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Muhoza P, Shah MP, Amponsa-Achiano K, Gao H, Quaye P, Opare W, Okae C, Aboyinga PN, Opare JKL, Ehlman DC, Wardle MT, Wallace AS. Timeliness of Childhood Vaccinations Following Strengthening of the Second Year of Life (2YL) Immunization Platform and Introduction of Catch-Up Vaccination Policy in Ghana. Vaccines (Basel) 2024; 12:716. [PMID: 39066354 PMCID: PMC11281534 DOI: 10.3390/vaccines12070716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2024] [Revised: 06/20/2024] [Accepted: 06/23/2024] [Indexed: 07/28/2024] Open
Abstract
Strengthening routine immunization systems to successfully deliver childhood vaccines during the second year of life (2YL) is critical for vaccine-preventable disease control. In Ghana, the 18-month visit provides opportunities to deliver the second dose of the measles-rubella vaccine (MR2) and for healthcare workers to assess for and provide children with any missed vaccine doses. In 2016, the Ghana Health Service (GHS) revised its national immunization policies to include guidelines for catch-up vaccinations. This study assessed the change in the timely receipt of vaccinations per Ghana's Expanded Program on Immunizations (EPI) schedule, an important indicator of service quality, following the introduction of the catch-up policy and implementation of a multifaceted intervention package. Vaccination coverage was assessed from household surveys conducted in the Greater Accra, Northern, and Volta regions for 392 and 931 children aged 24-35 months with documented immunization history in 2016 and 2020, respectively. Age at receipt of childhood vaccines was compared to the recommended age, as per the EPI schedule. Cumulative days under-vaccinated during the first 24 months of life for each recommended dose were assessed. Multivariable Cox regression was used to assess the associations between child and caregiver characteristics and time to MR2 vaccination. From 2016 to 2020, the proportion of children receiving all recommended doses on schedule generally improved, the duration of under-vaccination was shortened for most doses, and higher coverage rates were achieved at earlier ages for the MR series. More timely infant doses and caregiver awareness of the 2YL visit were positively associated with MR2 vaccination. Fostering a well-supported cadre of vaccinators, building community demand for 2YL vaccination, sustaining service utilization through strengthened defaulter tracking and caregiver-reminder systems, and creating a favorable policy environment that promotes vaccination over the life course are critical to improving the timeliness of childhood vaccinations.
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Affiliation(s)
- Pierre Muhoza
- Global Immunization Division, U.S. Centers for Disease Control and Prevention, Atlanta, GA 30329, USA
- Epidemic Intelligence Service, U.S. Centers for Disease Control and Prevention, Atlanta, GA 30329, USA
| | - Monica P. Shah
- Global Immunization Division, U.S. Centers for Disease Control and Prevention, Atlanta, GA 30329, USA
| | - Kwame Amponsa-Achiano
- Expanded Programme on Immunisation, Disease Control and Prevention Department, Public Health Division, Ghana Health Service, Accra P.O. Box M 44, Ghana
| | - Hongjiang Gao
- Global Immunization Division, U.S. Centers for Disease Control and Prevention, Atlanta, GA 30329, USA
| | - Pamela Quaye
- Expanded Programme on Immunisation, Disease Control and Prevention Department, Public Health Division, Ghana Health Service, Accra P.O. Box M 44, Ghana
| | - William Opare
- Expanded Programme on Immunisation, Disease Control and Prevention Department, Public Health Division, Ghana Health Service, Accra P.O. Box M 44, Ghana
| | - Charlotte Okae
- Expanded Programme on Immunisation, Disease Control and Prevention Department, Public Health Division, Ghana Health Service, Accra P.O. Box M 44, Ghana
| | - Philip-Neri Aboyinga
- Expanded Programme on Immunisation, Disease Control and Prevention Department, Public Health Division, Ghana Health Service, Accra P.O. Box M 44, Ghana
| | - Joseph Kwadwo Larbi Opare
- Neglected Tropical Diseases Control Programme, Disease Control and Prevention Department, Public Health Division, Ghana Health Service, Accra P.O. Box M 44, Ghana
| | - Daniel C. Ehlman
- Global Immunization Division, U.S. Centers for Disease Control and Prevention, Atlanta, GA 30329, USA
| | - Melissa T. Wardle
- Global Immunization Division, U.S. Centers for Disease Control and Prevention, Atlanta, GA 30329, USA
| | - Aaron S. Wallace
- Global Immunization Division, U.S. Centers for Disease Control and Prevention, Atlanta, GA 30329, USA
