Intestinal parasites among rural school children in southern Ethiopia: A cross-sectional multilevel and zero-inflated regression model
Authors: Hailu Hiwot , Lindtjørn Bernt 
Published: December 2019

Background

Over 28 million school-aged children are at risk of intestinal parasite infection in Ethiopia. Few studies have investigated household-level risk factors or applied multilevel analysis to account for the nested data structure. This study aimed to assess the prevalence, intensity, and risk factors of parasite infection among schoolchildren in rural South Ethiopia.

Methodology/Principal Findings

Using multistage random sampling, we recruited 864 students in the Wonago district. We applied multilevel-logistic and zero-inflated negative binomial regression models (ZINB). Risk factors were concentrated at the individual level; school-level and class-level variables explained less than 5% of the variance. The overall intestinal parasite prevalence was 56% (479/850);Trichuris trichiuraprevalence was 75.2% (360/479); andAscaris lumbricoidesprevalence was 33.2% (159/479). The rate of infection increased among children with anemia (AOR: 1.45 [95% CI: 1.04, 2.03]), wasting (AOR: 1.73 [95% CI: (1.04, 2.90]), mothers who had no formal education (AOR: 1.08 [95% CI: 1.25, 3.47]), and those in households using open containers for water storage (AOR: 2.06 [95% CI: 1.07, 3.99]). In the ZINB model,A. lumbricoidesinfection intensity increased with increasing age (AOR: 1.08 [95% CI: 1.01, 1.16]) and unclean fingernails (AOR: 1.47 [95% CI: 1.07, 2.03]). Handwashing with soap (AOR: 0.68 [95% CI: 0.48, 0.95]), de-worming treatment [AOR: 0.57 (95% CI: 0.33, 0.98)], and using water from protected sources [AOR: 0.46 (95% CI: 0.28, 0.77)] were found to be protective against parasitic infection.

Conclusions/Significance

After controlling for clustering effects at the school and class levels and accounting for excess zeros in fecal egg counts, we found an association between parasite infections and the following variables: age, wasting, anemia, unclean fingernails, handwashing, de-worming treatment, mother’s education, household water source, and water storage protection. Improving hygiene behavior, providing safe water at school and home, and strengthening de-worming programs is required to improve the health of schoolchildren in rural Gedeo.

Author summary

Intestinal parasite infections are common among school-aged children in Ethiopia. Several cross-sectional studies have investigated the prevalence and risk factors of these intestinal parasite infections. However, most were conducted in an urban setting in northern Ethiopia; they collected household-level risk factor information from the children, not the parents; and they restricted intestinal parasite infection data to binary outcomes. Therefore, we aimed to assess the prevalence and intensity of intestinal parasite infections and the related individual-, household-, and school-level risk factors among rural schoolchildren in southern Ethiopia. Using a multivariate, multilevel, regression model, we found minimal variation across class- and school-level factors for intestinal parasite infection prevalence. We found associations between intestinal parasite infections and most individual-level factors and some household-level factors. Therefore, interventions focusing on the individual, household, and school should be implemented to reduce the prevalence of infection and parasite load among schoolchildren.