Fixed effects from the mixed-effects logistic regression for hookworm infection.

<p>This model used data from the 413 students between the ages of 5 and 18 years, and with complete data for the included variables. Of these 413 students, 71 (17%) were positive for hookworm. The variance (in the logit scale) of the random intercept for school in this model was 1.17.</p

Fixed effects from the mixed-effects logistic regression for with stunting.

<p>This model used data from the 3,686 students between the ages of 5 and 18 years, and with complete data for the included variables. Of these 3,686 students, 1,019 (28%) were stunted. The variance (in the logit scale) of the random intercept for school in this model was 1.16.</p

Fixed effects from the mixed-effects logistic regression for wasting.

<p>This model used data from the 3,686 students between the ages of 5 and 18 years, and with complete data for the included variables. Of these 3,686 students, 531 (14%) were stunted. The variance (in the logit scale) of the random intercept for school in this model was 0.381.</p

The school and woreda locations within SNNPR (A), and the position of SNNPR within Ethiopia (B).

<p>This figure was made using administrative boundaries from the GADM database of Global Administrative Areas [<a href="http://www.plosntds.org/article/info:doi/10.1371/journal.pntd.0005948#pntd.0005948.ref020" target="_blank">20</a>].</p

Sanitation, hookworm, anemia, stunting, and wasting in primary school children in southern Ethiopia: Baseline results from a study in 30 schools

<div><p>Background</p><p>Inadequate nutrition; neglected topical diseases; and insufficient water, sanitation, and hygiene (WASH) are interrelated problems in schools in low-income countries, but are not routinely tackled together. A recent three-year longitudinal study investigated integrated school health and nutrition approaches in 30 government primary schools in southern Ethiopia. Here, we report on baseline associations between sanitation, hookworm infection, anemia, stunting, and wasting.</p><p>Methods</p><p>In each school, the <i>Schistosoma mansoni</i>, <i>S</i>. <i>haematobium</i>, and soil-transmitted helminth infection intensities; blood hemoglobin concentrations; heights; and weights of approximately 125 students were assessed. Of these 125 students, approximately 20 were randomly selected for student WASH surveys. Of these 20, approximately 15 were randomly selected for household sanitation observations. School WASH was also assessed through a combination of observations and questions to the headteacher. Mixed-effects logistic regression was used to compare household sanitation with hookworm infection (the other parasites being much less prevalent); and hookworm infection with anemia, stunting, and wasting.</p><p>Findings</p><p>Blood, stool, and urine samples were provided by 3,729 children, and student WASH and household WASH surveys were conducted with 596 and 448 of these students, respectively.</p><p>Hookworm, <i>Ascaris lumbricoides</i>, <i>Trichuris trichiura</i>, and <i>S</i>. <i>mansoni</i> infections had prevalences of 18%, 4.8%, 0.6%, and 0.3%, respectively, and no <i>S</i>. <i>haematobium</i> infections were found. Anemia, stunting, and wasting had prevalences of 23%, 28%, and 14%, respectively.</p><p>No statistically significant associations were found between latrine absence or evidence of open defecation at home, and hookworm infection (adjusted odds ratio, OR = 1.28, 95% confidence interval, CI: 0.476–3.44; and adjusted OR = 1.21, 95% CI: 0.468–3.12; respectively); or between hookworm infection and anemia, stunting, or wasting (adjusted OR = 1.24, 95% CI: 0.988–1.57; adjusted OR = 0.992, 95% CI: 0.789–1.25; and adjusted OR = 0.969, 95% CI: 0.722–1.30; respectively).</p><p>Conclusions</p><p>In this setting, no statistically significant associations were found between sanitation and hookworm; or between hookworm and anemia, stunting, or wasting. More evidence on best practices for integrated school health interventions will be gathered from the follow-up surveys in this study.</p></div

The distributions of children’s anemia, stunting, and wasting classifications according to their hookworm infection intensities.

