The effect of time since measles vaccination and age at first dose on measles vaccine effectiveness - A systematic review

• Authors: Stephanie L. Hughes, Public Health Ontario; Shelly Bolotin, University of Toronto; Sumaiya Khan, Public Health Ontario; Ye Li, Public Health Ontario; Caitlin Johnson, Public Health Ontario; Lindsay Friedman, Public Health Ontario; Andrea C. Tricco, University of Toronto; Susan J. M. Hahne, Centre for Infectious Disease Control, National Institute for Public Health and the Environment, Bilthoven, the Netherlands; Jane M. Heffernan, York University; Alya Dabbagh, World Health Organization; David N. Durrheim, University of Newcastle; Walter Orenstein, Emory University; William J. Moss, Johns Hopkins University; Mark Jit, London School of Hygiene & Tropical Medicine; Natasha S. Crowcroft, University of Toronto
• Journal Title: Vaccine
• Volume: Volume 38, Number 3
• Publisher: Elsevier Science Ltd. | 2020-01-16, Pages 460-469
• Type of Work: Article | Final Publisher PDF
• Publisher DOI: http://doi.org/10.1016/j.vaccine.2019.10.090
• Subjects: Health Sciences, Immunology; Health Sciences, Epidemiology; Health Sciences, Public Health; Health Sciences, Pharmacy
• Keywords: Science & Technology; Life Sciences & Biomedicine; Immunology; Medicine, Research & Experimental; Research & Experimental Medicine; Measles; Vaccine effectiveness; Waning immunity; Eliminated; Endemic; Immunisation; Immunization strategies; Antibody levels; Epidemics; Efficacy; Outbreak; Children; Elimination; Immunity; Population; Standard

Abstract

Background: In settings where measles has been eliminated, vaccine-derived immunity may in theory wane more rapidly due to a lack of immune boosting by circulating measles virus. We aimed to assess whether measles vaccine effectiveness (VE) waned over time, and if so, whether differentially in measles-eliminated and measles-endemic settings. Methods: We performed a systematic literature review of studies that reported VE and time since vaccination with measles-containing vaccine (MCV). We extracted information on case definition (clinical symptoms and/or laboratory diagnosis), method of vaccination status ascertainment (medical record or vaccine registry), as well as any biases which may have arisen from cold chain issues and a lack of an age at first dose of MCV. We then used linear regression to evaluate VE as a function of age at first dose of MCV and time since MCV. Results: After screening 14,782 citations, we identified three full-text articles from measles-eliminated settings and 33 articles from measles-endemic settings. In elimination settings, two-dose VE estimates increased as age at first dose of MCV increased and decreased as time since MCV increased; however, the small number of studies available limited interpretation. In measles-endemic settings, one-dose VE increased by 1.5% (95% CI 0.5, 2.5) for every month increase in age at first dose of MCV. We found no evidence of waning VE in endemic settings. Conclusions: The paucity of data from measles-eliminated settings indicates that additional studies and approaches (such as studies using proxies including laboratory correlates of protection) are needed to answer the question of whether VE in measles-eliminated settings wanes. Age at first dose of MCV was the most important factor in determining VE. More VE studies need to be conducted in elimination settings, and standards should be developed for information collected and reported in such studies.