Update of transmission modelling and projections of gambiense human African trypanosomiasis in the Mandoul focus, Chad  

作　　者：Kat S.Rock Ching-I Huang Ronald E.Crump Paul R.Bessell Paul E.Brown Inaki Tirados Philippe Solano Marina Antillon Albert Picado Severin Mbainda Justin Darnas Emily H.Crowley Steve J.Torr Mallaye Peka 

机构地区：[1]Mathematics Institute,University of Warwick,Academic Loop Road,Coventry,CV47AL,UK [2]Zeeman Institute for Systems Biology&Infectious Disease Epidemiology Research(SBIDER),University of Warwick,Academic Loop Road,Coventry,CV47AL,UK [3]Independent Consultant,Edinburgh,UK [4]Department of Vector Biology,Liverpool School of Tropical Medicine,Liverpool,UK [5]Institut de Recherche pour le Développement,UMR INTERTRYP IRD-CIRAD,Universitéde Montpellier,34398,Montpellier,France [6]Swiss Tropical and Public Health Institute,Basel,Switzerland [7]University of Basel,Basel,Switzerland [8]Foundation for Innovative New Diagnostics(FIND),Geneva,Switzerland [9]Programme National de Lutte contre la Trypanosomiase Humaine Africaine(PNLTHA),Moundou,Chad

出　　处：《Infectious Diseases of Poverty》2022年第1期34-46,共13页贫困所致传染病（英文）

基　　金：This work was supported by the Bill and Melinda Gates Foundation(www.gatesfoundation.org)through the Human African Trypanosomiasis Modelling and Economic Predictions for Policy(HAT MEPP)project[OPP1177824 and INV-005121](CH,REC,PEB,MA,EHC,KSR);through the NTD Modelling Consortium[OPP1184344](KSR),and the Trypa-NO!project[INV-008412 and INV-001785](PRB,AP,SJT,PS and IT);SJT received funding from the Biotechnology and Biological Sciences Research Council(www.bbsrc.ukri.org;Grants BB/S01375X/1,BB/S00243X/1,BB/P005888/1).The funders had no role in study design,data collection and analysis,decision to publish,or preparation of the manuscript.

摘　　要：Background:In recent years,a programme of vector control,screening and treatment of gambiense human African trypanosomiasis(gHAT)infections led to a rapid decline in cases in the Mandoul focus of Chad.To represent the biology of transmission between humans and tsetse,we previously developed a mechanistic transmission model,fitted to data between 2000 and 2013 which suggested that transmission was interrupted by 2015.The present study outlines refinements to the model to:(1)Assess whether elimination of transmission has already been achieved despite low-level case reporting;(2)quantify the role of intensified interventions in transmission reduction;and(3)predict the trajectory of gHAT in Mandoul for the next decade under different strategies.Method:Our previous gHAT transmission model for Mandoul was updated using human case data(2000-2019)and a series of model refinements.These include how diagnostic specificity is incorporated into the model and improvements to the fitting method(increased variance in observed case reporting and how underreporting and improvements to passive screening are captured).A side-by-side comparison of fitting to case data was performed between the models.Results:We estimated that passive detection rates have increased due to improvements in diagnostic availability in fixed health facilities since 2015,by 2.1-fold for stage 1 detection,and 1.5-fold for stage 2.We find that whilst the diagnostic algorithm for active screening is estimated to be highly specific(95%credible interval(CI):99.9-100%,Specificity=99.9%),the high screening and low infection levels mean that some recently reported cases with no parasitological confirmation might be false positives.We also find that the focus-wide tsetse reduction estimated through model fitting(95%CI:96.1-99.6%,Reduction=99.1%)is comparable to the reduction previously measured by the decline in tsetse catches from monitoring traps.In line with previous results,the model suggests that transmission was interrupted in 2015 due to intensified interven

关 键 词：Gambiense human AFRICAN TRYPANOSOMIASIS (gHAT) Modelling ELIMINATION of transmission Validation TSETSE Vector control GLOSSINA Diagnostics 

分 类 号：R531[医药卫生—内科学] R181.3[医药卫生—临床医学]