Helminth Infection and Hemoglobin Status in Lao Schoolchildren

Background: Soil-transmitted helminth (STH) infections pose a considerable disease burden to children in developing countries. Although many communities treat children through school-based deworming programs, little is known about the ongoing burden of STH in remote areas and its relationship to nutritional outcomes such as iron status. In Lao PDR, no national or regional prevalence studies of STH have been carried out since 2000-2002, prior to the widespread deworming campaign. Objective: To estimate the prevalence of three common intestinal parasitic infection in Lao school children in a remote province. Data and methods: The study gathered stool samples and blood sampled (via finger stick) in a sample of 270 schools children ages 6-13. Stool samples were assessed using Kato-Katz thick smear technique. Blood samples were assessed using HemoCue photometers. Data were analyzed using bivariate and multivariate regression to determine prevalence of helminth infection and anemia, and the association of helminth infection and anemia with the age and sex of the child. Results: Prevalence of Ascaris lumbricoides was 24% (95% CI: 19-29%); of hookworm: 28% (95% CI: 22-33%); and of Trichuris trichiura, 28% (95% CI: 22-33%). Average number of infections per child was .79. More than half of children (56%) were infected with at least one helminth type. In addition, 14% of children were classified as anemic due to low hemoglobin, although iron status and helminth infection were not significantly associated. Conclusion: Helminth burden remains moderately high in this remote district of rural Laos. However, helminth burden does not appear to compromise children's iron status, at least in cross-section. Further research is needed to link the timing of deworming pill distribution with worm burden at different times of year.