Germicidal ultraviolet (GUV) light appliances in long-term care facilities for older adults did not significantly reduce acute respiratory infection rates within study cycles but did show a significant reduction in weekly infections rate over time.

According to the study authors, "...this trial demonstrated the effectiveness of an adjunct infection control strategy to address airborne pathogen transmission in a healthcare setting."

"For the present, clearer data are needed to justify the expense and complexity of adding air cleaning technologies to clinical spaces that already meet contemporary ventilation standards for healthcare," the author of a linked commentary wrote.

This study was led by Andrew P. Shoubridge, PhD , South Australian Health and Medical Research Institute, Adelaide, Australia. It was published online on July 28, 2025, in JAMA Internal Medicine.

The COVID-19 pandemic and continuously changing public health measures limited data for power calculations, restricted data collection, and strained diagnostic services reducing confirmation. Unrestricted movement of residents and staff between intervention and control zones could have affected pathogen transmission patterns.

This study received support from a Medical Research Future Fund grant from the Australian Government. Several authors reported receiving grants from various organizations and pharmaceutical companies.