{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T11:20:00Z","timestamp":1790162400548,"version":"4.1.0"},"reference-count":26,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2025,12,1]],"date-time":"2025-12-01T00:00:00Z","timestamp":1764547200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2026,1,5]],"date-time":"2026-01-05T00:00:00Z","timestamp":1767571200000},"content-version":"vor","delay-in-days":35,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"DOI":"10.13039\/100000865","name":"Bill and Melinda Gates Foundation","doi-asserted-by":"publisher","award":["INV-005121"],"award-info":[{"award-number":["INV-005121"]}],"id":[{"id":"10.13039\/100000865","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000865","name":"Bill and Melinda Gates Foundation","doi-asserted-by":"publisher","award":["INV-005121"],"award-info":[{"award-number":["INV-005121"]}],"id":[{"id":"10.13039\/100000865","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000865","name":"Bill and Melinda Gates Foundation","doi-asserted-by":"publisher","award":["INV-005121"],"award-info":[{"award-number":["INV-005121"]}],"id":[{"id":"10.13039\/100000865","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Parasites Vectors"],"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>\n                    Modelling is an effective and widely used tool for predicting the future trajectory of infectious diseases. One of its strengths is its ability to measure and predict metrics that are unobservable in real life, such as the true prevalence, or when infection events occur. Policy goals, on the other hand, must necessarily be based on observable metrics in order to be verifiable. The WHO has targeted\n                    <jats:italic>gambiense<\/jats:italic>\n                    human African trypanosomiasis (\n                    <jats:italic>g<\/jats:italic>\n                    HAT) for elimination of transmission (EoT) by 2030. In order to verify this, the WHO HAT Elimination Technical Advisory Group (HAT-e-TAG) has recently defined the country-level indicator for EoT as 5 years of no new locally-infected reported cases, along with a sufficient level of surveillance. While this indicator is a useful and concrete metric that can be clearly measured, it does not directly measure the actual transmission or prevalence of the disease. In some cases, the timing of the last transmission event or the point when infection is no longer present in a country may differ quite substantially from when the country reaches the WHO indicator for EoT. In this article, we discuss the difference between these different metrics and show with some examples how much they can disagree. Furthermore, modelling papers have previously been published using various approximations of EoT, which has the potential to cause confusion. In this paper, we highlight the potential misunderstandings which could occur due to seemingly trivial differences in the definition of elimination and its indicators, especially in the context of such a slow-progressing disease as gHAT. We conclude that while there is value in models predicting both observable and unobservable metrics, modellers need to ensure that they are clear about definitions when communicating results, and policymakers need to be sure that they know what definitions are being used when drawing conclusions from model results. While this paper focuses specifically on three indicators of EoT for gHAT, the general points made here could have applications in other infections approaching the endgame, such as onchocerciasis, or even beyond public health.\n                  <\/jats:p>\n                  <jats:p>\n                    <jats:bold>Graphical Abstract<\/jats:bold>\n                  <\/jats:p>","DOI":"10.1186\/s13071-025-07131-0","type":"journal-article","created":{"date-parts":[[2025,12,1]],"date-time":"2025-12-01T15:58:47Z","timestamp":1764604727000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Measuring elimination of gambiense human African trypanosomiasis: a comparison of deceptively different metrics"],"prefix":"10.1186","volume":"19","author":[{"given":"Samuel A.","family":"Sutherland","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jason J.","family":"Madan","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kat S.","family":"Rock","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2025,12,1]]},"reference":[{"key":"7131_CR1","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pntd.0001691","volume":"6","author":"V Jamonneau","year":"2012","unstructured":"Jamonneau V, Ilboudo H, Kabor\u00e9 J, Kaba D, Koffi M, Solano P, et al. Untreated human infections by Trypanosoma brucei gambiense are not 100% fatal. PLoS Negl Trop Dis. 2012;6:e1691.","journal-title":"PLoS Negl Trop Dis"},{"key":"7131_CR2","unstructured":"WHO. Sustaining the drive to overcome the global impact of neglected tropical diseases: second WHO report on neglected diseases. WHO\/HTM\/NTD\/2013.1. Geneva: World Health Organization; 2013. https:\/\/www.who.int\/publications\/i\/item\/9789241564540. Accessed 12 Nov 2025."},{"key":"7131_CR3","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pntd.0010047","volume":"16","author":"JR Franco","year":"2022","unstructured":"Franco JR, Cecchi G, Paone M, Diarra A, Grout L, Kadima Ebeja A, et al. The elimination of human African trypanosomiasis: achievements in relation to WHO road map targets for 2020. 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No new data collection took place within the scope of this modelling study.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethics approval and consent to participate"}},{"value":"Not applicable.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Consent for publication"}},{"value":"The authors and their research group (HAT MEPP) collaborate with some members of the WHO HAT-e-TAG as part of their work with respect to HAT elimination, and KSR and SAS have also attended WHO HAT Stakeholder meetings. HAT MEPP have had no influence on the process of defining the WHO indicator of elimination of transmission and do not receive any direct reimbursement from any employees of the WHO or members of the HAT-e-TAG but some members of the HAT-e-TAG are also funded by the Gates Foundation under their respective projects. The HAT-e-TAG had no influence on the analysis in this paper, although members of the HAT-e-TAG were amongst those asked for their opinion on selecting the name for the indicator we called \"Last transmission event\". Additionally, the final draft of the paper was shared with the WHO HAT team as a courtesy since, while this paper does not directly use data from the HAT Atlas, the team did provide the data which was used to generate the parameterisations (previously published) which we used in this paper.","order":4,"name":"Ethics","group":{"name":"EthicsHeading","label":"Competing interests"}}],"article-number":"8"}}