According to research by UCL scientists and colleagues, N.C. Credit: CDC / Deborah Cartagena
Scientists hope that the new methods can overcome the acute shortage of personal protective equipment.
N95 respirator, which is widely worn by health care workers treating patients COVID-19 And designed to be used only once, UCLA can be effectively decontaminated and used three times, according to research by scientists and colleagues.
An initial study version of their study has been published online, with a full study in the journal in September. Emerging infectious diseases.
N95 respirators reduce exposure to airborne infectious agents, including SARS-CoV-2, The virus that causes COVID-19 and is a key component of personal protective devices used by clinical workers to prevent the spread of the virus. The critical shortage of these masks has led to efforts to find new decontamination methods that could increase their use.
“However, N95 respirators are designed for single use before respiratory disposal. In times of scarcity, N95 respirators can be re-activated and reused up to three times,” said James Lloyd-Smith, co-author of the study and Said the UCLA professor of ecology. And Evolutionary Biology. “But the integrity of the respirator’s screws and seals must be maintained.”
In a controlled laboratory setting, the researchers tested specific methods on small pieces of N95 filter fabric that came in contact with SARS-Covy-2. Methods include evaporation hydrogen peroxide, dry heating at 70 degrees Celsius (158 degrees) Fahrenheit), Ultraviolet light and 70% ethanol spray. All four methods removed traceable virus traces from N95 fabric test samples.
Investigators then treated perfectly intact, clean respirators with similar remedial methods to test the durability of their reuse. Employees with the national bodies of Rocky Mountain Laboratories of Health in Montana worked wearing a mask for two hours to determine if they had proper fit and seals on the face. Using the same procedure with each other, the scientists made each mask three times inadvisable.
Masks with evaporated hydrogen peroxide did not experience any failure, suggesting that they could potentially be reused three times, Loped-Smith said. Ultraviolet light and dry heat therapists began to show fit and seal problems after three disintegrations, suggesting that this respirator could potentially be reused twice.
The study authors concluded that evaporated hydrogen peroxide is the most effective method because no traces of the virus were detected after only 10 minutes of treatment. They found that ultraviolet light and dry heat are also acceptable decontamination processes, as long as the methods are applied for at least 60 minutes.
Ethanol spray, scientists found, damaged the integrity of the respiratory tract and seals after two sessions, and they do not recommend it to decompose N95 respirators.
Researchers have strongly suggested that anyone who reconstitutes an N95 respirator should examine the fit and seal on the face closely before reusing it.
Reference: Robert J. Fisher, Dillon H. Morris, Neltje van Were Doremelen, Shanda Serchet, m. “N95 Respirator Decontamination and SUSL SARS-Co-2 Virus Re-Efficacy” by Jeremy Mattson, Trenton Bushmaker, Cloud Quay Yinda, Stephanie N. Seafert, Amandine Gamble, Brandy Ann. Williamson, Seth D. Judson, Emmy D. Witt, James O. Lloyd-Smith and Vincent J. Munster, 3 June 2020, Emerging infectious diseases.
DOI: 10.3201 / eid2609.201524
Co-authors of the study include Amandine Gamble, a UCLA postdoctoral researcher at Lond-Smith’s laboratory, as well as researchers at Rocky Mountain Laboratories, part of NIH’s National Institute of Allergy and Infectious Diseases.
Sources of funding include the National Institute of Allergy and Infectious Diseases, the Defense Advanced Research Projects Agency, and the National Science Foundation.
In a widely cited study, Lloyd-Smith and colleagues noted in March that the virus that causes COVID-19 stays on the surface and in aerosols for many hours to days.