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Wariri O, Okomo U, Kwarshak YK, Utazi CE, Murray K, Grundy C, Kampmann B. Timeliness of routine childhood vaccination in 103 low-and middle-income countries, 1978-2021: A scoping review to map measurement and methodological gaps. PLOS GLOBAL PUBLIC HEALTH 2022; 2:e0000325. [PMID: 36962319 PMCID: PMC10021799 DOI: 10.1371/journal.pgph.0000325] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 06/14/2022] [Indexed: 11/19/2022]
Abstract
Empiric studies exploring the timeliness of routine vaccination in low-and middle-income countries (LMICs) have gained momentum in the last decade. Nevertheless, there is emerging evidence suggesting that these studies have key measurement and methodological gaps that limit their comparability and utility. Hence, there is a need to identify, and document these gaps which could inform the design, conduct, and reporting of future research on the timeliness of vaccination. We synthesised the literature to determine the methodological and measurement gaps in the assessment of vaccination timeliness in LMICs. We searched five electronic databases for peer-reviewed articles in English and French that evaluated vaccination timeliness in LMICs, and were published between 01 January 1978, and 01 July 2021. Two reviewers independently screened titles and abstracts and reviewed full texts of relevant articles, following the guidance framework for scoping reviews by the Joanna Briggs Institute. From the 4263 titles identified, we included 224 articles from 103 countries. China (40), India (27), and Kenya (23) had the highest number of publications respectively. Of the three domains of timeliness, the most studied domain was 'delayed vaccination' [99.5% (223/224)], followed by 'early vaccination' [21.9% (49/224)], and 'untimely interval vaccination' [9% (20/224)]. Definitions for early (seven different definitions), untimely interval (four different definitions), and delayed vaccination (19 different definitions) varied across the studies. Most studies [72.3% (166/224)] operationalised vaccination timeliness as a categorical variable, compared to only 9.8% (22/224) of studies that operationalised timeliness as continuous variables. A large proportion of studies [47.8% (107/224)] excluded the data of children with no written vaccination records irrespective of caregivers' recall of their vaccination status. Our findings show that studies on vaccination timeliness in LMICs has measurement and methodological gaps. We recommend the development and implement of guidelines for measuring and reporting vaccination timeliness to bridge these gaps.
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Affiliation(s)
- Oghenebrume Wariri
- Vaccines and Immunity Theme, MRC Unit The Gambia at London School of Hygiene and Tropical Medicine, Fajara, The Gambia
- Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, United Kingdom
- Vaccine Centre, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Uduak Okomo
- Vaccines and Immunity Theme, MRC Unit The Gambia at London School of Hygiene and Tropical Medicine, Fajara, The Gambia
| | | | - Chigozie Edson Utazi
- WorldPop, School of geography and Environmental Science, University of Southampton, Southampton, United Kingdom
- Southampton Statistical Sciences Research Institute, University of Southampton, Southampton, United Kingdom
| | - Kris Murray
- MRC Unit The Gambia at The London School of Hygiene and Tropical Medicine, Fajara, The Gambia
- MRC Centre for Global Infectious Disease Analysis, Imperial College School of Public Health, Imperial College London, London, United Kingdom
| | - Chris Grundy
- Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Beate Kampmann
- Vaccines and Immunity Theme, MRC Unit The Gambia at London School of Hygiene and Tropical Medicine, Fajara, The Gambia
- Vaccine Centre, London School of Hygiene and Tropical Medicine, London, United Kingdom
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Huang Y, Danovaro-Holliday MC. Characterization of immunization secondary analyses using demographic and health surveys (DHS) and multiple indicator cluster surveys (MICS), 2006-2018. BMC Public Health 2021; 21:351. [PMID: 33581740 PMCID: PMC7880859 DOI: 10.1186/s12889-021-10364-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2020] [Accepted: 01/31/2021] [Indexed: 11/02/2022] Open
Abstract
BACKGROUND Infant immunization coverage worldwide has plateaued at about 85%. Using existing survey data to conduct analyses beyond estimating coverage may help immunization programmes better tailor strategies to reach un- and under-immunized children. The Demographic and Health Survey (DHS) and the Multiple Indicators Cluster Survey (MICS), routinely conducted in low and middle-income countries (LMICs), collect immunization data, yet vaccination coverage is often the only indicator reported and used. We conducted a review of published immunization-related analyses to characterize and quantify immunization secondary analyses done using DHS and MICS databases. METHODS We conducted a systematic search of the literature, of immunization-related