<p>Bar heights represent the percentages of each anemia, stunting, and wasting severity, in children with each hookworm infection intensity class. The number of children with each hookworm infection intensity-anemia/stunting/wasting class combination is given by <i>n</i>. Light, moderate, and heavy hookworm infections were defined as 1–1,999, 2,000–3,999, and 4,000 EPG or more, respectively [<a href="http://www.plosntds.org/article/info:doi/10.1371/journal.pntd.0005948#pntd.0005948.ref022" target="_blank">22</a>]. Mild stunting and wasting were defined as zHFA and zBMI values between -2 and -3, respectively, and severe stunting and wasting values below -3. Anemia classes were calculated using blood hemoglobin concentrations, taking into account age, gender, and elevation [<a href="http://www.plosntds.org/article/info:doi/10.1371/journal.pntd.0005948#pntd.0005948.ref023" target="_blank">23</a>].</p

Fixed effects from the mixed-effects logistic regression for anemia.

<p>This model used data from the 3,672 students between the ages of 5 and 18 years, and with complete data for the included variables. Of these 3,672 students, 850 (23%) were anemic. The variance (in the logit scale) of the random intercept for school in this model was 0.487.</p

School water scores and arithmetic mean intensities of <i>S</i>. <i>mansoni</i> infection.

<p>Kendall’s <i>τ</i>_<i>b</i> statistics, the equation of the least-squares line of best fit, and the number of included schools, are presented in the upper-right corner.</p

Flow diagram demonstrating the calculation of the sanitation score.

<p>Flow diagram demonstrating the calculation of the sanitation score.</p

School Water, Sanitation, and Hygiene, Soil-Transmitted Helminths, and Schistosomes: National Mapping in Ethiopia

<div><p>Background</p><p>It is thought that improving water, sanitation, and hygiene (WASH) might reduce the transmission of schistosomes and soil-transmitted helminths, owing to their life cycles. However, few large-scale studies have yet assessed the real extent of associations between WASH and these parasites.</p><p>Methodology/Principal Findings</p><p>In the 2013–2014 Ethiopian national mapping of infections with these parasites, school WASH was assessed alongside infection intensity in children, mostly between 10 and 15 years of age. Scores were constructed reflecting exposure to schistosomes arising from water collection for schools, from freshwater sources, and the adequacy of school sanitation and hygiene facilities. Kendall’s <i>τ</i>_<i>b</i> was used to test the WASH scores against the school-level arithmetic mean intensity of infection with each parasite, in schools with at least one child positive for the parasite in question.</p><p>WASH and parasitology data were available for 1,645 schools. More frequent collection of water for schools, from open freshwater sources was associated with statistically significantly higher <i>Schistosoma mansoni</i> infection intensity (Kendall’s <i>τ</i>_<i>b</i> = 0.097, 95% confidence interval, CI: 0.011 to 0.18), better sanitation was associated with significantly lower <i>Ascaris lumbricoides</i> intensity (Kendall’s <i>τ</i>_<i>b</i> = -0.067, 95% CI: -0.11 to -0.023) and borderline significant lower hookworm intensity (Kendall’s <i>τ</i>_<i>b</i> = -0.039, 95% CI: -0.090 to 0.012, <i>P</i> = 0.067), and better hygiene was associated with significantly lower hookworm intensity (Kendall’s <i>τ</i>_<i>b</i> = -0.076, 95% CI: -0.13 to -0.020). However, no significant differences were observed when comparing sanitation and infection with <i>S</i>. <i>mansoni</i> or <i>Trichuris trichiura</i>, or hygiene and infection with <i>A</i>. <i>lumbricoides</i> or <i>T</i>. <i>trichiura</i>.</p><p>Conclusions/Significance</p><p>Improving school WASH may reduce transmission of these parasites. However, different forms of WASH appear to have different effects on infection with the various parasites, with our analysis finding the strongest associations between water and <i>S</i>. <i>mansoni</i>, sanitation and <i>A</i>. <i>lumbricoides</i>, and hygiene and hookworm.</p></div