Prevalence of selected intestinal nematodes in a suburban area in Matara district, and the effect of Albendazole on them

Abstract

Intestinal helminth infections carry the heaviest burden of morbidity to the children as well as adults in the world and also in Sri Lanka. The objective of this study was to investigate the prevalence of three selected geo-helminths namely, the whipworm Trichuris irichiura (Linnaeus, 1771), the hookworm Necalor americanus (Stiles, 1902) and the round worm Ascaris lumbricoides (Linnaeus, 1758), and the effect of Albendazole on them in an urban slum community called Hamugewatta, Walgama in Matara district. Stool samples that were collected from a total of 143 residents in the community in February 2003, and other set of samples previously collected from the same group of residents six months earlier in 2002 were utilized to examine the initial prevalence of the three helminthes. Keto-Katz thick smear method was used to observe helminth eggs in faeces and the density in eggs per gram weight of faecal matter was estimated. The sampling population was treated with a single dose of 400 mg Albendazole, and the stool samples collected two weeks later were examined for parasitic eggs. From 2002 samples, the prevalence of T. Irichiura, N. americanus and A. lumbricoides were 84%, 22% and 10% respectively, and there was an apparently discernible decrease in prevalence of the nematodes in the samples collected six months later with a significant egg reduction rate. In the samples collected in 2003 prior to Albendazole treatment, the three helminthes were prevalent with 95%, 5% and 5% respectively while 55%, 100% and 100% respective cure rates were achieved after the Albendazole treatment. In other words the post treatment samples were positive only for Linnaeus, 1758), and the T. trichiuru with a prevalence of 57% and an accompanied egg reduction rate of 20%. An apparently decreasing trend in the prevalence of these infections within the selected population could be inferred when considering the relevant statistics from 1996 towards 2003. However, a persistent T. trichiura infection in a mild state seems to occur even after treatment with Albendazole. The effect of the drug Albendazole should be further investigated using a large population, as the population size treated in the present study was relatively small and the pre-treated prevalence of N. americanus and A. lumbricoicles were considerably low.