secondary analyses from DHS or MICS published between 2006 and August 2018. We searched 15 electronic databases without language restrictions. For the articles included, relevant information was extracted and analyzed to summarize the characteristics of immunization-related secondary analyses. Results are presented following the PRISMA guidelines. RESULTS Among 1411 papers identified, 115 met our eligibility criteria; additionally, one article was supplemented by the Pan American Health Organization. The majority were published since 2012 (77.6%), and most (68.9%) had a first or corresponding author affiliated with institutions in high-income countries (as opposed to LMICs where these surveys are conducted). The median delay between survey implementation and publication of the secondary analysis was 5.4 years, with papers with authors affiliated to institutions in LMIC having a longer median publication delay (p < 0.001). Over 80% of the published analyses looked at factors associated with a specific vaccine or with full immunization. Quality proxies, such as reporting percent of immunization data from cards vs recall; occurrence and handling of missing data; whether survey analyses were weighted; and listing of potential biases or limitations of the original survey or analyses, were infrequently mentioned. CONCLUSION Our review suggests that more needs to be done to increase the increase the utilization of existing DHS and MICS datasets and improve the quality of the analyses to inform immunization programmes. This would include increasing the proportion of analyses done in LMICs, reducing the time lag between survey implementation and publication of additional analyses, and including more qualitative information about the survey in the publications to better interpret the results.
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Affiliation(s)
- Yue Huang
- Department of Immunization, Immunization, Analytics and Insights (IAI), Vaccines and Biologicals (IVB), World Health Organization (WHO), 1211, Geneva, Switzerland
- Present affiliation: State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Strait Collaborative Innovation Center of Biomedicine and Pharmaceutics, School of Public Health, Xiamen University, Xiamen, 361102, China
| | - M Carolina Danovaro-Holliday
- Department of Immunization, Immunization, Analytics and Insights (IAI), Vaccines and Biologicals (IVB), World Health Organization (WHO), 1211, Geneva, Switzerland.
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Janusz CB, Frye M, Mutua MK, Wagner AL, Banerjee M, Boulton ML. Vaccine Delay and Its Association With Undervaccination in Children in Sub-Saharan Africa. Am J Prev Med 2021; 60:S53-S64. [PMID: 33189500 PMCID: PMC10601532 DOI: 10.1016/j.amepre.2020.10.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 10/02/2020] [Accepted: 10/02/2020] [Indexed: 11/24/2022]
Abstract
INTRODUCTION Improving the timeliness and completion of vaccination is the key to reducing under-5 childhood mortality. This study examines the prevalence of delayed vaccination for doses administered at birth and age 6 weeks, 10 weeks, 14 weeks, and 9 months and its association with undervaccination among infants in Sub-Saharan Africa. METHODS Pooling data across 33 Sub-Saharan Africa countries, vaccination timing and series completion were assessed for children aged 12-35 months who were included in the immunization module of the Demographic and Health Surveys conducted between 2010 and 2019. Survey design-adjusted logistic regression modeled the likelihood of not fully completing the basic immunization schedule associated with dose-specific delays in vaccination. Data were obtained and analyzed in May 2020. RESULTS Among children with complete date records (n=70,006), the proportion of children vaccinated with delays by ≥1 month was high: 25.9% for Bacille Calmette-Guerin (at birth); 49.1% for the third dose of pentavalent combination vaccine (at 14 weeks); and 63.9% for the first dose of measles vaccines (at 9 months). Late vaccination was more common for children born to mothers with lower levels of educational attainment (p<0.001) and wealth (p<0.001). Controlling for place, time, and sociodemographics, vaccination delays at any dose were significantly associated with not completing the immunization schedule by 12 months (Bacille Calmette-Guerin: AOR=1.93, [95% CI=1.83, 2.02]; pentavalent 3: AOR=1.50 [95% CI=1.35, 1.64]; measles: AOR=3.76 [95% CI=3.37, 4.15]). CONCLUSIONS Timely initiation of vaccination could contribute to higher rates of immunization schedule completion, improving the reach and impact of vaccination programs on child health outcomes in Sub-Saharan Africa. SUPPLEMENT INFORMATION This article is part of a supplement entitled Global Vaccination Equity, which is sponsored by the Global Institute for Vaccine Equity at the University of Michigan School of Public Health.
