A life-course approach to health: synergy with sustainable development goals.

A life-course approach to health encompasses strategies across individuals' lives that optimize their functional ability (taking into account the interdependence of individual, social, environmental, temporal and intergenerational factors), thereby enabling well-being and the realization of rights. The approach is a perfect fit with efforts to achieve universal health coverage and meet the sustainable development goals (SDGs). Properly applied, a life-course approach can increase the effectiveness of the former and help realize the vision of the latter, especially in ensuring health and well-being for all at all ages. Its implementation requires a shared understanding by individuals and societies of how health is shaped by multiple factors throughout life and across generations. Most studies have focused on noncommunicable disease and ageing populations in high-income countries and on epidemiological, theoretical and clinical issues. The aim of this article is to show how the life-course approach to health can be extended to all age groups, health topics and countries by building on a synthesis of existing scientific evidence, experience in different countries and advances in health strategies and programmes. A conceptual framework for the approach is presented along with implications for implementation in the areas of: (i) policy and investment; (ii) health services and systems; (iii) local, multisectoral and multistakeholder action; and (iv) measurement, monitoring and research. The SDGs provide a unique context for applying a holistic, multisectoral approach to achieving transformative outcomes for people, prosperity and the environment. A life-course approach can reinforce these efforts, particularly given its emphasis on rights and equity.

Une approche sanitaire fondée sur le parcours de vie englobe des stratégies tout au long de la vie des individus qui optimisent leur capacité fonctionnelle (en prenant en compte l'interdépendance de facteurs individuels, sociaux, environnementaux, temporels et intergénérationnels), assurant ainsi le bien-être et l'exercice des droits. Cette approche s'inscrit parfaitement dans les efforts déployés pour parvenir à une couverture sanitaire universelle et atteindre les objectifs de développement durable (ODD). Lorsqu'elle est correctement appliquée, une approche fondée sur le parcours de vie peut accroître l'efficacité de la première et aider à concrétiser l'ambition des seconds, en assurant notamment la santé et le bien-être pour tous à tous les âges. Sa mise en œuvre exige une compréhension commune par les individus et les sociétés de la manière dont la santé est façonnée par de multiples facteurs tout au long de la vie et d'une génération à l'autre. La plupart des études réalisées ont porté sur des maladies non transmissibles et le vieillissement des populations dans les pays à revenu élevé, ainsi que sur des aspects épidémiologiques, théoriques et cliniques. L'objectif de cet article est de montrer que l'approche sanitaire fondée sur le parcours de vie peut être élargie à toutes les tranches d'âge, toutes les questions de santé et tous les pays en s'appuyant sur une synthèse des données scientifiques existantes, les expériences de différents pays et l'avancement des stratégies et programmes en matière de santé. Un cadre conceptuel de l'approche est présenté ainsi que les conséquences de sa mise en œuvre sur: (i) la politique et l'investissement; (ii) les services et systèmes de santé; (iii) les actions locales, multisectorielles et multipartites; et (iv) les mesures, la surveillance et la recherche. Les ODD fournissent un contexte unique pour l'application d'une approche globale et multisectorielle en vue d'obtenir des résultats porteurs de transformation pour les individus, la prospérité et l'environnement. Une approche fondée sur le parcours de vie peut renforcer ces efforts, notamment parce qu'elle met l'accent sur les droits et l'équité.

