Prevalence, Intensity, and Correlates of Schistosomiasis and Soil-Transmitted Helminth Infections after Five Rounds of Preventive Chemotherapy among School Children in Southern Ethiopia.

Tigist Dires Gebreyesus,Heran Gerba,Habtamu Gashaw,Birkneh Tilahun Tadesse,Tafesse Tadele,Eyasu Makonnen,Workagegnehu Degefe,Abbie Barry,Kalkidan Mekete,Eleni Aklillu,Parthasarathi Gurumurthy

doi:10.3390/pathogens9110920

Abstract

Preventive chemotherapy (PC) is a WHO-recommended strategy to control and eliminate schistosomiasis and soil-transmitted helminths (STHs). We assessed the prevalence, intensity, and correlates of schistosomiasis and STH infection after five rounds of PC in southern Ethiopia. A total of 3162 school children from four schools in Wondo Gennet and Hawella Tula districts were screened for Schistosoma mansoni and STHs infection. The overall prevalence of S. mansoni infection was 25.8% (range between schools 11.6% to 54.1%), with light (19.1%), moderate (5.3%), and heavy (1.4%) infection intensities. A total of 61.6% S. mansoni-infected children were STH co-infected. The overall prevalence of STHs infection was 54.7% (range between schools 30.6–71.0%), with moderate-to-heavy intensity infections being 16.3%. Ascaris lumbricoides was the most prevalent 45% (95% CI, 43.5–47) followed by Trichuris trichiura 25.3% (95% CI, 23.8–26.9) and hookworm 6.1% (95% CI, 5.3–7). A total of 33.7% of STHs-infected children had A. lumbricoides and T. trichiura co-infections. S. mansoni infection was significantly associated with school and STHs co-infection (p < 0.001). STH infection was correlated with school and younger age (p < 0.001). Despite repeated PC, S. mansoni and STH infection remain significant health problems, and the WHO target to control schistosomiasis and eliminate STH by 2020 may not be achieved. Intensified control and prevention measures, including drug efficacy surveillance, is recommended.

Highlights

Neglected tropical diseases (NTDs) such as schistosomiasis and soil-transmitted helminths (STHs, known as intestinal worms) remain major public health problems in many parts of the world [1]
Out of the total of 6184 students enrolled in the four primary schools in the two rural districts, 3162 school children participated in this study
Hawella Tula district is located along the shore of Lake Hawassa, and Wondo Gennet district is known for its hot water spring

Summary

Introduction

Neglected tropical diseases (NTDs) such as schistosomiasis ( known as bilharziasis) and soil-transmitted helminths (STHs, known as intestinal worms) remain major public health problems in many parts of the world [1]. About 252 million people were estimated to be infected with schistosomiasis in 2015 [3], and from these, the sub-Saharan region constitutes more than 90% of the disease burden [2]. STHs are the most widespread neglected tropical disease; worldwide more than 1.5 billion people are infected with Ascaris lumbricoides, Trichuris trichiura (whipworms), and/or hookworm in over 100 endemic countries, together accounting for a major burden of parasitic disease worldwide [4]. About 37.3 million people are currently living in areas where schistosomiasis is endemic in Ethiopia [5]. Ethiopia is listed among the top five sub-Saharan countries with the highest prevalence of STHs—second, third, and fourth highest for ascariasis, hookworm infection, and trichiurasis, respectively [6]. All age groups can have schistosomiasis and STHs infections, most infections occur in pre-school and school-aged children

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Discussion

Conclusion