大流行性流感严重程度评估（PISA）：世界卫生组织评估季节性流行病和大流行中流感严重程度的指南，第二版

A WHO guide to assess the severityof influenza in seasonal epidemicsand pandemics, second edition Pandemic influenzaseverity assessment (PISA) A WHO guide to assess the severityof influenza in seasonal epidemicsand pandemics, second edition Pandemic influenza severity assessment (PISA): a WHO guide to assess the severity of influenza in seasonal epidemicsand pandemics, second edition ISBN 978-92-4-009388-1 (electronic version)ISBN 978-92-4-009389-8 (print version) © World Health Organization 2024 Some rights reserved. This work is available under the Creative Commons Attribution-NonCommercial-ShareAlike 3.0 IGOlicence (CC BY-NC-SA 3.0 IGO;https://creativecommons.org/licenses/by-nc-sa/3.0/igo). Under the terms of this licence, you may copy, redistribute and adapt the work for non-commercial purposes, providedthe work is appropriately cited, as indicated below. In any use of this work, there should be no suggestion that WHOendorses any specific organization, products or services. The use of the WHO logo is not permitted. If you adapt the work,then you must license your work under the same or equivalent Creative Commons licence. If you create a translation ofthis work, you should add the following disclaimer along with the suggested citation:“This translation was not created bythe World Health Organization (WHO). WHO is not responsible for the content or accuracy of this translation. The originalEnglish edition shall be the binding and authentic edition”. Any mediation relating to disputes arising under the licence shall be conducted in accordance with the mediation rules ofthe World Intellectual Property Organization (http://www.wipo.int/amc/en/mediation/rules/). Suggested citation. Pandemic influenza severity assessment (PISA): a WHO guide to assess the severity of influenzain seasonal epidemics and pandemics, second edition. Geneva: World Health Organization; 2024. Licence:CC BY-NC-SA 3.0 IGO. Cataloguing-in-Publication (CIP) data.CIP data are available athttps://iris.who.int/. Sales, rights and licensing.To purchase WHO publications, seehttps://www.who.int/publications/book-orders. Tosubmit requests for commercial use and queries on rights and licensing, seehttps://www.who.int/copyright. Third-party materials.If you wish to reuse material from this work that is attributed to a third party, such as tables,figures or images, it is your responsibility to determine whether permission is needed for that reuse and to obtainpermission from the copyright holder. The risk of claims resulting from infringement of any third-party-owned componentin the work rests solely with the user. General disclaimers.The designations employed and the presentation of the material in this publication do not implythe expression of any opinion whatsoever on the part of WHO concerning the legal status of any country, territory, city orarea or of its authorities, or concerning the delimitation of its frontiers or boundaries. Dotted and dashed lines on mapsrepresent approximate border lines for which there may not yet be full agreement. The mention of specific companies or of certain manufacturers’ products does not imply that they are endorsed orrecommended by WHO in preference to others of a similar nature that are not mentioned. Errors and omissions excepted,the names of proprietary products are distinguished by initial capital letters. All reasonable precautions have been taken by WHO to verify the information contained in this publication. However, thepublished material is being distributed without warranty of any kind, either expressed or implied. The responsibility for theinterpretation and use of the material lies with the reader. In no event shall WHO be liable for damages arising from its use. Contents 2Aim of the influenza severity assessment3Influenza severity assessment concept and definitions3.1 Indicators3.1.1Transmissibility3.1.2Seriousness of disease3.1.3Morbidity and mortality3.1.4Impact on health care capacity3.2 Parameters 566677811 4Steps for assessing influenza severity124.1 Step 1: Choose the parameters that will be used to assess each indicator124.2 Step 2: Set the thresholds for each parameter using historical data194.2.1Principles of threshold setting194.2.2Thresholds for transmissibility, and morbidity and mortality parameters204.2.3Thresholds for impact on health care capacity parameters204.2.4Thresholds for seriousness of disease parameters224.3 Step 3: Interpret data to assess severity234.4 Step 4: Communicate and report the severity assessment findings254.4.1Communicating PISA results254.4.2Reporting PISA results to WHO26 5Presentation and use of severity assessments at the global level286References30Annex. Data collection agreement31 Figures Figure 1. PISA development timeline2Figure 2. Example of how to interpret PISA scores together with contextual information to generate anindicator score24Figure 3. Heat chart for transmissibility indicator29 Tables Table 1. Changes made in this