Un enfoque basado en la salud para toda la vida engloba estrategias durante la vida de las personas, que optimizan su capacidad funcional (teniendo en cuenta la interdependencia de los factores individuales, sociales, ambientales, temporales e intergeneracionales), permitiendo así el bienestar y la realización de los derechos. El enfoque encaja perfectamente con los esfuerzos por lograr una cobertura sanitaria universal y cumplir los objetivos de desarrollo sostenible (ODS). Si se aplica correctamente, un enfoque para toda la vida puede aumentar la eficacia del primero y ayudar a alcanzar la visión de este último, especialmente para garantizar la salud y el bienestar en todas las edades. Su aplicación requiere una comprensión compartida entre individuos y sociedades sobre cómo la salud depende de múltiples factores presentes a lo largo de la vida y entre generaciones. La mayoría de los estudios se han centrado en las enfermedades no contagiosas, en el envejecimiento de la población en los países con ingresos altos y en cuestiones epidemiológicas, teóricas y clínicas. El objetivo de este artículo es mostrar cómo el enfoque basado en la salud para toda la vida se puede extender a todos los grupos de edades, temas de salud y países, mediante la creación de una síntesis de las pruebas científicas existentes, la experiencia en diferentes países y los avances en estrategias y programas de salud. Se presenta un marco conceptual del enfoque junto con las implicaciones para la aplicación en los siguientes campos: (i) política e inversión; (ii) servicios y sistemas de salud; (iii) acción local, multisectorial y de varias partes interesadas; y (iv) medición, supervisión e investigación. Los ODS proporcionan un contexto único para aplicar un enfoque holístico y multisectorial a fin de alcanzar unos resultados transformadores para las personas, la prosperidad y el medio ambiente. Un enfoque para toda la vida puede intensificar estos esfuerzos, sobre todo por su énfasis en los derechos y la equidad.

Status of New Vaccine Introduction - Worldwide, September 2016.

Since the global Expanded Program on Immunization (EPI) was launched in 1974, vaccination against six diseases (tuberculosis, polio, diphtheria, tetanus, pertussis, and measles) has prevented millions of deaths and disabilities (1). Significant advances have been made in the development and introduction of vaccines, and licensed vaccines are now available to prevent 25 diseases (2,3). Historically, new vaccines only became available in low-income and middle-income countries decades after being introduced in high-income countries. However, with the support of global partners, including the World Health Organization (WHO) and the United Nations Children's Fund, which assist with vaccine prequalification and procurement, as well as Gavi, the Vaccine Alliance (Gavi) (4), which provides funding and shapes vaccine markets through forecasting and assurances of demand in low-income countries in exchange for lower vaccine prices, vaccines are now introduced more rapidly. Based on data compiled in the WHO Immunization Vaccines and Biologicals Database* (5), this report describes the current status of introduction of Haemophilus influenzae type b (Hib), hepatitis B, pneumococcal conjugate, rotavirus, human papillomavirus, and rubella vaccines, and the second dose of measles vaccine. As of September 2016, a total of 191 (99%) of 194 WHO member countries had introduced Hib vaccine, 190 (98%) had introduced hepatitis B vaccine, 132 (68%) had introduced pneumococcal conjugate vaccine (PCV), and 86 (44%) had introduced rotavirus vaccine into infant vaccination schedules. Human papillomavirus vaccine (HPV) had been introduced in 67 (35%) countries, primarily targeted for routine use in adolescent girls. A second dose of measles-containing vaccine (MCV2) had been introduced in 161 (83%) countries, and rubella vaccine had been introduced in 149 (77%). These efforts support the commitment outlined in the Global Vaccine Action Plan (GVAP), 2011-2020 (2), endorsed by the World Health Assembly in 2012, to extend the full benefits of immunization to all persons.

Corrigendum: Gender analysis of the World Health Organization's online learning programme on Immunization Agenda 2030.

[This corrects the article DOI: 10.3389/fgwh.2023.1230109.].

Effect of intermittent preventive treatment for malaria during infancy on serological responses to measles and other vaccines used in the Expanded Programme on Immunization: results from five randomised controlled trials.

