Please cite this article in press as: Clouston S, et al. Social inequalities in vaccination uptake among children aged 0–59 months living in Madagascar: An analysis of Demographic and Health Survey data from 2008 to 2009. Vaccine (2014), http://dx.doi.org/10.1016/j.vaccine.2014.04.030 ARTICLE IN PRESS G Model JVAC-15311; No. of Pages 7 Vaccine xxx (2014) xxx–xxx Contents lists available at ScienceDirect Vaccine j our na l ho me page: www.elsevier.com/locate/vaccine Social inequalities in vaccination uptake among children aged 0–59 months living in Madagascar: An analysis of Demographic and Health Survey data from 2008 to 2009 S. Clouston ∗ , R. Kidman, T. Palermo Department of Preventive Medicine & Program in Public Health, Stony Brook University, United States a r t i c l e i n f o Article history: Received 19 November 2013 Received in revised form 4 April 2014 Accepted 14 April 2014 Available online xxx Keywords: Global health Social inequalities and health Vaccine coverage Herd immunity Madagascar Geographic variation Multilevel analysis a b s t r a c t Background: Socioeconomic inequalities in vaccination can reduce the ability and efficiency of global efforts to reduce the burden of disease. Vaccination is particularly critical because the poorest children are often at the greatest risk of contracting preventable infectious diseases, and unvaccinated children may be clustered geographically, jeopardizing herd immunity. Without herd immunity, these children are at even greater risk of contracting disease and social inequalities in associated morbidity and mortality are amplified. Methods: Data on vaccination for children under five came from the most recent Demographic and Health Survey in Madagascar (2008–2009). Vaccination status was available for diptheria, pertussis, tetanus, hepatitis B, measles, tuberculosis, poliomyelitis, and H. influenza type-B. Multilevel logistic regression was used to analyze childhood vaccination by parental socioeconomic status while accounting for shared district, cluster, and household variation. Maps were created to serve as a roadmap for efforts to increase vaccination. Findings: Geographic variation in vaccination rates was substantial. Districts that were less covered were near other districts with limited coverage. Most districts lacked herd immunity for diphtheria, pertussis, poliomyelitis and measles. Full herd immunity was reached in a small number of districts clustered near the capital. While within-district variation in coverage was substantial; parental education and wealth were independently associated with vaccination. Interpretation: Socioeconomic inequalities in vaccination reduce herd immunity and perpetuate inequali- ties by allowing infectious diseases to disproportionately affect the most vulnerable populations. Findings indicated that most districts had low immunization coverage rates and unvaccinated children were geographically clustered. The result was inequalities in vaccination and reduced herd immunity. To fur- ther improve coverage, interventions must take a multilevel approach that focuses on both supply- and demand-side barriers to delivering vaccination to underserved regions, and to the poorest children in those regions. © 2014 Elsevier Ltd. All rights reserved. Abbreviations: SES, socioeconomic status; GVAP, global vaccination action plan; EPI, World Health Organization’s expanded program on immunization; DPT, quadrivalent diphtheriatetanus,pertussis and hepatitis B vaccine; HiB, haemophilus influenza type-B vaccine; MLLM, multi-level logistic modeling. ∗ Corresponding author at: Stony Brook University, Program in Public Health, Health Sciences Center 3-071, Stony Brook, NY 11794-8338, United States. Tel.: +1 631 444 6593; fax: +1 631 444 3480. E-mail addresses: sean.clouston@stonybrookmedicine.edu, saclous@uvic.ca (S. Clouston). 1. Background 1.1. Social inequalities in vaccination There have been improvements in childhood immunization in recent years: the World Health Organization (WHO) estimates routine vaccinations now avert between two and three mil- lion deaths annually [1]. However gains have not been equally distributed: immunization coverage in developed countries far out- paces that in less developed countries (96–81%, respectively) [2]. Research also suggests that even among countries showing marked improvement, national averages may mask differences or increas- ing inequalities within a country [3,4]. For example, children whose http://dx.doi.org/10.1016/j.vaccine.2014.04.030 0264-410X/© 2014 Elsevier Ltd. All rights reserved.