Evaluation of a hand hygiene intervention in two primary schools using UV-based feedback and AI-assisted image analysis.

OBJECTIVES

Hand hygiene prevents infectious diseases in schoolchildren, but objective assessment of technique remains largely unexplored in school settings. The aim of the present study is to evaluate a school-based intervention on hand hygiene in primary schools.

STUDY

DESIGN

We conducted a controlled school-based community intervention study with school-level allocation, using a before-after repeated-measures design in two primary schools in Tarragona, Spain.

METHODS

A total of 126 children aged 8-12 years participated (64 intervention, 62 control). The intervention combined a 30-min session on the 7-step alcohol-based hand rub technique with feedback using fluorescent hand rub and a custom UV device. Hand hygiene quality was measured at baseline and at 1, 3, and 6 months as the proportion of total hand surface area adequately covered, including the palmar and dorsal surfaces of both hands. Images were analysed using an artificial intelligence-assisted tool to support more standardised outcome assessmentLongitudinal effects were analysed exploratorily with a beta mixed-effects regression model.

RESULTS

Adjusted hand coverage was similar between groups at baseline. At 1 month, both schools showed increased adjusted coverage. From 3 months onwards, trajectories diverged. The intervention school showed higher adjusted coverage than the control school at 3 months (adjusted mean difference 0.031; 95% CI: 0.010-0.052) and 6 months (0.041; 95% CI: 0.021-0.061).

CONCLUSIONS

This exploratory study suggests that combining structured hand hygiene education with immediate UV visual feedback may contribute to sustained improvements in hand hygiene technique in primary school settings. The AI-assisted image-analysis workflow supported partial standardisation of outcome assessment, although the fluorescence-detection step required human supervision.