BACKGROUND: Intermittent preventive treatment for malaria during infancy (IPTi) is the administration of a full therapeutic course of antimalarial drugs to infants living in settings where malaria is endemic, at the time of routine vaccination in the first year of life. We investigated whether IPTi with sulfadoxine-pyrimethamine or other antimalarial drug combinations adversely affected serological responses to vaccines used in the Expanded Programme on Immunization (EPI). METHODS: The study was done in a subset of children enrolled in five randomised controlled trials in Navrongo, Ghana; Kilimanjaro, Tanzania; Manhica, Mozambique; Kisumu, Kenya; and Bungoma, Kenya. All infants presenting for the second dose of the diphtheria-tetanus-pertussis vaccination (given at 8-10 weeks of age) were eligible, and analyses included all children who had received measles vaccination (at 9 months of age) and at least one dose of IPTi or placebo. Blood samples were collected before and after vaccination, and antibody titres were measured by plaque reduction neutralisation (measles, yellow fever), microneutralisation (polio serotypes 1 and 3), and ELISA (all other EPI antigens). Laboratory personnel were unaware of the randomisation groups. We compared the proportion of infants in the IPTi and placebo groups who did not attain protective antibody titres after vaccination, using a one-sided significance non-inferiority margin of 5% for measles (the primary endpoint) and 10% for other EPI antigens. FINDINGS: Between September, 2000, and May, 2008, 8416 children were enrolled in the five studies. Paired samples from 2368 children from sites where sulfadoxine-pyrimethamine was compared with placebo were analysed for measles antibodies. 464 children with detectable measles antibody in their sample before vaccination were excluded, leaving 1904 individuals (934 placebo and 970 sulfadoxine-pyrimethamine) in the study. IPTi with sulfadoxine-pyrimethamine did not have a clinically significant effect on immune responses to measles vaccine; 61 of 970 (6·3%) children who received IPTi did not develop a protective antibody response after measles vaccination compared with 60 of 934 (6·4%) who received placebo, a difference of -0·14% (95% CI -2·3 to 2·1). When other antimalarial drugs were used for IPTi the results were much the same. Among 2396 children from whom serological response data for other EPI antigens were available, we identified no evidence of an adverse effect of IPTi with sulfadoxine-pyrimethamine or other antimalarial drugs on the proportion achieving protective antibody concentrations. INTERPRETATION: IPTi with sulfadoxine-pyrimethamine does not affect serological responses to EPI vaccines. This analysis, therefore, supports the WHO recommendation for coadministration of IPTi with sulfadoxine-pyrimethamine to infants at the time of the second and third doses of DTP and measles vaccination, in areas of sub-Saharan Africa with moderate to high malaria transmission and where malaria parasites are sensitive to these drugs. It also suggests that treatment of clinical malaria at or around the time of vaccination does not compromise vaccine responsiveness. FUNDING: Bill & Melinda Gates Foundation.

Gender analysis of the World Health Organization online learning program on Immunization Agenda 2030.

Vaccine-preventable diseases pose a significant threat to children under five globally, creating disparities in immunization coverage. Despite its cost-effectiveness and life-saving potential, immunization faces challenges in achieving equitable coverage. Gender inequalities deeply influence access to healthcare, affecting immunization rates. This study examines the action plans submitted by participants of the World Health Organization's (WHO) IA2030 Scholar Level 1 certification course in 2021. A qualitative analysis was conducted on a subset of 111 action plans that scored above 75%, employing narrative thematic analysis to categorize and explore gender incorporation and identified barriers based on the IA2030 Gender Guide. Among the 111 analyzed action plans, gender considerations were present in almost all plans, underscoring the effectiveness of integrating gender perspectives in the course curriculum. The most frequently cited barriers included low education and health literacy, issues related to accessing quality immunization services, gendered dynamics in decision-making within households, and limited access to resources and mobility, predominantly impacting women. The findings confirm that gender inequalities significantly contribute to suboptimal immunization coverage. An intersectional approach, recognizing diverse social markers impacting immunization, is vital to address disparities effectively. Moreover, the need for gender-sensitive data and deeper understanding of intersectional dynamics was emphasized. The study highlights the importance of gender-transformative interventions, including community engagement and efforts targeting both men and women to enhance immunization coverage. While acknowledging limitations, such as potential biases in peer evaluations and the need for wider inclusivity in gender perspectives, this analysis underscores the significance of mainstreaming gender in immunization capacity-building programs. The integration of gender considerations not only raises awareness but also equips professionals to create more gender-responsive immunization programs. Continuous efforts to incorporate gender perspectives can lead to more effective, equitable, and gender-transformative immunization initiatives at various levels.