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Affiliation(s)
- Cara Bess Janusz
- Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, Michigan; The Global Institute for Vaccine Equity, University of Michigan, Ann Arbor, Michigan.
| | - Margaret Frye
- Department of Sociology, College of Literature, Science, and the Arts, University of Michigan, Ann Arbor, Michigan
| | - Martin K Mutua
- African Population and Health Research Center, Nairobi, Kenya
| | - Abram L Wagner
- Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, Michigan; The Global Institute for Vaccine Equity, University of Michigan, Ann Arbor, Michigan
| | - Mousumi Banerjee
- Department of Biostatistics, School of Public Health, University of Michigan, Ann Arbor, Michigan; Center for Healthcare Outcomes & Policy, University of Michigan, Ann Arbor, Michigan
| | - Matthew L Boulton
- Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, Michigan; The Global Institute for Vaccine Equity, University of Michigan, Ann Arbor, Michigan; Infectious Disease Division, Department of Internal Medicine, Michigan Medicine, Ann Arbor, Michigan
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Boulton ML, Carlson BF, Wagner AL, Porth JM, Gebremeskel B, Abeje Y. Vaccination timeliness among newborns and infants in Ethiopia. PLoS One 2019; 14:e0212408. [PMID: 30779781 PMCID: PMC6380539 DOI: 10.1371/journal.pone.0212408] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Accepted: 02/02/2019] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND We characterize the risk factors for delayed polio dose 1, diphtheria-tetanus-pertussis (DTP) dose 1, pentavalent dose 1, and measles dose 1 in Ethiopian infants. We also examine the interaction between institutional delivery and demographic factors on the birth doses of the BCG and polio vaccines to better understand factors influencing vaccination. METHODS Using the 2011 Ethiopia Demographic and Health Survey, we calculated the distribution of the study population across different demographic and vaccination characteristics. We computed acceleration factors using a multivariable accelerated failure time model with a Weibull distribution to account for left and right censoring. For the birth doses, we further specified an interaction term between institutional delivery and every other a priori specified independent variable to test whether institutional delivery modifies sociodemographic disparities in vaccination timeliness. RESULTS Low wealth status, home delivery, and ethnicity are risk factors for delayed vaccination of polio 1, DPT 1, pentavalent 1, and measles 1. Religion is a risk factor for measles 1 vaccination delay and rural residence are risk factors for delayed DPT1 and polio 1 doses. For birth doses of polio and BCG, institutional delivery attenuated many sociodemographic disparities in vaccination delay, except for urbanicity, which showed rural dwellers with more delay than urban dwellers with an institutional vs home birth. CONCLUSIONS Less delayed vaccination among children with institutional deliveries highlights the importance of perinatal care and the potential for promoting healthy behaviors to parents. Persistent disparities between urban and rural residents, even among those with institutional births, can be targeted for future interventions. Timely vaccination is key to prevention of unnecessary childhood mortality.
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Affiliation(s)
- Matthew L. Boulton
- Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, Michigan, United States of America
- Department of Internal Medicine, Division of Infectious Diseases, University of Michigan Medical School, Ann Arbor, Michigan, United States of America
| | - Bradley F. Carlson
- Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Abram L. Wagner
- Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Julia M. Porth
- Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Berhanu Gebremeskel
- Center for International Reproductive Health Training, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Yemesrach Abeje
- Department of Public Health, St. Paul’s Hospital Millennium Medical College, Addis Ababa, Ethiopia
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Tsega A, Hausi H, Chriwa G, Steinglass R, Smith D, Valle M. Vaccination coverage and timely vaccination with valid doses in Malawi. ACTA ACUST UNITED AC 2016. [DOI: 10.1016/j.vacrep.2016.06.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Minh An DT, Lee JK, Van Minh H, Trang NTH, Thu Huong NT, Nam YS, Van Dung D. Timely immunization completion among children in Vietnam from 2000 to 2011: a multilevel analysis of individual and contextual factors. Glob Health Action 2016; 9:29189. [PMID: 26950555 PMCID: PMC4780107 DOI: 10.3402/gha.v9.29189] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2015] [Revised: 01/10/2016] [Accepted: 01/11/2016] [Indexed: 11/29/2022] Open
Abstract
