Evaluating the efficacy of the praziquantel dose pole for schistosomiasis treatment: A multi-country systematic review

Schistosomiasis is a neglected tropical disease targeted for elimination as a public health problem by 2030 under the WHO’s roadmap. Praziquantel, administered via the dose pole, which estimates the number of tablets needed for treatment according to an individual’s height, has been used as preventive chemotherapy (PC) for 25 years, particularly for school-aged children (SAC). In 2022, PC was required for schistosomiasis in 50 countries, affecting a total of 264.3 million people, including 129.4 million adults. This systematic review evaluates the accuracy of the praziquantel dose pole across 64,212 individuals from 21 countries, focusing on its efficacy in delivering optimal, acceptable, insufficient, and excessive doses during school-based and community-wide treatment campaigns for schistosomiasis. The search strategy included the terms “dose pole” OR “tablet pole” AND “praziquantel” AND “schistosomiasis” in four databases (PubMed, Scopus, LILACS, and Embase), ranging from 1999 to September 2024. The dose pole demonstrated 96% accuracy in providing optimal/acceptable doses (30–60mg/Kg) to SAC. However, its effectiveness markedly declined for adults (15–95 years), with a pooled proportion of 19% receiving insufficient doses (<30mg/Kg), ranging from 10% to 34%. These discrepancies arise from misalignments between adult body metrics and the dose pole’s height-based dosing, primarily due to overweight and obesity, leading to underdosing. While the dose pole remains effective for SAC, its limitations for adults necessitate urgent adaptation or alternative dosing strategies to ensure equitable and effective treatment across all age groups.