Risk of soil-transmitted helminthiasis among agrarian communities of Kogi State, Nigeria: Evaluated in the context of The Soil-Transmitted Helminthiasis Advisory Committee recommendation 2016
Authors: Anunobi Joy T. , Okoye Ikem C. , Aguzie Ifeanyi Oscar N. , Ndukwe Yvonne E. , Okpasuo Onyekachi J. 
Published: June 2019

Soil-transmitted helminths (STH) have remained a major threat to human especially children in developing countries including Nigeria. Interventions have always been geared towards school-aged children, neglecting preschool-aged children and occupational risk adults. The Soil-Transmitted Helminthiasis Advisory Committee (STHAC) recently suggested incorporating other at-risk groups. In the context of this recommendation, this study assessed the associated risk of STH infection among agrarian communities of Kogi State, Nigeria. A total of 310 individuals of all ages participated in the cross-sectional survey. Stool samples were analyzed using standard Kato-Katz method. A total of 106 (34.2%) individuals were infected with at least one STH. Hookworm was the most prevalent (18.1%); followed byAscaris lumbricoides(16.8%). Worm intensity was generally light. Prevalence of infection was similar between four age groups considered (preschool, school, ‘women of reproductive age’ and older at-risk group). Poor socio-economic status (SES) was a major risk for STH infection. Using a 20-assets based criteria, 68 (23.1%) and 73 (24.7%) of 295 questionnaire respondents were classified into first (poorest) and fifth (richest) wealth quintiles respectively. Risk of infection with STH was 60% significantly lower in the richest wealth quintile compared to the poorest (Prevalence Ratio (PR) = 0.4843, 95% CI = 0.2704 – 0.8678, p = 0.015). Open defecators were more likely to harbour STH than those who did not (PR = 1.7878, 95% CI = 1.2366 – 2.5846, p = 0.00201). Pit latrine and water closet toilet each approximately reduced STH infection by 50% (p < 0.05). Preventive chemotherapy for all age groups, health education and provision of basic amenities especially toilets are needed in order to achieve the goal toward the 2020 target of STH control.

Author summary

Soil-transmitted helminths (STHs) are major cause of morbidities globally, especially among children in developing countries such as Nigeria. Present World Health Organization recommended control strategy solely require preventive chemotherapy targeting preschool-aged children (PSAC) and school-aged children (SAC), and the recently included women of reproductive age (WRA). The Soil-Transmitted Helminthiasis Advisory Committee (STHAC) which is saddled with responsibility of evaluating STHs status and providing appropriate recommendations proposed that preventive chemotherapy be extended to other at-risk groups. This study evaluates this and some other recommendations of STHAC 2016 using sections of a state in Nigeria where soil-transmitted helminthiasis is endemic.

Findings from this study supports recommendations for extension of preventive chemotherapy to other at-risk groups apart from PSAC and SAC. It supports WASH (water, sanitation and hygiene) as integral part of STH control. This finding emphasizes the need for health education and change in attitude which could promote tenets of WASH. And very importantly, the study emphasizes the role of poverty in the persistence of STH transmission. It is the belief of the authors that there is the need for improved socio-economic status for sustainable gains of control efforts.