Viral Special Pathogens Branch, Division of High Consequence Pathogens and Pathology, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
Global Health Department, Milken Institute School of Public Health, The George Washington University, Washington, DC, USA.
Am J Infect Control. 2022 Aug;50(8):863-870. doi: 10.1016/j.ajic.2022.02.016.
The COVID-19 pandemic resulted in a worldwide shortage of N95 respirators, prompting the development of decontamination methods to enable limited reuse. Countries lacking reliable supply chains would also benefit from the ability to safely reuse PPE. Methylene blue (MB) is a light-activated dye with demonstrated antimicrobial activity used to sterilize blood plasma. Decontamination of respirators using photoactivated MB requires no specialized equipment, making it attractive for use in the field during outbreaks.
We examined decontamination of N95 and KN95 respirators using photoactivated MB and 3 variants of SARS-CoV-2, the virus that causes COVID-19; and 4 World Health Organization priority pathogens: Ebola virus, Middle East respiratory syndrome coronavirus, Nipah virus, and Lassa virus. Virus inactivation by pretreating respirator material was also tested.
Photoactivated MB inactivated all tested viruses on respirator material, albeit with varying efficiency. Virus applied to respirator material pre-treated with MB was also inactivated, thus MB pretreatment may potentially protect respirator wearers from virus exposure in real-time.
These results demonstrate that photoactivated MB represents a cost-effective, rapid, and widely deployable method to decontaminate N95 respirators for reuse during supply shortages.
COVID-19 大流行导致全球范围内 N95 呼吸器短缺，促使开发了消毒方法以实现有限的重复使用。缺乏可靠供应链的国家也将受益于安全重复使用个人防护设备的能力。亚甲蓝（MB）是一种具有已证明的抗菌活性的光激活染料，用于消毒血浆。使用光激活 MB 对呼吸器进行消毒不需要特殊设备，因此在疫情爆发期间在现场使用具有吸引力。
我们研究了使用光激活 MB 和导致 COVID-19 的 SARS-CoV-2 的 3 种变体以及世界卫生组织的 4 种优先病原体（埃博拉病毒、中东呼吸综合征冠状病毒、尼帕病毒和拉萨病毒）对 N95 和 KN95 呼吸器进行消毒。还测试了预处理呼吸材料对病毒的灭活作用。
光激活 MB 使所有测试的病毒在呼吸材料上失活，但效率不同。MB 预处理过的呼吸材料上的病毒也被灭活，因此 MB 预处理可能有潜力实时保护呼吸器佩戴者免受病毒暴露。
这些结果表明，光激活 MB 代表了一种具有成本效益、快速且广泛可部署的方法，可以在供应短缺期间对 N95 呼吸器进行消毒以重复使用。
