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Strategic Priority 4 (SP4) of the Immunization Agenda 2030 aims to ensure that all people benefit from recommended immunizations throughout the life-course, integrated with essential health services. Therefore, it is necessary for immunization programs to have coordination and collaboration across all health programs. Although there has been progress, immunization platforms in the second year of life and beyond need continued strengthening, including booster doses and catch-up vaccination, for all ages, and recommended vaccines for older age groups. We note gaps in current vaccination programs policies and achieved coverage, in the second year of life and beyond. In 2021, the second dose of measles-containing vaccine (MCV2), given in the second year of life, achieved 71% global coverage vs 81% for MCV1. For adolescents, 60% of all countries have adopted human papillomavirus vaccines in their vaccination schedule with a global coverage rate of only 12 percent in 2021. Approximately 65% of the countries recommend influenza vaccines for older adults, high-risk adults and pregnant women, and only 25% recommended pneumococcal vaccines for older adults. To achieve an integrated life course approach to vaccination, we reviewed the evidence, gaps, and strategies in four focus areas: generating evidence for disease burden and potential vaccine impact in older age groups; building awareness and shifting policy beyond early childhood; building integrated delivery approaches throughout the life course; and identifying missed opportunities for vaccination, implementing catch-up strategies, and monitoring vaccination throughout the life course. We identified needs, such as tailoring strategies to the local context, conducting research and advocacy to mobilize resources and build political will. Mustering sufficient financial support and demand for an integrated life course approach to vaccination, particularly in times of COVID-19, is both a challenge and an opportunity., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 World Health Organization. Published by Elsevier Ltd.. All rights reserved.)

Objectives: To examine the characteristics of existing maternal tetanus immunization programmes for pregnant women in low- and middle-income countries (LMICs) and to identify and understand the challenges, barriers and facilitators associated with maternal vaccine service delivery that may impact the introduction and implementation of new maternal vaccines in the future., Design: A mixed methods, cross sectional study with four data collection phases including a desk review, online survey, telephone and face-to-face interviews and in country visits., Setting: LMICs., Results: The majority of countries (84/95; 88%) had a maternal tetanus immunization policy. Countries with high protection at birth (PAB) were more likely to report tetanus toxoid-containing vaccine (TTCV) coverage targets > 90%. Less than half the countries included in this study had a TTCV coverage target of > 90%. Procurement and distribution of TTCV was nearly always the responsibility of the Expanded Programme on Immunization (EPI), however planning and management of maternal immunization was often shared between EPI and Maternal, Newborn and Child Health (MNCH) programmes. Receipt of TTCV at the same time as the antenatal care visit correlated with high PAB. Most countries (81/95; 85%) had an immunization safety surveillance system in place although only 11% could differentiate an adverse event following immunization (AEFI) in pregnant and non-pregnant women., Conclusions: Recommendations arising from the MIACSA project to strengthen existing services currently delivering maternal tetanus immunization in LMICs include establishing and maintaining vaccination targets, clearly defining responsibilities and fostering collaborations between EPI and MNCH, investing in strengthening the health workforce, improving the design and use of existing record keeping for immunization, adjusting current AEFI reporting to differentiate pregnant women and endeavoring to integrate the provision of TTCV within ANC services where appropriate., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. The authors alone are responsible for the views expressed in this article and they do not necessarily represent the views, decisions or policies of the institutions with which they are affiliated., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.)

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; I 2 =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; I 2 =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., (Copyright © 2019 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY-NC-ND 4.0 license. Published by Elsevier Ltd.. All rights reserved.)

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; I 2 =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; I 2 =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; I 2 =92·3%, p<0·0001), and for those aged 9 months and older at vaccination it was 83% (76-88; I 2 =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., (Copyright © 2019 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY-NC-ND 4.0 license. Published by Elsevier Ltd.. All rights reserved.)

Background: In 2012, cryptosporidiosis cases increased in the Netherlands, but no single source was identified. In April 2013, we began a 3-year population-based case-control study coupled with genotyping to identify risk factors for sporadic cryptosporidiosis., Methods: Cryptosporidium cases were laboratory confirmed (by microscopy or polymerase chain reaction), and the species (ie, C. hominis or C. parvum) was determined. We analyzed data by study year, combined and by species. We performed single-variable analysis, and variables with a P value of ≤ .10 were included in a multivariable logistic regression model adjusting for age, sex, and season., Results: The study included 609 cases and 1548 frequency-matched controls. C. parvum was the predominant species in the first 2 study years, shifting to C. hominis in the third year. Household person-to-person transmission and eating barbequed food were strongly associated with being a case. Eating tomatoes was negatively associated. When the analysis was stratified by study year, person-to-person transmission was an independent risk factor. Analysis by species identified different risk factors for cases infected with C. parvum and C. hominis., Conclusion: This was the first case-control study examining risk factors for sporadic cryptosporidiosis in the Netherlands. Providing information about Cryptosporidium exposure during outdoor activities and improvements in hygiene within households could prevent future sporadic infections., (© The Author(s) 2018. Published by Oxford University Press for the Infectious Diseases Society of America.)