A review of health worker vaccination programs in low, middle and upper middle-income countries.

Objectives: Health workers (HW) are at risk of contracting vaccine preventable diseases when caring for patients and communities. This study aims to evaluate the existing literature on the routine vaccination of health workers against a variety of antigens in low and middle income countries, focusing on facilitators, barriers, and considerations in the implementation of immunization programs and campaigns. Study design: A PubMed Literature search. Methods: A PubMed search was conducted to find articles that addressed vaccination programs and policies for HW in low-income countries (LIC), lower middle-income countries (LMIC), and upper middle-income countries (UMIC). Original articles, meta-analyses, and reviews published in English between January 2000 and July 2022 were included in the search. Inductive content analysis was used to identify themes that illustrate facilitators, barriers, and considerations in the implementation of immunization programs and campaigns. Results: The search identified 4240 studies, 90 were used for analysis as they provided antigen specific details on immunization policies or programs. Hepatitis B was the most frequently discussed antigen, followed by Influenza, then Measles, Rubella and Mumps. With considerable variability by vaccine and country, in most cases the vaccination was not offered free to HW or included in a regular vaccination schedule. Utilizing existing immunization infrastructure such as the Expanded Programme on Immunization (EPI) and having effective management of vaccination programs were found to be key facilitators to vaccinate HW. Conclusions: The low vaccination coverage of health workers in LMIC is of concern; attention towards the key considerations, barriers and facilitators of immunization implementation is central to the advancement of health worker vaccination coverage in LMIC's. The COVID-19 pandemic necessitated the swift vaccination of HW. Many LIC countries lacking established HW immunization infrastructure are now administering COVID-19 vaccines. As we move beyond the pandemic's acute phase, there is a chance for those countries to enhance their immunization initiatives and policies for HW concerning other antigens, even if it is not a standard practice currently.

The Association between Childhood Immunization and Gender Inequality: A Multi-Country Ecological Analysis of Zero-Dose DTP Prevalence and DTP3 Immunization Coverage.

This study explores the association between childhood immunization and gender inequality at the national level. Data for the study include annual country-level estimates of immunization among children aged 12-23 months, indicators of gender inequality, and associated factors for up to 165 countries from 2010-2019. The study examined the association between gender inequality, as measured by the gender development index and the gender inequality index, and two key outcomes: prevalence of children who received no doses of the DTP vaccine (zero-dose children) and children who received the third dose of the DTP vaccine (DTP3 coverage). Unadjusted and adjusted fractional logit regression models were used to identify the association between immunization and gender inequality. Gender inequality, as measured by the Gender Development Index, was positively and significantly associated with the proportion of zero-dose children (high inequality AOR = 1.61, 95% CI: 1.13-2.30). Consistently, full DTP3 immunization was negatively and significantly associated with gender inequality (high inequality AOR = 0.63, 95% CI: 0.46-0.86). These associations were robust to the use of an alternative gender inequality measure (the Gender Inequality Index) and were consistent across a range of model specifications controlling for demographic, economic, education, and health-related factors. Gender inequality at the national level is predictive of childhood immunization coverage, highlighting that addressing gender barriers is imperative to achieve universal coverage in immunization and to ensure that no child is left behind in routine vaccination.

Subnational Gender Inequality and Childhood Immunization: An Ecological Analysis of the Subnational Gender Development Index and DTP Coverage Outcomes across 57 Countries.

