Parasitology

SECTION 5 TOWARDS FUTURE USE OF PRAZIQUANTEL

Schistosomiasis and neglected tropical diseases: towards integrated and sustainable control and a word of caution

J. UTZINGERa1 c1, G. RASOa2a3a4, S. BROOKERa5a6, D. DE SAVIGNYa1, M. TANNERa1, N. ØRNBJERGa7, B. H. SINGERa8 and E. K. N'GORANa4a9

a1 Department of Public Health and Epidemiology, Swiss Tropical Institute, P.O. Box, CH–4002 Basel, Switzerland

a2 Division of Epidemiology and Social Medicine, School of Population Health, The University of Queensland, Public Health Building, Herston Road, Brisbane, Queensland 4006, Australia

a3 Molecular Parasitology Laboratory, Queensland Institute of Medical Research, 300 Herston Road, Brisbane, Queensland 4006, Australia

a4 Centre Suisse de Recherches Scientifiques, 01 BP 1303, Abidjan 01, Côte d'Ivoire

a5 Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London WC1E 7HT, United Kingdom

a6 Malaria Public Health and Epidemiology Group, KEMRI/Wellcome Trust Research Programme, P.O. Box 43640–00100, Nairobi, Kenya

a7 DBL – Centre for Health Research and Development, Faculty of Life Sciences, University of Copenhagen, Thorvaldsensvej 57, DK-1871 Frederiksberg C, Denmark

a8 Office of Population Research, Princeton University, Princeton, NJ 08544, USA

a9 UFR Biosciences, Université d'Abidjan-Cocody, 22 BP 582, Abidjan 22, Côte d'Ivoire

SUMMARY

In May 2001, the World Health Assembly (WHA) passed a resolution which urged member states to attain, by 2010, a minimum target of regularly administering anthelminthic drugs to at least 75% and up to 100% of all school-aged children at risk of morbidity. The refined global strategy for the prevention and control of schistosomiasis and soil-transmitted helminthiasis was issued in the following year and large-scale administration of anthelminthic drugs endorsed as the central feature. This strategy has subsequently been termed ‘preventive chemotherapy’. Clearly, the 2001 WHA resolution led the way for concurrently controlling multiple neglected tropical diseases. In this paper, we recall the schistosomiasis situation in Africa in mid-2003. Adhering to strategic guidelines issued by the World Health Organization, we estimate the projected annual treatment needs with praziquantel among the school-aged population and critically discuss these estimates. The important role of geospatial tools for disease risk mapping, surveillance and predictions for resource allocation is emphasised. We clarify that schistosomiasis is only one of many neglected tropical diseases and that considerable uncertainties remain regarding global burden estimates. We examine new control initiatives targeting schistosomiasis and other tropical diseases that are often neglected. The prospect and challenges of integrated control are discussed and the need for combining biomedical, educational and engineering strategies and geospatial tools for sustainable disease control are highlighted. We conclude that, for achieving integrated and sustainable control of neglected tropical diseases, a set of interventions must be tailored to a given endemic setting and fine-tuned over time in response to the changing nature and impact of control. Consequently, besides the environment, the prevailing demographic, health and social systems contexts need to be considered.

(Received August 22 2009)

(Revised October 10 2009)

(Accepted October 10 2009)

Correspondence:

c1 Corresponding author: Jürg Utzinger, Department of Public Health and Epidemiology, Swiss Tropical Institute, P.O. Box, CH–4002 Basel, Switzerland. Tel.: +41 61 284-8129; Fax: +41 61 284-8105; E-mail: juerg.utzinger@unibas.ch

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