Analysis of Range and Use of a Hybrid Hydrogen Peroxide System for Biosafety Level 3 and Animal Biosafety Level 3 Agriculture Laboratory Decontamination.

Introduction: The applications of fumigation and the challenges that high-containment facilities face in achieving effective large volume decontamination are well understood. The Biosecurity Research Institute at Kansas State University sought to evaluate a novel system within their biosafety level 3 (BSL-3) and animal biosafety level 3 agriculture (ABSL-3Ag) facility. Methods: The system chosen for this study is the CURIS® Hybrid Hydrogen PeroxideTM (HHPTM) system, comprising a mobile 36-pound (16 kg) device delivering a proprietary 7% hydrogen peroxide (H2O2) solution. To examine the system's efficacy in multiple laboratory settings, two BSL-3 laboratories (2,281 [65 m3] and 4,668 ft3 [132 m3]) with dropped ceiling interstitial spaces and an ABSL-3Ag necropsy suite (44,212 ft3 [1,252 m3]) with 21-foot (6.4 m) ceilings were selected. Biological indicators (BIs) of Geobacillus stearothermophilus (1.7 × 106 organisms) on steel spore carriers and H2O2 chemical indicators (CIs) were used to provide validation. Results: After cycle optimization, the smaller laboratory had a total of 60 BIs over two treatments that demonstrated a greater than 6-log reduction of bacterial spores. The larger laboratory (192 BIs) and the necropsy suite (206 BIs) had no BIs positive for spore growth when incubated at 60°C for 24 h per manufacturer's specifications. Conclusion: Overall successful results through multiple components of this study demonstrate that the HHP device, paired with the pulsed 7% H2O2 solution, achieved efficacy regardless of variables in laboratory size and layout. Perceived challenges such as 21-ft (6.4 m) ceiling heights, active equipment, and difficult to access ceiling interstitial spaces proved unfounded. Given the successful sterilization of all challenged BIs, the HHP system presents a useful alternative for high level decontamination within BSL-3 and ABSL-3Ag facilities.

Decontamination of respirators amid shortages due to SARS-CoV-2.

The pandemic created by SARS-CoV-2 has caused a shortage in the supplies of N95 filtering facepiece respirators (FFRs), disposable respirators with at least 95% efficiency to remove non-oily airborne particles, due to increasing cases all over the world. The current article reviewed various possible decontamination methods for FFR reuse including ultraviolet germicidal irradiation (UVGI), hydrogen peroxide vapor (HPV), microwave-generated steam (MGS), hydrogen peroxide gas plasma (HPGP), and 70% or higher ethanol solution. HPV decontamination was effective against bacterial spores (6 log10 reduction of Geobacillus stearothermophilus spores) on FFRs and viruses (> 4 log10 reduction of various types of viruses) on inanimate surfaces, and no degradation of respirator materials and fit has been reported. 70% or higher ethanol decontamination showed high efficacy in inactivation of coronaviruses on inanimate surfaces (> 3.9 log10 reduction) but it was lower on FFRs which filtration efficiency was also decreased. UVGI method had good biocidal efficacy on FFRs (> 3 log10 reduction of H1N1 virus) combined with inexpensive, readily available equipment; however, it was more time-consuming to ensure sufficient reduction in SARS-CoV-2. MGS treatment also provided good viral decontamination on FFRs (> 4 log10 reduction of H1N1 virus) along with less time-intensive process and readily available equipment while inconsistent disinfection on the treated surfaces and deterioration of nose cushion of FFRs were observed. HPGP was a good virucidal system (> 6 log10 reduction of Vesicular stomatitis virus) but filtration efficiency after decontamination was inconsistent. Overall, HPV appeared to be one of the most promising methods based on the high biocidal efficacy on FFRs, preservation of respirator performance after multiple cycles, and no residual chemical toxicity. Nonetheless, equipment cost and time of the HPV process and a suitable operating room need to be considered.

Vapourized hydrogen peroxide decontamination in a hospital setting inactivates SARS-CoV-2 and HCoV-229E without compromising filtration efficiency of unexpired N95 respirators.

BACKGROUND: The COVID-19 pandemic highlighted the need for evidence-based approaches to decontamination and reuse of N95 filtering facepiece respirators (FFRs). We sought to determine whether vapourized hydrogen peroxide (VHP) reduced SARS-CoV-2 bioburden on FFRs without compromising filtration efficiency. We also investigated coronavirus HCoV-229E as a surrogate for decontamination validation testing. METHODS: N95 FFRs were laced with SARS-CoV-2 or HCoV-229E and treated with VHP in a hospital reprocessing facility. After sterilization, viral burden was determined using viral outgrowth in a titration assay, and filtration efficiency of FFRs was tested against ATSM F2299 and NIOSH TEB-STP-APR-0059. RESULTS: Viable SARS-CoV-2 virus was not detected after VHP treatment. One replicate of the HCoV-229E laced FFRs yielded virus after processing. Unexpired N95 FFRs retained full filtration efficiency after VHP processing. Expired FFRs failed to meet design-specified filtration efficiency and therefore are unsuitable for reprocessing. DISCUSSION: In-hospital VHP is an effective decontaminant for SARS-CoV-2 on FFRs. Further, filtration efficiency of unexpired respirators is not affected by this decontamination process. CONCLUSIONS: VHP is effective in inactivating SARS-CoV-2 on FFRs without compromising filtration efficiency. HCoV-229E is a suitable surrogate for SARS-CoV-2 for disinfection studies.

COVID-19 global pandemic planning: Decontamination and reuse processes for N95 respirators.

IMPACT STATEMENT: There is a critical shortage of personal protective equipment (PPE) around the globe. This article describes the safe collection, storage, and decontamination of N95 respirators using hydrogen peroxide vapor (HPV). This article is unique because it describes the HPV process in an operating room, and is therefore, a deployable method for many healthcare settings. Results presented here offer creative solutions to the current PPE shortage.