Epidemiology of intestinal helminth infections in a rural area of Antioquia, Colombia. Control by community treatment

Abstract

An epidemiological study on intestinal helminthic infections was done in a rural zone of Colombia, in 56 families with 347 persons older than 6 months. The main epidemiological findings were high fecal contamination of soil and water, deficient sanitation, poor personal hygiene and a very low socio-economic level. The prevalence rate for intestinal parasites in the sample examined, that involved 24% of the population, was 100%, 95% of which corresponded to pathogenic parasites. Anthelmintic treatment was administered twice at 6 months’ interval to the 347 persons, by using the combination pyrantel-oxantel at the single dose of 10 mg/kg of each drug. The postreatment parasitological examinations were performed to a sample similar to the initial sample in three occasions: 2 weeks and 6 months after the first treatment and 6 months after the second treatment, equivalent to 12 months after the initial treatment. The first study revealed 100% cure rate for ascariasis, 78% for trichuriasis and 53% for hookworm infections. In the last 2 infections the mean egg reductions in the cases not cured were 67% and 46% respectively. When we compared the prevalence rates in the initial study and after 6 and 12 months, we found that ascaris and trichuris were present in about one third of the population and that hookworms infected about one half of the population in the 6 month's study and only one fourth in the last control. For the 3 helminths an important decrease of the severe and moderate infections was observed, most cases showing light worm loads. These results show the benefits of the anthelmintic community based treatments in the long-term control of intestinal helmintic infections.