Human African trypanosomiasis


Research in diagnosis

© ahibadi

The most significant progress in diagnostics occurred in the late 1970 when the Card Agglutination Trypanosomiasis Test (CATT) was developed for serological screening. Unfortunately CATT is only applicable to T.b. gambiense infections. Since the 1980s the test has been progressively used for screening the population at risk in west and central Africa where the Gambiense form of the disease is prevalent. As no major advances were made since, CATT remains today the only serological test available.

For effective control and surveillance of sleeping sickness, new tests are needed. New diagnostic tests should be affordable, implementable with simple protocols at any health structure level requiring minimum training and equipment, allowing its easy execution by any health worker.

It should provide rapid and reliable results with optimal sensitivity and specificity, for an uncontroversial diagnosis of both forms of the disease. This should enable onset of immediate treatment, avoiding cumbersome parasitological examinations.

In addition, the tests should be stable at room temperature, requiring no refrigeration and having a reasonable volume for easy storage and transport.

Improved tests for staging are also needed. Stage markers in other body fluids such as serum, urine, or saliva would be ideal to avoid the invasive procedure of a lumbar puncture.

WHO HAT Specimen Bank

As part of its contribution to support diagnostics research, WHO has set up a HAT specimen bank. This makes biological samples of patients, endemic controls and serological suspects of HAT available to Research Institutions working for the development of new diagnostic tests or therapeutic tools. The aim of the specimen bank is to provide reference clinical materials to research institutions to develop and evaluate new tests for diagnosis and staging of HAT, appropriate for use in low-income countries.
Requests of samples should be made to :

Dr Gerardo Priotto
Department of Control of Neglected Tropical Diseases
World Health Organization
Telephone: +41 22 791 1375

Dr Jose Ramon Franco
Department of Control of Neglected Tropical Diseases
World Health Organization
Telephone: +41 22 791 3313

Request form for samples

Research in treatment

Sleeping sickness is notoriously difficult to treat considering toxicity and protocol complexity of the drugs currently available for treatment. Furthermore, in the last years, parasite resistance to existing drugs has started to appear and the lack of new molecules to treat the disease has become a major issue.

New molecules

Developing a new drug to treat sleeping sickness is necessary. The development of Pafuramidine maleate (DB289), was interrupted in February 2008. Preclinical studies of a new molecule, fexinidazole, are now complete and a clinical trial phase I is ongoing.

Fexinidazole is a nitroimidazole which has showed its efficacy at preclinical stage. It is being investigated for possible future use as an oral drug in early and late stages of both forms of HAT.

Human African trypanosomiasis in the news

16 April 2016 | Geneva
Lowest caseload recorded as the world prepares to defeat sleeping sickness.
The World Health Organization targets the elimination of this commonest form of the disease as a 'public health problem' by 2020.

30 July 2015 | Geneva
Report of the first WHO stakeholders meeting on rhodesiense human African trypanosomiasis Geneva, 20–22 October 2014
Ref: ISBN 978 92 4 150865 0

01 June 2015 | Geneva
WHO network for HAT elimination
Human African trypanosomiasis: update of the methodological framework for clinical trials
Ref: ISBN 978 92 4 150883 4

19 May 2015 | Geneva
Cases of sleeping sickness drop to lowest level in 75 years

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