Abstract / Summary
Abstract Conventional hand sanitizers provide immediate but short-lived bactericidal and virucidal effects, necessitating their frequent use to reduce contact transmission. This double-blind, parallel-group, cluster-randomized controlled trial evaluated the effect of repeated use of the study formulation. Healthy employees and their cohabiting family members (clusters) were assigned to use either the study formulation or a commercially available 79.7% ethanol-based sanitizer 5–10 times daily for 72 days (December 2023–February 2024). The primary outcome was the cumulative incidence of upper respiratory symptoms, defined as fever ≥ 37.8 °C with cough, sore throat, and/or nasal discharge. Among the 568 participants (study-formulation group, 285; ethanol-based sanitizer group, 283) across 417 clusters, upper respiratory symptoms occurred in 35 and 58 participants, respectively. The study-formulation group showed significantly lower risk (hazard ratio [HR]: 0.58; 95% confidence interval [CI]: 0.37–0.89, P = 0.013; approximately 40% lower cumulative incidence), with fewer illness-related work restrictions. Adverse events were infrequent and unrelated to the study interventions. Repeated use of the study formulation was well tolerated and associated with fewer upper respiratory symptoms and work restrictions than ethanol-based sanitizers.