Halo Respirator Assessment of Reprocessing and Cleaning (ARC)
Stella E Hines, Sheldon Tai, Jennifer German, Hegang Chen, Maria Madden, Elizabeth Lulaj, Carmen Tong, Mihir Apte, Skylar Herman, Alex Birrell, Don Milton, Melissa A. McDiarmid
Background: Reusable respirators are an important alternative source of respiratory protection in healthcare to alleviate N95 supply shortages faced during surge demand. These respirators must be cleaned and disinfected after use to assure safety for reuse. Objective: This study aimed to evaluate whether use of conveniently available hospital chemical disinfectants alone removes influenza virus and facial contaminants similarly to use of a soap and water-based cleaning regimen along with disinfectant. Methods: CleanSpace® Halo reusable respirators were contaminated with simulated facial oils and influenza A virus via fine mist spray. Facial contamination was verified by use of fluorescent lotion. Half of the respirators were processed by cleaning in soap and water followed by wiping with a standard hospital chemical disinfectant; the other half were only wiped with chemical disinfectants. Disinfectants included: 70% isopropyl alcohol, 0.5% hydrogen peroxide, 0.55% quaternary ammonium compound and 0.1% bleach. Respirators were tested for influenza presence and viability following initial contamination, after wiping with disinfectant and then spraying with disinfectant. Results of quantitative RT-PCR to quantify influenza virus and TCID50 assays to titrate viral infectivity results were compared between the two processing strategies, among the four disinfectant types, and in comparison to the pre and post disinfectant spray step. The decrease in the presence of facial contaminants and disinfectant residue was expressed as percent reduction from baseline. Results: The lowest levels of influenza viral loads and the lowest levels of residual facial contaminants were observed on respirators undergoing cleaning with soap and water, disinfection with a chemical disinfectant, and with sleeve protection of the power unit. This was shown by both PCR and the TCID50 assays. Conclusion: The findings from this study provide an evidence base to design hospital cleaning and disinfection protocols for reusable Halo respirators. The most protective protocols should include cleaning with soap and water and disinfection of the respirators after use.