Scientists Want To Learn More About Using UV Lights To Fight The Spread Of COVID-19

Musa Firat recently installed a “killing zone” near the ceiling of a dining room in a Seattle area restaurant. At this location, a band of invisible electromagnetic energy penetrates the air and is ready to disarm coronaviruses and other drifting dangerous pathogens. Upward with small airborne particles.

Philat’s new system Century technology Fencing Freedom from Infectious Diseases: The energy wave of ultraviolet light (also known as energy UV, or GUV) is provided in adequate amounts to clear viruses, bacteria, and other microbes.

Studies have already shown that germicidal UV can effectively inactivate transmitted airborne microbes measles, tuberculosis And SARS-CoV-1, A close relative of the new coronavirus. Worry now attachment Coronavirus causing COVID-19 is easy Sent Some researchers and physicians hope that this technique will be re-adopted to help disinfect high-risk indoor environments through microscopic airborne particles known as aerosols.

“I thought it was a great idea, and I want my customers to be safe,” said casual restaurant Firat. Marulina’s Mediterranean Kitchen, 20 minutes south of downtown Seattle.

The United States is working on ways to stop the spread of highly infectious viruses, and UV second hand To Decontamination The surface of public transport and hospitals where infectious splashes may have landed, and disinfect N95 mask for reuse. But so far, providing continuous air disinfection using this technology is outside most mainstream policy-setting conversations about coronaviruses.

Experts attribute this to a combination of factors: misunderstandings about UV safety, lack of public awareness and technical know-how, concerns about the cost of introducing the technology, and the role of aerosols in the spread of coronaviruses. General resistance to.

Aerosols are tiny droplets that are emitted when someone exhales, talks, or coughs. Unlike large and heavy respiratory droplets that quickly drop to the ground, aerosols can remain in the air for long periods of time and travel indoors. If someone gets a virus this way, the process is called “airborne.”

It is already recognized that aerosols can spread coronaviruses during medical procedures. Therefore, healthcare professionals are advised to wear a mask (such as the N95 mask) that removes these small particles. Still, there is considerable debate about the potential spread of the virus via aerosols to other environments.

Recently, the problem of airborne transmission gained new urgency when a group of 239 scientists conducted research Was called The World Health Organization took the threat of infectious aerosols more seriously, arguing that “the lack of clear recommendations for control measures against airborne viruses has serious consequences.”

WHO officials admitted that more research was needed, but claimed that most infections did not occur this way.

As science continues to evolve, UV may emerge as an attractive defense against airborne infections, has a proven track record against pathogens, and reduces the risk of infectious aerosols accumulating in indoor environments such as schools and businesses. It can be deployed.

Welcome to “Killing Zone”

There are two clues to the new UV disinfection system at the Marulina restaurant. The subtle glow of the blue light above the black grid on the drop ceiling and the hand-chalked sign on the door proudly informs the diner. “Coronavirus disinfection here!”

The system was installed when the restaurant was closed during the Washington blockade. setup Are known Since the UV device is installed at a high position and is at an angle away from the person below, it is used as “sterilization UV for the upper part of the room”.

A ceiling fan circulates the air, ultimately pushing suspended virus particles that have accumulated in the dining space from the grated drop ceiling into a horizontally positioned UV light that pushes them into the blasting area with radiant energy.

The inspiration and technical assistance to the owners of Marlaina came from customer Bruce Davidson, a pulmonary physician who was Philadelphia’s “tuberculous empire” in the mid-’90s. At that time, the United States was working on the development of new tuberculosis, including strains resistant to existing drugs.

“We had no drugs or vaccines, so preventing infections was the most important part,” recalled Davidson, who now lives outside Seattle. At that time, UV light turned out to be an important strategy, and Davidson believes it will help again. “Currently, it should be placed in most indoor public spaces.”

To demonstrate the concept, Davidson lit a cigar inside Marlaina, showing the smoke dancing upwards and gathering in a ceiling space with a UV fixture.

“If someone is unaware of the coronavirus and is talking without a mask and without eating, then most of those particles will be drawn to the killing zone where they will circulate and bounce off,” Davidson said. Said. “Statistically, the risk to others will be very low.”

Study show Nearly 90% of the airborne particles of the previous coronavirus (SARS-CoV-1) are inactivated in about 16 seconds when exposed to UV as strong as a restaurant ceiling. Other viruses, such as adenovirus, are more resistant and require higher UV doses.

