Volume 34, Issue 2
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645



Statistical methods analyzing changes in dispersion patterns of parasites among hosts were applied to egg excretion data from a five-year study of a cohort of 1,400 boys in 3 villages in Upper Egypt. Despite significant changes in mean density of the parasites in the first 4 years, the degree of aggregation of among the cohort did not change markedly in analysis of egg count data obtained semiannually. Two other related measures of dispersion, mean crowding and patchiness, were also obtained and compared to prevalence and mean intensity, the components determining mean density of schistosomes among hosts. Anti-schistosomal chemotherapy with metrifonate in the cohort did not succeed in appreciably reducing the mean density of over a one-year follow-up. The dispersion pattern of among the study group was not markedly altered. Prevalence and mean intensity were useful indicators of changes in the degree of aggregation of among hosts. The inability of chemotherapy to provide a persistent decline in the mean density parameter is reflected in the rise of mean intensity and prevalence of 1 year post-therapy. It is suggested that analysis of quantifiable changes in dispersion patterns of among their hosts can be a useful aid in planning and assessment of control strategies.


Article metrics loading...

The graphs shown below represent data from March 2017
Loading full text...

Full text loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error