Ivermectin-Based Mass Drug Administration for Scabies in Northern India: A Single-Arm Community Intervention Trial.

BACKGROUND

Scabies and impetigo cause direct health effects and contribute to severe infectious and immune-mediated complications. Ivermectin-based mass drug administration can reduce scabies and impetigo prevalence in island settings with high prevalence, but the effectiveness in moderate-prevalence settings is not known.

METHODS

We conducted a single-arm, before-after community intervention trial. Mass drug administration was offered to the entire population of 4 villages in Uttarakhand, India. The treatment consisted of 2 doses, given 7 days apart, of oral ivermectin (∼200 μg/kg), or topical 5% permethrin if ivermectin was contraindicated. The primary outcome was the prevalence of scabies at 12 months compared with baseline, as diagnosed using clinical assessment and the 2020 International Alliance for the Control of Scabies criteria. Secondary outcomes included the prevalence of impetigo at each time point. The trial was registered with the Australian and New Zealand Trials Registry (ACTRN12619001712190).

RESULTS

In January 2020, 1211 participants were enrolled (100% of the estimated village population). Treatment coverage was high-1204 (99.4%) and 1177 (97.2%) received 1 and 2 doses, respectively. Scabies was diagnosed in 91 participants (7.5%) and impetigo in 15 (1.2%). In February 2021, 1190 (98.3% of baseline) participants re-enrolled, and of these 11 had scabies (0.9%; relative risk reduction, 87.7%; 95% CI, 77.1%-93.4%) and 5 had impetigo (0.4%; relative risk reduction, 66.1%; 95% CI, 7.0%-87.6%).

CONCLUSIONS

A single round of ivermectin-based mass drug administration substantially reduced the prevalence of scabies and impetigo in this setting with moderate scabies prevalence in northern India.