The role of gender inequality in childhood immunization is an emerging area of focus for global efforts to improve immunization coverage and equity. Recent studies have examined the relationship between gender inequality and childhood immunization at national as well as individual levels; we hypothesize that the demonstrated relationship between greater gender equality and higher immunization coverage will also be evident when examining subnational-level data. We thus conducted an ecological analysis examining the association between the Subnational Gender Development Index (SGDI) and two measures of immunization-zero-dose diphtheria-tetanus-pertussis (DTP) prevalence and 3-dose DTP coverage. Using data from 2010-2019 across 702 subnational regions within 57 countries, we assessed these relationships using fractional logistic regression models, as well as a series of analyses to account for the nested geographies of subnational regions within countries. Subnational regions were dichotomized to higher gender inequality (top quintile of SGDI) and lower gender inequality (lower four quintiles of SGDI). In adjusted models, we find that subnational regions with higher gender inequality (favoring men) are expected to have 5.8 percentage points greater zero-dose prevalence than regions with lower inequality [16.4% (95% confidence interval (CI) 14.5-18.4%) in higher-inequality regions versus 10.6% (95% CI 9.5-11.7%) in lower-inequality regions], and 8.2 percentage points lower DTP3 immunization coverage [71.0% (95% CI 68.3-73.7%) in higher-inequality regions versus 79.2% (95% CI 77.7-80.7%) in lower-inequality regions]. In models accounting for country-level clustering of gender inequality, the magnitude and strength of associations are reduced somewhat, but remain statistically significant in the hypothesized direction. In conjunction with published work demonstrating meaningful associations between greater gender equality and better childhood immunization outcomes in individual- and country-level analyses, these findings lend further strength to calls for efforts towards greater gender equality to improve childhood immunization and child health outcomes broadly.

A Systematic Review of the Sex and Gender Reporting in COVID-19 Clinical Trials.

Sex and gender have implications for COVID-19 vaccine efficacy and adverse effects from the vaccine. As vaccination is one of the key responses to the COVID-19 pandemic, it is vital that sex and gender differences be acknowledged, measured, and analysed in clinical research. Here, we systematically review published COVID-19 vaccine trials, both interventional and observational, to assess the quality of reporting of sex and gender. Of the 75 clinical trials on COVID-19 vaccines included in this review, only 24% presented their main outcome data disaggregated by sex, and only 13% included any discussion of the implications of their study for women and men. Considering the sex differences in adverse events after vaccination, and the gendered aspects of vaccine hesitancy, these oversights in clinical research on vaccines have implications for recovery from the COVID-19 pandemic and for wider public health.

Feasibility assessment of measles and rubella eradication.

This report addresses the epidemiological aspects and feasibility of measles and rubella eradication and the potential resource requirements in response to the request of the Director-General at the Seventieth World Health Assembly held on May 31, 2017. A guiding principle is that the path toward measles and rubella eradication should serve to strengthen primary health care, promote universal health coverage, and be a pathfinder for new vision and strategy for immunization over the next decade as laid out in the Immunization Agenda 2030. Specifically, this report: 1) highlights the importance of measles and rubella as global health priorities; 2) reviews the current global measles and rubella situation; 3) summarizes prior assessments of the feasibility of measles and rubella eradication; 4) assesses the progress and challenges in achieving regional measles and rubella elimination; 5) assesses additional considerations for measles and rubella eradication, including the results of modelling and economic analyses; 6) assesses the implications of establishing a measles and rubella eradication goal and the process for setting an eradication target date; 7) proposes a framework for determining preconditions for setting a target date for measles and rubella eradication and how these preconditions should be understood and used; and 8) concludes with recommendations endorsed by SAGE.

Use of tetanus-diphtheria (Td) vaccine in children 4-7 years of age: World Health Organization consultation of experts.

