on Immunisation (EPI) in Pakistan. In total, 10 research teams were involved in the Initiative, which was the first of its kind in the country. In this paper, we provided a brief overview of the Initiative's approach as well as the key learnings including challenges and successes of the research teams which could inform future embedded IR Initiatives. Methods Data were collected from members of the IR teams through an online survey. In addition, in-depth interviews were conducted via phone and in-person from IR team members to explore further the challenges they faced while conducting IR in Pakistan and recommendations for future IR initiatives. The qualitative information obtained from these sources was collated and categorized into themes reflecting some of the challenges, successes, and lessons learned, as well as teams' recommendations for future initiatives. Results The embedded IR Initiative in Pakistan followed several steps starting with a desk review to compile information on key implementation challenges of EPI and ended with a dissemination workshop where all the research teams shared their IR results with policymakers and implementers. Key factors that facilitated the successful and timely completion of the studies included appreciation by and leadership of implementers in generation and use of local knowledge, identification of research priorities jointly by EPI managers and researchers and provision of continuous and high-quality support from in-country research partners. Participants in the Initiative indicated that challenges included a lack of clarity on the role and responsibilities of each partner involved and need for further support to facilitate use and dissemination of research findings. Conclusions The Initiative established that an immunisation programme in a lower middle-income country can use small and time-bound embedded IR, based on partnerships between programme managers and local researchers, to generate information and evidence that can inform decision-making. Future embedded IR initiatives should strive to ensure effective coordination and active participation of all key stakeholders, a clear research utilisation plan from the outset, and efforts to strengthen research teams' capacity to foster utilisation of research findings.

Background Embedded implementation research (IR) promotes evidence-informed policy and practices by involving decision-makers and program implementers in research activities that focus on understanding and solving existing implementation challenges. Although embedded IR has been conducted in multiple settings by different organizations, there are limited experiences of embedded IR in humanitarian settings. This study highlights some of the key challenges of conducting embedded IR in a humanitarian setting based on our experience with the Rohingya refugee population in Cox’s Bazar, Bangladesh. Methods and findings We collected qualitative data in between January and July 2019. First, we visited Rohingya refugee camps and interviewed representatives from different humanitarian organizations. Second, we conducted interviews with researchers from BRAC University who were engaged with data collection and analysis in a broader embedded IR study on maternal, newborn, child, and adolescent health (MNCAH) program implementation challenges. Data were analyzed using a thematic analysis approach. Two researchers developed and agreed on codes and relevant themes based on the objectives of this study. The findings of this study highlight several challenges encountered while conducting embedded IR in the Rohingya emergency setting in Cox’s Bazar, which may have implications for other humanitarian settings. The overall context of the camps was complex, with more than 100 organizations devoted to providing health services for approximately 1 million refugees. Despite the presence of the Bangladesh government, United Nations agencies and other international organizations played key roles in making programmatic and policy decisions for the Rohingya. Because health service delivery modalities and policies and related implementation challenges for MNCAH programs for the refugees changed rapidly, the embedded IR approach used was flexible and able to adapt to changes identified, with research questions and methods modified accordingly. Access to the camps, reaching Rohingya respondents, overcoming language barriers in order to get quality information, and the limited availability of local research collaborators were additional challenges. Working with researchers or research institutes that are familiar with the context and have experience in conducting implementation and health systems research can help with collection of quality data, identifying key stakeholders and bringing them on board to ensure the execution of the project, and ensuring utilization of the research findings. Study limitations include possible constraints in generalizing our conclusions to other humanitarian settings. Implementation research conducted in additional humanitarian settings can contribute to the evidence on this topic. Conclusions Findings indicate that embedded IR can be done effectively in humanitarian settings if the challenges are anticipated, and appropriate strategies and in-country partners put in place to address or mitigate them, before commencing the funding or starting of the project. Understanding the context and analyzing the role of relevant stakeholders prior to conducting the research, considering a simple descriptive method appropriate to answering real-time IR questions, and working with local researchers or research institutes with specific skill sets and prior experience conducting research in humanization contexts may reduce costs and time spent, and ensure collection of quality data relevant for policy and practice.

