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Morphometric variability of Schistosoma intercalatum eggs: a diagnostic dilemma

Published online by Cambridge University Press:  05 June 2009

J. Almeda*
Affiliation:
Unidad de Epidemiologia y Bioestadistica, Hospital Clinic, Universidad de Barcelona, Spain
C. Ascaso
Affiliation:
Unidad de Epidemiologia y Bioestadistica, Hospital Clinic, Universidad de Barcelona, Spain
G. A. Marçal
Affiliation:
Laboratorio Central, Hospital Ayres Menezes, Ministerio da Saude, Republica de São Tomé and Principe
M. Corachan
Affiliation:
Seccion de Medicina Tropical, Hospital Clinic, Universidad de Barcelona, Spain
V. R. Southgate
Affiliation:
Department of Zoology, The Natural History Museum, Cromwell Road, London, SW7 5BD, UK
D. Rollinson
Affiliation:
Department of Zoology, The Natural History Museum, Cromwell Road, London, SW7 5BD, UK
*
*Unidad de Epidemiologia y Bioestadistica, Fundacio Clinic per a la Recerca Biomedica, Villarroel 170, 08036 Barcelona, Spain.

Abstract

Variability of Schistosoma intercalatum eggs in shape and size, and their similarity to those of S. haematobium presented a problem of species identification when egg morphology was the diagnostic criterion used in a study of human schistosomiasis conducted on São Tomé and Principe. More than 2500 egg measurements were obtained by light micoscopy to gather data relating to size variability of S. intercalatum eggs, to evaluate whether factors such as age of host, sex of host and intensity of infection are correlated with variability, and the data were compared with previously published measurements on different isolates and strains of S. intercalatum: the range in length (104–203 μm) embraces most of the measurements reported in other studies of S. intercalatum eggs. There was no correlation either between age and sex of the host, or intensity of infection with variability of egg size. Comparison between measurements of the eggs of S. haematobium, S. intercalatum and S. bovis eggs are presented.

Type
Research Papers
Copyright
Copyright © Cambridge University Press 1996

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