Background Since the beginning of 2014, there have been nearly 6,000 confirmed measles cases in northern Vietnam. Of these, more than 86% had neither been immunized nor was their vaccination status confirmed. Objective To establish the likelihood that children under five in Vietnam had ‘timely immunization completion’ (2000–2011) and identify factors that account for variations in timely immunization completion. Design Secondary data from the Multiple Indicator Cluster Survey (MICS), which sampled women aged 15–49 from the 1999 Vietnamese Population and Housing Census frame, were analyzed. Multilevel analysis using Poisson regression was undertaken. Results Proportions of children under five who had timely immunization completion were low, especially for HBV dose 2 and HBV dose 3, which decreased between 2000 and 2011. Among seven vaccines used in the National Expanded Program of Immunization (EPI) in 2000, 2006, and 2011, measles dose 1 had the highest timely immunization completion at 65.3%, 66.7%, and 73.6%, respectively, and hepatitis B dose 1 had the lowest at 17.5%, 19.3%, and 45.5%, respectively. Timely immunization completion was less common among children whose mothers had relatively less household wealth, were from ethnic minorities, lived in rural areas, and had less education. At the community level, the child's region of residence was the main predictor of timely immunization completion, and the availability of hospital delivery and community prenatal care in the local community were also determinants. Conclusion The EPI should include ‘timely immunization completion’ as a quality indicator. There should also be greater focus and targeting in rural areas, and among women who have relatively low education, belong to minority groups, and have less household wealth. Further research on this topic using multilevel analysis is needed to better understand how these factors interact.
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Affiliation(s)
- Dao Thi Minh An
- Department of Epidemiology, Institute of Preventive Medicine and Public Health, Hanoi Medical University, Hanoi, Vietnam;
| | - Jong-Koo Lee
- JW LEE Center for Global Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea.,Department of Family Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea;
| | - Hoang Van Minh
- Department of Epidemiology, Institute of Preventive Medicine and Public Health, Hanoi Medical University, Hanoi, Vietnam
| | - Nguyen Thi Huyen Trang
- Department of Epidemiology, Institute of Preventive Medicine and Public Health, Hanoi Medical University, Hanoi, Vietnam
| | - Nguyen Thi Thu Huong
- Department of Epidemiology, Institute of Preventive Medicine and Public Health, Hanoi Medical University, Hanoi, Vietnam
| | - You-Seon Nam
- JW LEE Center for Global Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea.,Department of Family Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Do Van Dung
- University of Medicine and Pharmacy at Ho Chi Minh City, Ho Chi Minh City, Vietnam
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From current vaccine recommendations to everyday practices: An analysis in five sub-Saharan African countries. Vaccine 2015; 33:7290-7298. [PMID: 26546260 DOI: 10.1016/j.vaccine.2015.10.107] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Revised: 10/16/2015] [Accepted: 10/26/2015] [Indexed: 11/23/2022]
Abstract
BACKGROUND Estimates of WHO and UNICEF vaccination coverage may provide little insight into the extent to which vaccinations are administered on time. Yet, lack of adherence to the recommended age to receive a specific vaccination may have detrimental health consequences. For example, delays in receiving vaccination will prolong the risk of lack of protection, often when disease risk is highest, such as during early infancy. We estimated the reported age at vaccination, and vaccine coverage at different ages in children from five sub-Saharan African countries. METHODS We analyzed data from the latest Demographic and Health Programme databases available for Burkina Faso 2010 (n=15,044 observations), Ghana 2008 (n=2992), Kenya 2008-9 (n=6079), Senegal 2010-11 (n=12,326), and Tanzania 2010 (n=8023). We assessed, amongst vaccinees, the exact age when vaccine was administered for the three infant doses of pentavalent vaccine (DTP) and the first dose of measles-containing-vaccine (MCV), as well as the proportion of children immunized with these antigens by a certain age. Vitamin A supplementation (VAS) coverage was evaluated as a potential contact visit for vaccine introduction. RESULTS For all DTP doses, the median intervals between recommended and actual ages of receiving vaccination ranged from 12, 17 and 23 days in Kenya, to 22, 33 and 45 days in Senegal. MCV was mostly given during the recommended age of 9 months. In each country, there was a large discrepancy in the median age at DTP vaccination between regions. VAS coverage in young children ranged from 30.3% in Kenya to 78.4% in Senegal, with large variations observed between areas within each study country. CONCLUSION In the context of new vaccine introduction, age of children at vaccination should be monitored to interpret data on vaccine-preventable disease burden, vaccine effectiveness, and vaccine safety, and to adapt targeted interventions and messages.
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