Estimates of the duration of the early and late stage of gambiense sleeping sickness.
Affiliation
Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E7HT, UK. francesco.checchi@lshtm.ac.ukIssue Date
2008-02-08
Metadata
Show full item recordJournal
BMC Infectious DiseasesAbstract
BACKGROUND: The durations of untreated stage 1 (early stage, haemo-lymphatic) and stage 2 (late stage, meningo-encephalitic) human African trypanosomiasis (sleeping sickness) due to Trypanosoma brucei gambiense are poorly quantified, but key to predicting the impact of screening on transmission. Here, we outline a method to estimate these parameters. METHODS: We first model the duration of stage 1 through survival analysis of untreated serological suspects detected during Médecins Sans Frontières interventions in Uganda and Sudan. We then deduce the duration of stage 2 based on the stage 1 to stage 2 ratio observed during active case detection in villages within the same sites. RESULTS: Survival in stage 1 appears to decay exponentially (daily rate = 0.0019; mean stage 1 duration = 526 days [95%CI 357 to 833]), possibly explaining past reports of abnormally long duration. Assuming epidemiological equilibrium, we estimate a similar duration of stage 2 (500 days [95%CI 345 to 769]), for a total of nearly three years in the absence of treatment. CONCLUSION: Robust estimates of these basic epidemiological parameters are essential to formulating a quantitative understanding of sleeping sickness dynamics, and will facilitate the evaluation of different possible control strategies.Publisher
BioMed CentralPubMed ID
18261232Language
enISSN
1471-2334ae974a485f413a2113503eed53cd6c53
10.1186/1471-2334-8-16
Scopus Count
Collections
Related articles
- Updated estimate of the duration of the meningo-encephalitic stage in gambiense human African trypanosomiasis.
- Authors: Checchi F, Funk S, Chandramohan D, Haydon DT, Chappuis F
- Issue date: 2015 Jul 4
- The impact of passive case detection on the transmission dynamics of gambiense Human African Trypanosomiasis.
- Authors: Checchi F, Funk S, Chandramohan D, Chappuis F, Haydon DT
- Issue date: 2018 Apr
- [Trypanosomiasis from Trypanosoma brucei gambiense in the center of north-west Uganda. Evaluation of 5 years of control (1987-1991)].
- Authors: Paquet C, Castilla J, Mbulamberi D, Beaulieu MF, Gastellu Etchegorry MG, Moren A
- Issue date: 1995
- Accuracy of five algorithms to diagnose gambiense human African trypanosomiasis.
- Authors: Checchi F, Chappuis F, Karunakara U, Priotto G, Chandramohan D
- Issue date: 2011 Jul
- Sleeping sickness in Uganda: a thin line between two fatal diseases.
- Authors: Picozzi K, Fèvre EM, Odiit M, Carrington M, Eisler MC, Maudlin I, Welburn SC
- Issue date: 2005 Nov 26