Soil-transmitted Helminth (STH) Infections in Northern Nigeria between 2000-2022: A Review

Soil-transmitted helminth (STH) infections, caused by parasitic nematodes, are significant public health concern in many parts of the world, including Nigeria. This review aims to comprehensively analyze the available studies and research trends on STH infections among children aged 0 – 17 years in northern Nigeria. The review focuses studies on the prevalence and risk factors related to STH infections from year 2000 – 2022 in this specific region and emphasizes the urgent need for effective control measure to mitigate the burden of these infections. The population involved 25 studies (92.6%) on School-aged Children (SAC) and 2 studies (7.4%) on Pre-school age Children (PSAC). A total of 8 514 children examined, 4 384 (51.5%) males and 4 130 (48.5%) females. Children from rural areas were 5 165 (60.7%) and 3 349 (39.3%) children from urban areas. Sample size ranges from 100 – 620, 22 (74.1%) studies employed Formol-ether concentration as stool examination technique, 4 (14.8%) and 3 (11.1%) used Kato-Katz and Direct smear methods respectively. The overall pool prevalence estimates (PPE) for STH infections were 3 160 (37.1%, 95% CI: 36.5–37.7). PPE for males 1 880 (59.5%, 95% CI: 58.6–60.1) was higher than for females 1 280 (40.5%, 95% CI: 54.2–55.3). Children from rural areas had the highest PPE 1 955 (37.9%) OR 1.26 (95% CI: 0.32–3.73) p=0.02, while children from urban areas had 3 160 (35.9%) OR 1.15 (95% CI: 0.62–5.02) p=0.01. There was no significant association between STH infections and community settings among SAC and PSAC. The most common PPEs by species identified was Ascaris lumbricoides 1 022 (32.3%, 95% CI: 31.7–32.9), hookworm 931 (29.5%, 95% CI: 28.9 – 30.1) and the least; Trichuris trichjura 356 (11.3%, 95% CI: 10.7 – 11.9). Children between 10 – 15 years had highest prevalence (48.6%), and 0 – 9 years had the least prevalence (23.5%) by age groups. Four common risk factors identified, walking barefooted 6 (22.2%) OR 1.16 (95% CI: 1.53 - 6.42) p-0.44, drinking untreated water 12 (44.4%) OR 1.66 (95% CI: 1.30 - 19.49) p=0.53, open field or bush defecation 8 (29.6) OR 3.41 (95% CI: 1.94 - 9.32) p=0.72 and eating unwashed fruits or vegetable 1 (3.7) OR 2.01 (95% CI: 1.32 - 4.51) p=0.54. The research underscores the need for enhanced surveillance, improved sanitation, and comprehensive sustainable interventions to reduce the prevalence and morbidity associated with STH infections in northern Nigeria.