title: Real-time investigation of measles epidemics with estimate of vaccine efficacy.
abstract: As part of measles elimination effort, evaluation of the vaccination program and real-time assessment of the epidemic dynamics constitute two important tasks to improve and strengthen the control. The present study aimed to develop an epidemiological modeling method which can be applied to estimating the vaccine efficacy at an individual level while conducting the timely investigation of the epidemic. The multivariate renewal process model was employed to describe the temporal evolution of infection by vaccination history, jointly estimating the time-dependent reproduction number and the vaccine efficacy. Analyzing the enhanced surveillance data of measles in Aichi prefecture, Japan from 2007-08, the vaccine efficacy was estimated at 96.7% (95% confidence interval: 95.8, 97.4). Using an age structured model, the vaccine efficacy among those aged from 5-19 years was shown to be smaller than that among those from 0-4 years. The age-dependent vaccine efficacy estimate informs the age-groups to be targeted for revaccination. Because the estimation method can rest on readily available epidemiological data, the proposed model has a potential to be integrated with routine surveillance.
authors.affiliation: Department of Mathematical Informatics, Graduate School of Information Science and Technology, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
authors.forename: Keisuke
authors.initials: K
authors.lastname: Ejima
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Omori
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Aihara
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Nishiura
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D004196:Disease Outbreaks / Q000517:prevention & control; D006801:Humans; D007115:Immunization Schedule; D007223:Infant; D007564:Japan / Q000453:epidemiology; D008457:Measles / Q000453:epidemiology* / Q000517:prevention & control; D008458:Measles Vaccine / Q000276:immunology* / Q000592:standards; D018448:Models, Immunological; D014611:Vaccination / Q000706:statistics & numerical data
chemical_list: D008458:Measles Vaccine