Impact of the directly observed therapy (DOT) on the prevalence of soil-transmitted helminthiasis in low income children from Rio de Janeiro, Brazil

Between 2001 and 2008, the annual prevalence of soil-transmitted helminthiasis (STH) was investigated in children under five-years old from a public day care centre.  The faecal samples were examined by Kato-Katz and formalin-ether sedimentation (Ritchie) methods. Mebendazole 200mg daily for three days was recommended to Ascaris lumbricoides and/or Trichuris trichiura intestinal infection, the only relevant helminthiases were found. In 2003, 2005, 2006 and 2007, the treatment was performed in the institution where infected children have received directly observed therapy (DOT). In the others years, children have received it at home, after orientation of the parents. Information about symptoms was obtained before and after treatment. From 2001 to 2008, the coverage of exams was 79,4%, 74,9%, 68,1%, 53,9%, 65,7%, 51,7%, 61,2%, and 57%, from the 288 mean children annually enrolled. A significant statistical difference was demonstrated between the prevalence for helminthiasis infections in the first year (29,5%) and in the last year (12,3%). The helminthological positivity analyzed one year after the treatment was smaller in children that have received DOT in the institution than at home (p<0,05). Before treatment, the main complain was abdominal pain and anorexia. Mebendazole was given in a half dose for two Ascaris infected children that have weighed less than ten kilogram, including an eleven months old under nourishment child. After treatment, no intestinal disturbances were verified except Ascaris worm’s elimination in 45% of treated children. The re-examination showed negativity in all Ascaris infections and in 60% of Trichuris infections. One of Trichuris infected child went on infected after the fourth conventional re-treatment. Finally tricuriosis was cured after she has received Mebendazole 200mg daily for four days. We concluded that DOT was more effective in reducing helminthological infections in a studied institution.