For lifetime protection against diphtheria and tetanus, the World Health Organization (WHO) recommends six doses of diphtheria and tetanus containing vaccines. Td (reduced diphtheria toxoid, ≥2-5 IU) vaccines are currently licensed for ages 7 years and older, but use of Td vaccine for ages 4 years and older would have advantages for immunization programs in many low- and middle-income countries. For this reason, WHO convened an expert consultation to review the currently available evidence for the use of Td vaccine from 4 to 7 years of age which concluded: (1) no relevant biological difference in immune response in the relevant age group compared with children over 7 years of age; (2) adequate seroprotection in several studies with Td vaccine in the 4-7 age group and many studies using combination vaccines; (3) durable and protective response of at least 9-11 years duration in several longitudinal and modelling studies, (4) less reactogenicity compared with use of full-dose diphtheria vaccine, potentially improving the vaccination experience; and (5) adequate control of diphtheria in several countries using Td-containing combination vaccines in 4-7 year old children. On this basis, the experts concluded that from a programmatic perspective, Td vaccine given in ages 4-7 years, as a second booster dose in a six-dose series, would provide adequate protection against diphtheria and tetanus and recommended steps to include this change in age extension listed in the package insert.

Immunogenicity, effectiveness, and safety of measles vaccination in infants younger than 9 months: a systematic review and meta-analysis.

BACKGROUND: Measles is an important cause of death in children, despite the availability of safe and cost-saving measles-containing vaccines (MCVs). The first MCV dose (MCV1) is recommended at 9 months of age in countries with ongoing measles transmission, and at 12 months in countries with low risk of measles. To assess whether bringing forward the age of MCV1 is beneficial, we did a systematic review and meta-analysis of the benefits and risks of MCV1 in infants younger than 9 months. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, EMBASE, Scopus, Proquest, Global Health, the WHO library database, and the WHO Institutional Repository for Information Sharing database, and consulted experts. We included randomised and quasi-randomised controlled trials, outbreak investigations, and cohort and case-control studies without restriction on publication dates, in which MCV1 was administered to infants younger than 9 months. We did the literature search on June 2, 2015, and updated it on Jan 14, 2019. We assessed: proportion of infants seroconverted, geometric mean antibody titre, avidity, cellular immunity, duration of immunity, vaccine efficacy, vaccine effectiveness, and safety. We used random-effects models to derive pooled estimates of the endpoints, where appropriate. We assessed methodological quality using the Grading of Recommendations, Assessment, Development, and Evaluation guidelines. FINDINGS: Our search identified 1156 studies, of which 1071 were screened for eligibility. 351 were eligible for full-text screening, and data from 56 studies that met all inclusion criteria were used for analysis. The proportion of infants who seroconverted increased from 50% (95% CI 29-71) for those vaccinated with MCV1 at 4 months of age to 85% (69-97) for those were vaccinated at 8 months. The pooled geometric mean titre ratio for infants aged 4-8 months vaccinated with MCV1 compared with infants vaccinated with MCV1 at age 9 months or older was 0·46 (95% CI 0·33-0·66; I2=99·9%, p<0·0001). Only one study reported on avidity and suggested that there was lower avidity and a shorter duration of immunity following MCV1 administration at 6 months of age than at 9 months of age (p=0·0016) or 12 months of age (p<0·001). No effect of age at MCV1 administration on cellular immunity was found. One study reported that vaccine efficacy against laboratory-confirmed measles virus infection was 94% (95% CI 74-98) in infants vaccinated with MCV1 at 4·5 months of age. The pooled vaccine effectiveness of MCV1 in infants younger than 9 months against measles was 58% (95% CI 9-80; I2=84·9%, p<0·0001). The pooled vaccine effectiveness estimate from within-study comparisons of infants younger than 9 months vaccinated with MCV1 were 51% (95% CI -44 to 83; I2=92·3%, p<0·0001), and for those aged 9 months and older at vaccination it was 83% (76-88; I2=93·8%, p<0·0001). No differences in the risk of adverse events after MCV1 administration were found between infants younger than 9 months and those aged 9 months of older. Overall, the quality of evidence ranged from moderate to very low. INTERPRETATION: MCV1 administered to infants younger than 9 months induces a good immune response, whereby the proportion of infants seroconverted increases with increased age at vaccination. A large proportion of infants receiving MCV1 before 9 months of age are protected and the vaccine is safe, although higher antibody titres and vaccine effectiveness are found when MCV1 is administered at older ages. Recommending MCV1 administration to infants younger than 9 months for those at high risk of measles is an important step towards reducing measles-related mortality and morbidity. FUNDING: WHO.

