title: Key data for outbreak evaluation: building on the Ebola experience.
abstract: Following the detection of an infectious disease outbreak, rapid epidemiological assessment is critical for guiding an effective public health response. To understand the transmission dynamics and potential impact of an outbreak, several types of data are necessary. Here we build on experience gained in the West African Ebola epidemic and prior emerging infectious disease outbreaks to set out a checklist of data needed to: (1) quantify severity and transmissibility; (2) characterize heterogeneities in transmission and their determinants; and (3) assess the effectiveness of different interventions. We differentiate data needs into individual-level data (e.g. a detailed list of reported cases), exposure data (e.g. identifying where/how cases may have been infected) and population-level data (e.g. size/demographics of the population(s) affected and when/where interventions were implemented). A remarkable amount of individual-level and exposure data was collected during the West African Ebola epidemic, which allowed the assessment of (1) and (2). However, gaps in population-level data (particularly around which interventions were applied when and where) posed challenges to the assessment of (3). Here we highlight recurrent data issues, give practical suggestions for addressing these issues and discuss priorities for improvements in data collection in future outbreaks.This article is part of the themed issue 'The 2013-2016 West African Ebola epidemic: data, decision-making and disease control'.
authors.affiliation: Medical Research Council Centre for Outbreak Analysis and Modelling, Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, London W2 1PG, UK.
authors.forename: Anne
authors.identifier: http://orcid.org/0000-0002-8443-9162
authors.initials: A
authors.lastname: Cori
authors.affiliation: Medical Research Council Centre for Outbreak Analysis and Modelling, Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, London W2 1PG, UK.
authors.forename: Christl A
authors.identifier: http://orcid.org/0000-0002-0195-2463
authors.initials: CA
authors.lastname: Donnelly
authors.affiliation: Medical Research Council Centre for Outbreak Analysis and Modelling, Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, London W2 1PG, UK.
authors.forename: Ilaria
authors.initials: I
authors.lastname: Dorigatti
authors.affiliation: Medical Research Council Centre for Outbreak Analysis and Modelling, Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, London W2 1PG, UK.
authors.forename: Neil M
authors.initials: NM
authors.lastname: Ferguson
authors.affiliation: Oxford Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7FZ, UK.
authors.forename: Christophe
authors.initials: C
authors.lastname: Fraser
authors.affiliation: Medical Research Council Centre for Outbreak Analysis and Modelling, Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, London W2 1PG, UK.
authors.forename: Tini
authors.identifier: http://orcid.org/0000-0002-8952-4710
authors.initials: T
authors.lastname: Garske
authors.affiliation: Medical Research Council Centre for Outbreak Analysis and Modelling, Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, London W2 1PG, UK.
authors.forename: Thibaut
authors.initials: T
authors.lastname: Jombart
authors.affiliation: Medical Research Council Centre for Outbreak Analysis and Modelling, Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, London W2 1PG, UK.
authors.forename: Gemma
authors.identifier: http://orcid.org/0000-0001-5723-5028
authors.initials: G
authors.lastname: Nedjati-Gilani
authors.affiliation: Medical Research Council Centre for Outbreak Analysis and Modelling, Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, London W2 1PG, UK.
authors.forename: Pierre
authors.initials: P
authors.lastname: Nouvellet
authors.affiliation: Medical Research Council Centre for Outbreak Analysis and Modelling, Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, London W2 1PG, UK.
authors.forename: Steven
authors.initials: S
authors.lastname: Riley
authors.affiliation: Centre for Global Health, Institut Pasteur, 25-28 Rue du Dr Roux, 75015 Paris, France.
authors.forename: Maria D
authors.initials: MD
authors.lastname: Van Kerkhove
authors.affiliation: Medical Research Council Centre for Outbreak Analysis and Modelling, Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, London W2 1PG, UK harriet.l.mills@gmail.com.|MRC Integrative Epidemiology Unit, School of Social and Community Medicine, University of Bristol, Bristol BS8 2BN, UK.|School of Veterinary Sciences, University of Bristol, Bristol BS40 5DU, UK.
authors.forename: Harriet L
authors.initials: HL
authors.lastname: Mills
authors.affiliation: Medical Research Council Centre for Outbreak Analysis and Modelling, Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, London W2 1PG, UK.
authors.forename: Isobel M
authors.identifier: http://orcid.org/0000-0002-3977-1318
authors.initials: IM
authors.lastname: Blake
mesh_terms: D000354:Africa, Western / Q000453:epidemiology; D057189:Checklist; D021821:Communicable Diseases, Emerging / Q000453:epidemiology / Q000517:prevention & control / Q000635:transmission / Q000821:virology; D058872:Epidemics / Q000517:prevention & control; D019142:Hemorrhagic Fever, Ebola / Q000453:epidemiology / Q000517:prevention & control / Q000635:transmission / Q000821:virology; D006801:Humans; D011634:Public Health
keywords: West African Ebola epidemic; data; epidemic; mathematical modelling; outbreak response; public health