UV Flashlamp System Aids Ebola Disinfection
Justine Murphy, Editor
SAN ANTONIO, Dec. 5, 2014 — With the zap of a xenon UV flashlamp, numerous pathogens — including the Ebola virus — can be eradicated from surfaces around a room.
Developed by Xenex founder Dr. Mark Stibich, a new disinfection system has already been deployed in two U.S. hospitals where Ebola patients were treated, as well as at an Air Force base visited by personnel returning from fighting the outbreak in West Africa.
Based on air disinfection technology that has been used overseas to combat airborne tuberculosis, Xenex’s Germ-Zapping Robots work by pulsing xenon, an inert gas, at high intensity to produce shortwave ultraviolet (also called UV-C) flashes.
A Xenex Germ-Zapping Robot disinfects a hospital room. Courtesy of Xenex.
These bursts of light penetrate the cell walls of micro-organisms like Clostridium difficile (C. diff), MRSA, VRE and norovirus. Their DNA is instantly fused so the pathogens are unable to reproduce or mutate, effectively killing them on surfaces and in the air without any contact or use of chemicals.
The device takes 5 to 10 minutes to disinfect a typical hospital patient’s room, and has also demonstrated the ability to quickly destroy enveloped viruses, such as Ebola.
“When the Ebola virus arrived in the U.S., we realized we needed to validate the robot’s efficacy against it in a lab,” Stibich said. “Third-party lab testing against Ebola surrogates confirmed that the robot can achieve more than a 4 log reduction of the virus in a 5-minute cycle at the same 2-m distance as our other protocols.”
Xenex’s xenon technology has proved faster and hundreds of times more intense than existing UV systems that employ toxic mercury or hydrogen peroxide, Stibich said. Pulsed xenon emits high intensity UV-C light across a broad germicidal spectrum (200 to 320 nm), while mercury devices cover just a single wavelength of 253 nm.
Xenon UV technology has been more effective not only because of that broad spectrum, but also in the four types of cellular damage it delivers when zapping throughout a room — photohydration (pulling water molecules into the DNA to prevent its folding), photosplitting (breaking the backbone of the DNA), photodimerization (DNA damage that prevents replication) and photo crosslinking (cellular wall damage that causes cells to break down).
“This enables our Germ-Zapping Robots to disinfect healthcare facilities in a fraction of the time it takes for mercury bulb devices to disinfect rooms,” Stibich said. “Room turnover time is a big deal for hospitals — and because our robots work so quickly, they can disinfect many rooms per day.”
The device has been able to disinfect as many as 62 rooms in a 24-hour period. It is already used in 250 hospitals and U.S. Department of Veterans Affairs and Department of Defense facilities nationwide, including at the Texas Health Presbyterian Hospital Dallas and the University of Nebraska Medical Center, where Ebola patients have been treated.
“We have been contacted by hundreds of hospitals who would like robots in preparation for potential exposure to a patient with Ebola or a different emerging pathogen or superbug like EV-68,” he said.
The system could soon find its way overseas, namely in Africa.
“We’ve been in talks with several relief organizations and government agencies about how we could support their efforts in Africa,” Stibich said. “It hasn’t happened as quickly as we’d like, but we have robots lined up and ready to ship overseas.”
Xenex recently supplied its system to the medical group at Langley Air Force Base in Virginia, where military personnel have been returning from West Africa following operations there to help fight the Ebola outbreak. This group, along with other military treatment facilities, plans to add the machine to their disaster preparedness arsenal.
For more information, visit www.xenex.com.
- A rare gas used in small high-pressure arc lamps to produce a high-intensity source of light closely resembling the color quality of daylight.
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