Background During August 2017 January 2018, more than 700,000 forcibly displaced Rohingyas crossed into Cox's Bazar, Bangladesh. In response to measles and diphtheria cases, first documented in September and November 2017, respectively, vaccination campaigns targeting children <15 years old were mobilized during September 2017 March 2018. However, in a rapidly evolving emergency situation, poor sanitation, malnutrition, overcrowding, and lack of access to safe water and healthcare can increase susceptibility to infectious diseases, particularly among children. We aimed to estimate population immunity to vaccine preventable diseases (VPDs) after vaccination activities in the camps to identify any remaining immunity gaps among Rohingya children. Methods and findings We conducted a cross-sectional serologic and vaccination coverage survey in Nayapara Registered Refugee Camp ("Nayapara") and makeshift settlements (MSs) April 28, 2018 to May 31, 2018, among 930 children aged 6 months to 14 years. MSs are informal, self-settled areas with a population of more than 850,000, the majority of whom arrived after August 2017, whereas Nayapara is a registered camp and has better infrastructure than MSs, including provision of routine immunization services. Households were identified using simple random sampling (SRS) in Nayapara and multistage cluster sampling in MSs (because household lists were unavailable). Dried blood spots (DBSs) were collected to estimate seroprotection against measles, rubella, diphtheria, and tetanus, using Luminex multiplex bead assay (MBA). Caregiver interviews assessed vaccination campaign participation using vaccination card or recall. In Nayapara, 273 children aged 1 to 6 years participated; 46% were female and 88% were registered refugees. In MSs, 358 children aged 1 to 6 years and 299 children aged 7 to 14 years participated; 48% of all children in MSs were female, and none were registered refugees. In Nayapara, estimated seroprotection among 1- to 6-year-olds was high for measles, rubella, diphtheria, and tetanus (91%-98%; 95% confidence interval [CI] 87%-99%); children >6 years were not assessed. In MSs, measles seroprotection was similarly high among 1- to 6-year-olds and 7- to 14-year-olds (91% [95% CI 86%-94%] and 99% [95% CI 96%-100%], respectively, p < 0.001). Rubella and diphtheria seroprotection in MSs were significantly lower among 1- to 6-year-olds (84% [95% CI 79%-88%] and 63% [95% CI 56%-70%]) compared to 7- to 14-year-olds (96% [95% CI 90%-98%] and 77% [95% CI 69%-84%]) (p < 0.001). Tetanus seroprevalence was similar among 1- to 6-year-olds and 7- to 14-year-olds (76% [95% CI 69%-81%] and 84% [95% CI 77%-89%], respectively; p = 0.07). Vaccination campaign coverage was consistent with seroprotection in both camps. However, nonresponse, the main limitation of the study, may have biased the seroprotection and campaign coverage results. Conclusions In this study, we observed that despite multiple vaccination campaigns, immunity gaps exist among children in MSs, particularly for diphtheria, which requires serial vaccinations to achieve maximum protection. Therefore, an additional tetanus-diphtheria campaign may be warranted in MSs to address these remaining immunity gaps. Rapid scale-up and strengthening of routine immunization services to reach children and to deliver missed doses to older children is also critically needed to close immunity gaps and prevent future outbreaks.

The Global Polio Eradication Initiative has reduced the global incidence of polio by 99% and the number of countries with endemic polio from 125 to 3 countries. The Polio Eradication and Endgame Strategic Plan 2013-2018 (Endgame Plan) was developed to end polio disease. Key elements of the endgame plan include strengthening immunization systems using polio assets, introducing inactivated polio vaccine (IPV), and replacing trivalent oral polio vaccine with bivalent oral polio vaccine ("the switch"). Although coverage in the Eastern Mediterranean Region (EMR) with the third dose of a vaccine containing diphtheria, tetanus, and pertussis antigens (DTP3) was ≥90% in 14 countries in 2015, DTP3 coverage in EMR dropped from 86% in 2010 to 80% in 2015 due to civil disorder in multiple countries. To strengthen their immunization systems, Pakistan, Afghanistan, and Somalia developed draft plans to integrate Polio Eradication Initiative assets, staff, structure, and activities with their Expanded Programmes on Immunization, particularly in high-risk districts and regions. Between 2014 and 2016, 11 EMR countries introduced IPV in their routine immunization program, including all of the countries at highest risk for polio transmission (Afghanistan, Pakistan, Somalia, and Yemen). As a result, by the end of 2016 all EMR countries were using IPV except Egypt, where introduction of IPV was delayed by a global shortage. The switch was successfully implemented in EMR due to the motivation, engagement, and cooperation of immunization staff and decision makers across all national levels. Moreover, the switch succeeded because of the ability of even the immunization systems operating under hardship conditions of conflict to absorb the switch activities.

This analysis describes an innovative and successful approach to risk identification and mitigation in relation to the switch from trivalent to bivalent oral polio vaccine (OPV) in the 11 countries of the World Health Organization's (WHO's) South-East Asia Region (SEAR) in April 2016.The strong commitment of governments and immunization professionals to polio eradication and an exemplary partnership between the WHO, United Nations Children's Fund (UNICEF), and other partners and stakeholders in the region and globally were significant contributors to the success of the OPV switch in the SEAR. Robust national switch plans were developed and country-specific innovations were planned and implemented by the country teams. Close monitoring and tracking of the activities and milestones through dashboards and review meetings were undertaken at the regional level to ensure that implementation time lines were met, barriers identified, and solutions for overcoming challenges were discussed and implemented.The SEAR was the first WHO Region globally to complete the switch and declare the successful withdrawal of trivalent OPV from all countries on 17 May 2016.A number of activities implemented during the switch process are likely to contribute positively to existing immunization practices and to similar initiatives in the future. These activities include better vaccine supply chain management, improved mechanisms for disposal of vaccination-related waste materials, and a closer collaboration with drug regulators, vaccine manufacturers, and the private sector for immunization-related initiatives.

Nine polio areas of expertise were applied to broader immunization and mother, newborn and child health goals in ten focus countries of the Polio Eradication Endgame Strategic Plan: policy & strategy development, planning, management and oversight (accountability framework), implementation & service delivery, monitoring, communications & community engagement, disease surveillance & data analysis, technical quality & capacity building, and partnerships. Although coverage improvements depend on multiple factors and increased coverage cannot be attributed to the use of polio assets alone, 6 out of the 10 focus countries improved coverage in three doses of diphtheria tetanus pertussis containing vaccine between 2013 and 2015. Government leadership, evidence-based programming, country-driven comprehensive operational annual plans, community partnership and strong accountability systems are critical for all programs and polio eradication has illustrated these can be leveraged to increase immunization coverage and equity and enhance global health security in the focus countries.