“It’s not perfect, but it offers perhaps the best solution for direct air disinfection in today’s pandemics,” he said. David Sline, A professor at Johns Hopkins University and a long-time researcher on germicidal UV radiation.

When used with proper ventilation, upper chamber GUVs are approximately 80% effective at expanding airborne tuberculosis. According to some research.. This is equivalent to changing the room air up to 24 times an hour.

However, widespread adoption of UV systems can be a daunting battle, Sleeney said. In the United States, scientists have turned their attention to powerful vaccines and drugs to combat infectious diseases, and in recent decades their interest in using UV for air disinfection has diminished.

Understanding aerosols and airborne penetration

UV can be a powerful weapon against airborne viruses, but so far it can only be used to prevent infection. People can get sick from the large, heavy droplets that are expelled through coughing and sneezing. They inhale those droplets directly or touch a surface contaminated with them, and then their eyes, nose or mouth.

UV also does not prevent someone from being exposed to infectious aerosols that have just emerged from an infected person. It also remains quite close to the body of the person Richard Corsi, the researcher, calls what the “near field” is.

“In that scenario, we are inhaling a very concentrated cloud of invisible small particles,” he said. course, Dean of the Macy College of Engineering & Computer Science at Portland State University. “You are getting a fairly significant dose in your respiratory system.”

According to Corsi, face masks and social distances are still needed to block larger respiratory droplets and remove some of the aerosols in the short distance, even if there is UV light on the top of the building. But Corsi said it was enough now evidence Coronavirus aerosol Floating in the air It is time to seriously consider the expanse of the air as it spreads throughout the room (“far away”).

An example of far field transmission is Study of Chinese restaurants Some diners seated at a nearby table have been infected with the COVID-19 virus, even though they have not been in close contact with “index case patients”. another evidence I came from a chorus practice on March 10th at Mount Vernon, Washington. Subsequent members of the group used hand sanitizers and took precautions to avoid hugging and shaking hands, but most singers became infected with the coronavirus.

In a letter to the WHO, scientists point out that the coronavirus that causes MERS may spread through aerosols, “and there are all reasons to expect it. [the COVID virus] Works the same. “

Understand technology and safety

Germicidal UV Use part of Electromagnetic spectrum It contains a short wave of radiant energy called UV-C. This wavelength is farther from the visible spectrum than other forms of UV light.

Think of it as giving the virus a deadly sunburn.

“We have very little practical experience demonstrating how effective it is. [in a pandemic] It is no longer used in this country and Western Europe. “Said Johns Hopkins, who chairs the recently announced Committee of Lighting Engineering. guidance With GUV.

Sliney recommends installing UVs in large ceiling stores, restaurants and grocery stores. “Needs vertical air exchange,” he said, and like a ceiling fan, it “doesn’t just sterilize the air in the headspace of a room.”

“No one doubts the effectiveness of germicidal UV light in killing small microbes and pathogens. If there’s a big controversy, I think it’s a safety misconception,” he said. Dr. Edward Nadel Professor of Harvard Medical School studying GUVs.

Although low doses of germicidal UV can cause eye and skin damage, he says that proper risk can be avoided by following proper guidelines. International guidelines warn against direct human exposure to UV-C, but consider skin cancer risk Very littleEspecially compared to longer wavelength UV which can penetrate deeper.

Will UV come back?

The interest in UV climbing raises concerns about sneaky products on the market and exaggerated claims about their effectiveness against viruses. Jim Marie, A professor at the University of New Hampshire, researching public health and disinfection.

Consumers need to be aware of marketing claims about “UV wands” or special “portals” that people pass through that can quickly ripple over the surface, and they probably tune correctly to inactivate the virus. It has not been done and may be dangerous.

Marie believes that there is not a viable market for supper-room GUVs outside of healthcare facilities, but he does support technology installation in the most risky environments, such as meat-packing plants and nursing homes. I am.

“I have a horrific deadly record with the coronavirus, so my intuition feels I should do whatever I can at those places,” he said.

The installation was relatively easy at the Marlaina restaurant.

The owner, Firat, bought four UV fixtures ($165 each), hired an electrician to install the fans, and bought a black grid plastic panel to enclose the ceiling space where the UV was installed.

Firat still encourages customers to wear masks and maintain social distance. But he said UV is part of the atmosphere.

“It’s more modern and clean, the reaction is great and absolutely fantastic,” he said.

This story is part of a partnership that includes: NPR And Kaiser Health News.