Treatment and control of human African trypanosomiasis.
OBJECTIVE
Access to treatment is a multi-step process and little progress has been made to improve treatments for sleeping sickness over the past 50 years. The current strategy is based on diagnostic tools developed in the 1960s while available drugs are still the same as those developed in the middle of the last century. Strategic opportunities can only be based on two achievements: improved diagnosis and safer drugs. This paper reviews the development of new diagnostic tools and drugs and the opportunity offered by new technologies for their further improvement.


RESULTS
The prodrug DB289 shows excellent oral activity with low toxicity for the treatment of early-stage sleeping sickness; it has recently entered phase II(b) clinical trials. The recent ability to identify and test specific host and parasite biomarkers has allowed the development of new, more-specific and sensitive, diagnostic and stage-determination tools. The accurate diagnosis of an infection by use of proteomic signature analysis has been achieved. Urinary nitrites and nitrates follow closely the increase of brain nitric oxide associated with the penetration of trypanosomes in the brain. Sleep-onset rapid eye movement-like episodes have been shown to occur at onset of late-stage trypanosomiasis. This unique disturbance of the wake/sleep cycle seems to be the first pathognomonic sign in the occurrence of late-stage trypanosomiasis.


CONCLUSIONS
Following the description of the disease, and diagnostic tools and drugs that have been used, and are still in use today, the authors show how it has influenced over time the evolution of strategies for surveillance and control. Recent developments and prospects for new, more-specific and sensitive diagnostic tools and a safer drug will undoubtedly improve the accuracy of patient recruitment and facilitate treatment, and provide ways towards new strategic opportunities.
Jannin
J
J
World Health Organization, 1211 Geneva, Switzerland. janninj@who.int
Cattand
P
P
D000818:Animals; D001550:Benzamidines / Q000493:pharmacokinetics / Q000627:therapeutic use; D015415:Biomarkers; D006801:Humans; D014344:Trypanocidal Agents / Q000627:therapeutic use*; D014347:Trypanosoma brucei gambiense / Q000187:drug effects; D016833:Trypanosoma brucei rhodesiense / Q000187:drug effects; D014353:Trypanosomiasis, African / Q000175:diagnosis / Q000188:drug therapy* / Q000517:prevention & control*
D001550:Benzamidines; D015415:Biomarkers; D014344:Trypanocidal Agents; C458513:pafuramidine