African Journal of Biotechnology Vol. 1 (2), pp. 39-45, December 2002

ISSN 1684-5315  © 2002 Academic Journals  

The diagnosis of trypanosome infections: applications of novel technology for reducing disease risk

Picozzi, K.¹, Tilley, A.¹, Fèvre, E.M.¹, Coleman, P.G.¹, Magona, J.W.², Odiit, M.², Eisler, M.C³ and Welburn S.C.^1*

¹Centre for Tropical Veterinary Medicine, Royal (Dick) School of Veterinary Studies, The University of Edinburgh, Easter Bush, Roslin, Midlothian, Scotland, EH25 9RG, UK

²Livestock Health Research Institute, PO Box 96, Tororo, Uganda

³University of Glasgow Veterinary School, Bearsden Road, Glasgow, Scotland

*Corresponding author; tel: +44 131 650 6228; fax:  + 44 131 7348; e-mail: sue.welburn@ed.ac.uk

Accepted 12 November 2002

Reliable DNA based methodologies to determine prevalence of trypanosome species in domestic livestock have been available for over 10 years.  Despite this, they are rarely used to generate baseline data for control operations for these diseases in the field.  Rather, such operations tend to rely on data which can be generated using low technology methods such as direct observation of parasites by light microscopy.  Here we show the pitfalls of relying on such low tech methodology which, although simple in its application, can provide inaccurate and inadequate data on which to base control methodologies. Our analysis of 61 cattle selected for trypanosome carrier status by either microscopy, low PCV or poor condition score, showed that 90% were infected with trypanosomes while 84% of the total were infected with T. brucei. Diagnosis by PCR on buffy coat preparations on Whatman^® FTA^® matrices was the most sensitive methodology relative to the gold standard, whereas microscopy was the least sensitive.  

Keywords: sleeping sickness, human African trypanosomiasis, epidemiology, chemotherapy, PCR.