<p>Impact of annual preventive mass chemotherapy for soil-transmitted helminths among primary school children in an endemic area of Gurage zone: a prospective cross-sectional study</p>

Abstract

Background and aim School-based preventive mass chemotherapy has been a key component of Ethiopia's national plan for the control of soil-transmitted helminths. Without an impact evaluation on the impact of a deworming program on infection levels, it is unclear whether the deworming program warrants levels of environmental transmission of infection. This study aimed to determine the impact of annual preventive mass chemotherapy for soil-transmitted helminths among schoolchildren in an endemic area of Gurage zone, south-central Ethiopia. Methods A repeated school-based quantitative prospective cross-sectional method was employed. Data were collected from study participants selected using systematic sampling with probability proportional to size at baseline and after annual treatment. Fresh stool samples were collected and processed using the Kato─Katz technique at the Wolkite University parasitology laboratory. SPSS-21 was used for data management and analysis. Changes in parasitological variables after treatment were estimated. Results Overall, 41.1% prevalence and 22.3% mean geometric infection-intensity reduction were found. Reductions in prevalence of Schistosoma mansoni and hookworms were 13.2% and 15.3%, respectively. Similarly, decreases in prevalence were seen in Ascaris lumbricoides and Trichuris trichiura , representing 94.4% and 80.0% reduction rates, respectively, while 25.9% of the children had heavy S. mansoni (≥400 eggs per gram) infections at baseline, which were reduced to 4.5% after annual treatment. Geometric mean infection intensity–reduction rates for hookworms, A. lumbricoides , and T. trichiura were 80.8%, 20.2%, and 96.7%, respectively. Conclusion Annual mass chemotherapy failed to clear soil-transmitted helminths completely in the present study. However, it resulted in a substantial reduction in overall prevalence and infection intensity. Therefore, other than deworming for school children, interventions such as access to improved personal hygiene and environmental hygiene in school should be emphasized to interrupt transmission.

Prevalence and intensity of soil-transmitted helminth infections and associated risk factors among household heads living in the peri-urban areas of Jimma town, Oromia, Ethiopia: A community-based cross-sectional study

“…The result of this study illustrates the importance of addressing the community-based reservoir to reduce the reinfections of the treated children and other at-risk populations through expanding the target population, integrated with health and hygiene education and the provision of adequate sanitation facilities [ 31 , 32 , 34 ]. A study conducted among agrarian communities of Kogi State, Nigeria recommends the inclusion of all age groups in preventive chemotherapy along with health education and provision of basic sanitation facilities to eliminate STH and break their transmission by 2025 [ 36 , 37 ].…”

“…This implies that if the infected adult populations of the community are left untreated, they may serve as an important reservoir and source of re-infection for the treated children, contributing to the sustained transmission of the STH in the community. Previous studies conducted in various countries have shown that STH reinfections occur rapidly after treatment, particularly for A. lumbricoides and T. trichiura, and hence have a significant impact on the success of preventive mass chemotherapy [31][32][33][34][35].…”

Evaluation of School-Based Health Education Intervention on the Incidence of Soil-Transmitted Helminths in Pupils of Rural Communities of Eastern Kogi State, North Central Nigeria

“…Series of studies have reported the effectiveness of chemotherapy in control of STH infection especially when done annually. A study in Gurage Zone, Ethiopia [ 39 ], reported that chemotherapy results in substantial reduction in overall prevalence and intensity of STHs. The residual infections with STHs in this study are a reflection of the maintenance of transmission among the untreated populations in the community which are constantly in contact with the dewormed children.…”

Impact of School-Based Health Education Intervention on the Incidence of Soil-transmitted Helminths in Pupils of Rural Schools, Kogi East, North Central Nigeria.

“…Series of studies have reported the effectiveness of chemotherapy in control STHs infection especially when done annually. A study in Gurage Zone, Ethiopia [31] reported that chemotherapy results in substantial reduction in overall prevalence and infection intensity of STHs. The residual infections with STHs in this study is a re ection of the maintenance of transmission among the untreated populations in the community which are constantly in contact with the dewormed children.…”