Effect of measles vaccination in infants younger than 9 months on the immune response to subsequent measles vaccine doses: a systematic review and meta-analysis.

BACKGROUND: Vaccinating infants with a first dose of measles-containing vaccine (MCV1) before 9 months of age in high-risk settings has the potential to reduce measles-related morbidity and mortality. However, there is concern that early vaccination might blunt the immune response to subsequent measles vaccine doses. We systematically reviewed the available evidence on the effect of MCV1 administration to infants younger than 9 months on their immune responses to subsequent MCV doses. METHODS: For this systematic review and meta-analysis, we searched for randomised and quasi-randomised controlled trials, outbreak investigations, and cohort and case-control studies without restriction on publication dates, in which MCV1 was administered to infants younger than 9 months. We did the literature search on June 2, 2015, and updated it on Jan 14, 2019. We included studies reporting data on strength or duration of humoral and cellular immune responses, and on vaccine efficacy or vaccine effectiveness after two-dose or three-dose MCV schedules. Our outcome measures were proportion of seropositive infants, geometric mean titre, vaccine efficacy, vaccine effectiveness, antibody avidity index, and T-cell stimulation index. We used random-effects meta-analysis to derive pooled estimates of the outcomes, where appropriate. We assessed the methodological quality of included studies using Grading of Recommendation Assessment, Development and Evaluation (GRADE) guidelines. FINDINGS: Our search retrieved 1156 records and 85 were excluded due to duplication. 1071 records were screened for eligibility, of which 351 were eligible for full-text screening and 21 were eligible for inclusion in the review. From 13 studies, the pooled proportion of infants seropositive after two MCV doses, with MCV1 administered before 9 months of age, was 98% (95% CI 96-99; I2=79·8%, p<0·0001), which was not significantly different from seropositivity after a two-dose MCV schedule starting later (p=0·087). Only one of four studies found geometric mean titres after MCV2 administration to be significantly lower when MCV1 was administered before 9 months of age than at 9 months of age or later. There was insufficient evidence to determine an effect of age at MCV1 administration on antibody avidity. The pooled vaccine effectiveness estimate derived from two studies of a two-dose MCV schedule with MCV1 vaccination before 9 months of age was 95% (95% CI 89-100; I2=12·6%, p=0·29). Seven studies reporting on measles virus-specific cellular immune responses found that T-cell responses and T-cell memory were sustained, irrespective of the age of MCV1 administration. Overall, the quality of evidence was moderate to very low. INTERPRETATION: Our findings suggest that administering MCV1 to infants younger than 9 months followed by additional MCV doses results in high seropositivity, vaccine effectiveness, and T-cell responses, which are independent of the age at MCV1, supporting the vaccination of very young infants in high-risk settings. However, we also found some evidence that MCV1 administered to infants younger than 9 months resulted in lower antibody titres after one or two subsequent doses of MCV than when measles vaccination is started at age 9 months or older. The clinical and public-health relevance of this immunity blunting effect are uncertain. FUNDING: WHO.

Ending preventable child deaths from pneumonia and diarrhoea by 2025. Development of the integrated Global Action Plan for the Prevention and Control of Pneumonia and Diarrhoea.