Background: During the 2014-16 Ebola virus disease (EVD) outbreak, the Magburaka Ebola Management Centre (EMC) operated by Médecins Sans Frontières (MSF) in Tonkolili District, Sierra Leone, identified that available district maps lacked up-to-date village information to facilitate timely implementation of EVD control strategies. In January 2015, we undertook a survey in chiefdoms within the MSF EMC catchment area to collect mapping and village data. We explore the feasibility and cost to mobilise a local community for this survey, describe validation against existing mapping sources and use of the data to prioritise areas for interventions, and lessons learned., Methods: We recruited local people with self-owned Android smartphones installed with open-source survey software (OpenDataKit (ODK)) and open-source navigation software (OpenStreetMap Automated Navigation Directions (OsmAnd)). Surveyors were paired with local motorbike drivers to travel to eligible villages. The collected mapping data were validated by checking for duplication and comparing the village names against a pre-existing village name and location list using a geographic distance and text string-matching algorithm., Results: The survey teams gained sufficient familiarity with the ODK and OsmAnd software within 1-2 hours. Nine chiefdoms in Tonkolili District and three in Bombali District were surveyed within two weeks. Following de-duplication, the surveyors collected data from 891 villages with an estimated 127,021 households. The overall survey cost was €3,395; €3.80 per village surveyed. The MSF GIS team (MSF-OCG) created improved maps for the MSF Magburaka EMC team which were used to support surveillance, investigation of suspect EVD cases, hygiene-kit distribution and EVD survivor support. We shared the mapping data with OpenStreetMap, the local Ministry of Health and Sanitation and Sierra Leone District and National Ebola Response Centres., Conclusions: Involving local community and using accessible technology allowed rapid implementation, at moderate cost, of a survey to collect geographic and essential village information, and creation of updated maps. These methods could be used for future emergencies to facilitate response.

Background: During a large measles outbreak in the Netherlands in 2013-2014, infants aged 6-14months living in municipalities with low (<90%) measles-mumps-rubella (MMR) coverage were individually invited for an early MMR using the national electronic immunization register, Præventis. We estimated uptake of early MMR prior to and during the 2013-2014 outbreak and assessed determinants for early MMR vaccination., Methods: We obtained vaccination records from Præventis, and defined early MMR as vaccination before 415days (13months) of age. A multi-level multivariable logistic regression model, restricted to infants with three diphtheria-pertussis-tetanus-polio (DPTP) vaccinations was used to examine the association between early MMR uptake and sex, parents' country of birth, socioeconomic status (SES; at postcode level) and voting proportions for the Reformed Political Party (SGP; at municipal level), used as a proxy for religious objections towards vaccination., Results: In the 29 municipalities with low MMR coverage, uptake of early MMR was 0.5-2.2% prior to the outbreak. Between July 2013 and March 2014, 5,800 (57%) invited infants received an early MMR. Among infants with three DPTP, 70% received an early MMR. Only 1% of infants without prior DPTP received an early MMR. Lower early MMR uptake was associated with a higher SGP voter-ship (OR 0.89 per 5% increase, 95%CI 0.83-0.96), parents' with unknown country of birth (OR 0.66 95%CI 0.47-0.93) and compared with very high SES, high SES had significantly lower early MMR uptake (OR 0.66 95%CI 0.50-0.87)., Discussion: This is the first study describing use of Præventis during an outbreak and to assess determinants of early MMR uptake. More than half of invited infants obtained an early MMR. SES, parents' with unknown country of birth and religious objections towards vaccination were found to be associated with lower early MMR uptake. In future outbreaks, these determinants could be used to tailor intervention strategies., (Copyright © 2017. Published by Elsevier Ltd.)

Background:  We investigated a measles outbreak among healthcare workers (HCWs) by assessing laboratory characteristics, measles vaccine effectiveness, and serological correlates for protection., Methods:  Cases were laboratory-confirmed measles in HCWs from hospital X during weeks 12-20 of 2014. We assessed cases' severity and infectiousness by using a questionnaire. We tested cases' sera for measles immunoglobulin M, immunoglobulin G, avidity, and plaque reduction neutralization (PRN). Throat swabs and oral fluid samples were tested by quantitative polymerase chain reaction. We calculated attack rates (ARs) by vaccination status and estimated measles vaccine effectiveness as 1 - [AR vaccinated /AR unvaccinated ]., Results:  Eight HCWs were notified as measles cases; 6 were vaccinated with measles vaccine twice, 1 was vaccinated once, and 1 was unvaccinated. All 6 twice-vaccinated cases had high avidity and PRN titers. None reported severe measles or onward transmission. Two of 4 investigated twice-vaccinated cases had pre-illness PRN titers of >120 mIU/mL. Among 106 potentially exposed HCWs, the estimated effectiveness of 2 doses of measles vaccine was 52% (95% confidence interval [CI], -207%-93%)., Conclusions:  Measles occurred in 6 twice-vaccinated HCWs, despite 2 having adequate pre-exposure neutralizing antibodies. None of the twice-vaccinated cases had severe measles, and none had onward transmission, consistent with laboratory findings suggesting a secondary immune response. Improving 2-dose MMR coverage among HCWs would have likely reduced the size of this outbreak., (© The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.)