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Genetic diversity of schistosomes and snails: implications for control

Published online by Cambridge University Press:  27 July 2009

DAVID ROLLINSON ,
JOANNE P. WEBSTER ,
BONNIE WEBSTER ,
SILVESTER NYAKAANA ,
ASLAK JØRGENSEN  and
J. RUSSELL STOTHARD
DAVID ROLLINSON*
Affiliation:
Wolfson Wellcome Biomedical Laboratories, Department of Zoology, Natural History Museum, Cromwell Road, LondonSW7 5BD, UK
JOANNE P. WEBSTER
Affiliation:
Department of Infectious Disease Epidemiology, Faculty of Medicine, Imperial College (St Mary's Campus), Norfolk Place, London, W2 1PG
BONNIE WEBSTER
Affiliation:
Wolfson Wellcome Biomedical Laboratories, Department of Zoology, Natural History Museum, Cromwell Road, LondonSW7 5BD, UK
SILVESTER NYAKAANA
Affiliation:
Makerere University, P.O. Box 7062, Kampala, Uganda
ASLAK JØRGENSEN
Affiliation:
DBL Parasitology, Health and Development, University of Copenhagen, Thorvaldsensvej 57, 1871 Frederiksburg C, Denmark
J. RUSSELL STOTHARD
Affiliation:
Wolfson Wellcome Biomedical Laboratories, Department of Zoology, Natural History Museum, Cromwell Road, LondonSW7 5BD, UK
*
*Corresponding author: David Rollinson, Wolfson Wellcome Biomedical Laboratories, Department of Zoology, Natural History Museum, Cromwell Road, LondonSW7 5BD, UK. Tel: +44 20 7942 518. Fax: +44 20 7942 5518. E-mail: d.rollinson@nhm.ac.uk
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Summary

Molecular approaches are providing new insights into the genetic diversity of schistosomes and their intermediate snail hosts. For instance, molecular tools based on the polymerase chain reaction are being developed for the diagnosis of schistosomiasis and the detection of prepatent schistosome infections in snails at transmission sites. Robust phylogenies of the different species of Schistosoma, Bulinus and Biomphalaria have been determined and novel methods are available to identify the different and cryptic taxa involved. Microsatellite analyses and mitochondrial DNA sequencing methods have been developed and are contributing to a better understanding of the genetic structure of both schistosome and snail populations. New sampling procedures to capture DNA of eggs and larval stages of schistosomes in field situations are facilitating more detailed and ethically advantageous studies on parasite heterogeneity. Knowledge of the genetic diversity of schistosome and snail populations adds a further dimension to the monitoring and surveillance of disease, and the implementation of new molecular-based approaches will be of increasing importance in helping to assess the impact of schistosomiasis control strategies.

Keywords

SchistosomessnailsMtDNAmicrosatellitesdiagnosispopulation geneticscontrolAfrica
Type
SECTION 4 MONITORING AND EVALUATION OF INTERVENTIONS
Information
Parasitology , Volume 136 , Special Issue 13: Control of schistosomiasis in sub-Saharan Africa , November 2009 , pp. 1801 - 1811
Copyright
Copyright © Cambridge University Press 2009

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