Protozoan infections and intestinal helminthiasis among the population of a village in the northern Sudan savannah area of Mali (West Africa).

A cross sectional survey was carried out on intestinal parasites in a rural village located in a Sudan savannah area of Mali in September 1994. This survey was aimed to describe the prevalence of intestinal protozoa and helminths, and to evaluate the possible epidemiological impact of some sociobehavioural factors. A total of 209 stool specimens were examined with 3 methods: fresh stool examination, Kato thick smear technique and a formalin-ether concentration technique in a closed system. Cryptosporidium was also searched following the Ziehl-Neelsen staining and the immunofluorescence method using monoclonal antibody. Microsporidia were investigated by Trichrome staining technique. The concentration technique, as expected, was the more sensitive method: the protozoan cyst rate and the helminth egg rate were 70.3% and 11%, respectively. The low prevalence of intestinal nematodes, unexpected for this area, could be attributed to the improvement in sanitation (traditional WC present in 73.9% of the families), but also to the repeated treatments of the population against onchocercosis with ivermectin since 1992. We found no cases of isosporosis, cryptosporidiosis and microsporidiosis in our study population, neither significant association between socio-behavioural factors and parasitic infections.