Use of a "tablet pole" for the administration of ivermectin for strongyloidiasis in a field study in Ecuador

Background:
Establishment of efficient control programs for strongyloidiasis, the infection by Strongyloides
stercoralis, is among the World Health Organization (WHO) targets for 2030. Ivermectin is a drug of
choice for strongyloidiasis, but its weight-based administration can be unfeasible in remote areas. We
evaluated a WHO tablet pole for administration of ivermectin in school-age children living in remote
villages in Ecuador.
Methods:
Children were enrolled in 16 villages in Esmeraldas Province of Ecuador, between July 2021 and June
2022. The pole identified four height intervals corresponding to ivermectin doses going from one to four
tablets. For each child, we calculated the dose (μg/kg) administered with both weight-based and polebased
administration. Results were classified as follows: optimal dose, acceptable, overdose, underdose.
Agreement between the two methods for estimating the number of tablets was assessed with Cohen’s
kappa coefficient. Estimations were reported with 95% confidence intervals (CIs).
Results:
Total of 778 children (47.3% female) were enrolled, with median age of 9.59 years (IQR: 7.42‒11.22).
Optimal dose was achieved for a higher proportion of children when assessed with weight (37.9%) than
with pole (25.7%). Underdose and overdose were more frequent with the pole (8.3% and 19.2%
children, respectively) than with the weight-based (3.7% and 6.0%, respectively) administration.
Agreement between weight-based and pole-based administration was moderate: 0.56 (95% CI 0.51,
0.61). The two methods indicated the same number of tablets in 71.6% (95% CI 0.684, 0.748) cases.
Conclusions:
In our setting, the tablet pole could be a valid alternative. The tool needs further evaluation in different
populations.