Despite the existence of low-cost and effective interventions for childhood pneumonia and diarrhoea, these conditions remain two of the leading killers of young children. Based on feedback from health professionals in countries with high child mortality, in 2009, WHO and Unicef began conceptualising an integrated approach for pneumonia and diarrhoea control. As part of this initiative, WHO and Unicef, with support from other partners, conducted a series of five workshops to facilitate the inclusion of coordinated actions for pneumonia and diarrhoea into the national health plans of 36 countries with high child mortality. This paper presents the findings from workshop and post-workshop follow-up activities and discusses the contribution of these findings to the development of the integrated Global Action Plan for the Prevention and Control of Pneumonia and Diarrhoea, which outlines the necessary actions for elimination of preventable child deaths from pneumonia and diarrhoea by 2025. Though this goal is ambitious, it is attainable through concerted efforts. By applying the lessons learned thus far and continuing to build upon them, and by leveraging existing political will and momentum for child survival, national governments and their supporting partners can ensure that preventable child deaths from pneumonia and diarrhoea are eventually eliminated.

Safety and impact of vitamin A supplementation delivered with oral polio vaccine as part of the immunization campaign in Orissa, India.

A study was carried out in Orissa, India, to evaluate the impact on vitamin A status of vitamin A supplementation integrated with an immunization campaign. Data were collected from a representative sample of 1,811 children, aged 12 to 48 months, at baseline and then at 4 and 16 weeks following implementation of vitamin A supplementation. The primary outcome indicator was serum retinol. The coverage of vitamin A supplementation was 97%. There was a significant decline in the prevalence of Bitot's spots from 2.9% to 1.9% at 4 weeks, but the prevalence increased to 3.6% by 16 weeks. Serum retinol concentrations increased between baseline and 4 weeks (from 0.62 +/- 0.32 to 0.73 +/- 0.23 mumol/L, p < .001) but then decreased to 0.50 +/- 0.19 mumol/l at 16 weeks, which was significantly lower than at baseline (p < .001). The greatest increase in serum retinol from baseline to 4-week follow-up was among children with lowest baseline serum retinol and children with Bitot's spots at baseline. This study demonstrates the short-term benefits of vitamin A supplementation to be significant, especially for those whose status is most compromised. At the same time, the benefit of vitamin A supplementation in this population was transient. The impact of the vitamin A could not be sustained for the full 16 weeks in the study population. This finding calls for exploration of other means to improve vitamin A status, perhaps by adjusting the vitamin A supplementation schedule with more aggressive measures to improve intake of foods rich in bioavailable vitamin A, such as small amounts of animal foods or fortified foods. The study demonstrates the feasibility of integrating vitamin A supplementation with immunization campaigns.

Impact of targeted programs on health systems: a case study of the polio eradication initiative.

The results of 2 large field studies on the impact of the polio eradication initiative on health systems and 3 supplementary reports were presented at a December 1999 meeting convened by the World Health Organization. All of these studies concluded that positive synergies exist between polio eradication and health systems but that these synergies have not been vigorously exploited. The eradication of polio has probably improved health systems worldwide by broadening distribution of vitamin A supplements, improving cooperation among enterovirus laboratories, and facilitating linkages between health workers and their communities. The results of these studies also show that eliminating polio did not cause a diminution of funding for immunization against other illnesses. Relatively little is known about the opportunity costs of polio eradication. Improved planning in disease eradication initiatives can minimize disruptions in the delivery of other services. Future initiatives should include indicators and baseline data for monitoring effects on health systems development.

Ensuring injection safety during measles immunization campaigns: more than auto-disable syringes and safety boxes.

Measles immunization campaigns are effective elements of a comprehensive strategy for preventing measles cases and deaths. However, if immunizations are not properly administered or if immunization waste products are not safely managed, there is the potential to transmit bloodborne pathogens (e.g., human immunodeficiency virus and hepatitis B and hepatitis C). A safe injection can be defined as one that results in no harm to the recipient, the vaccinator, and the surrounding community. Proper equipment, such as the exclusive use of auto-disable syringes and safety boxes, is necessary, but these alone are not sufficient to ensure injection safety in immunization campaigns. Equally important are careful planning and managerial activities that include policy and strategy development, financing, budgeting, logistics, training, supervision, and monitoring. The key elements that must be in place to ensure injection safety in measles immunization campaigns are outlined.