{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,9]],"date-time":"2026-09-09T14:16:05Z","timestamp":1788963365342,"version":"build-2803163510"},"reference-count":45,"publisher":"AOSIS","issue":"1","license":[{"start":{"date-parts":[[2026,9,10]],"date-time":"2026-09-10T00:00:00Z","timestamp":1788998400000},"content-version":"unspecified","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"abstract":"<jats:p>Background:\u00a0The Integrated Epidemiological Surveillance System (IESS) is an essential pillar of public health, in the detection and rapid response to priority diseases. In Chad, despite its existence, the persistence of structural weaknesses influences its functioning, which justifies this study.\nAim:\u00a0This article aims to determine the current performance of the IESS in Chad, with a view to identifying possible shortcomings and proposing corrective measures.\nSetting:\u00a0An evaluative cross-sectional study was conducted from 16 September 2024 to 15 January 2025, in eight provincial health delegations in Chad.\nMethods:\u00a0The collected primary and secondary data were analysed according to the five pillars of the Centres for Disease Control and Prevention (CDC) evaluation methodology: operation, usefulness, importance, cost and quality of the IESS.\nResults:\u00a0The quality of IESS in Chad \u2013 evaluated by the CDC method \u2013 is considered low with an overall score of 44% (other pillars have been evaluated otherwise). The acceptability (87%) and simplicity (72%) of this system are its strengths. Although acceptable, the flexibility (56%) and responsiveness (55%) of the system need to be improved. The weak points that justify this low quality overall are its low sensitivity (29%) and positive predictive value (29%), as well as its very low representativeness (27%). This overall assessment seems obvious given the weaknesses identified in terms of operation, usefulness, importance and cost of IESS in Chad.\nConclusion:\u00a0The IESS in Chad remains generally functional but is of low quality.\nContribution:\u00a0This study innovates mainly because of its rigorous application of the five pillars of the CDC method for assessing the current performance of Chad\u2019s IESS in 2024.<\/jats:p>","DOI":"10.4102\/jphia.v17i1.1762","type":"journal-article","created":{"date-parts":[[2026,9,9]],"date-time":"2026-09-09T13:54:54Z","timestamp":1788962094000},"update-policy":"https:\/\/doi.org\/10.4102\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Evaluation of the Integrated Epidemiological Surveillance System in Chad according to the CDC method"],"prefix":"10.4102","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0009-0002-6086-3732","authenticated-orcid":false,"given":"Kallah","family":"Boukar Ousmane","sequence":"first","affiliation":[{"id":[{"id":"https:\/\/ror.org\/03gzr6j88","id-type":"ROR","asserted-by":"publisher"}],"name":"Universit\u00e9 d'Abomey-Calavi"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4958-7722","authenticated-orcid":false,"given":"Moussiliou No\u00ebl","family":"Para\u00efso","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/03gzr6j88","id-type":"ROR","asserted-by":"publisher"}],"name":"Universit\u00e9 d'Abomey-Calavi"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-6141-4607","authenticated-orcid":false,"given":"Harold","family":"Dossou Yovo","sequence":"additional","affiliation":[{"name":"Africa Synergy Group Plus (ASGPLUS), Cotonou, Benin"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-6219-0430","authenticated-orcid":false,"given":"Oloumane","family":"Dyvail Junior","sequence":"additional","affiliation":[{"name":"Africa Synergy Group Plus (ASGPLUS), Cotonou, Benin"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-9793-1722","authenticated-orcid":false,"given":"Patrice","family":"Zekeng","sequence":"additional","affiliation":[{"name":"Africa Synergy Group Plus (ASGPLUS), Cotonou, Benin"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"2580","published-online":{"date-parts":[[2026,9,10]]},"reference":[{"key":"ref0","unstructured":"World Health Organization. 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Available from: https:\/\/www.who.int\/"}],"container-title":["Journal of Public Health in Africa"],"original-title":[],"deposited":{"date-parts":[[2026,9,9]],"date-time":"2026-09-09T13:55:12Z","timestamp":1788962112000},"score":1,"resource":{"primary":{"URL":"https:\/\/publichealthinafrica.org\/index.php\/jphia\/article\/view\/1762"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,9,10]]},"references-count":45,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2026,1,1]]}},"URL":"https:\/\/doi.org\/10.4102\/jphia.v17i1.1762","relation":{},"ISSN":["2038-9922","2038-9930"],"issn-type":[{"value":"2038-9922","type":"print"},{"value":"2038-9930","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,9,10]]},"article-number":"a1762"}}