Category: Corona Virus

Ultraviolet radiation is a strong disinfectant

You may remember when US President Donald Trump suggested exposing coronavirus patients to UV (ultraviolet) light—or “just very powerful light”—to help treat them.

The use of UV light is not, in any way, a viable treatment for people infected with SARS-CoV-2. However, due to its powerful sterilisation abilities, this technology does have great potential for managing the COVID-19 pandemic in other ways.

What is UV light?

The visible light we see every day belongs in a unique region of the whole electromagnetic spectrum. The full spectrum is composed of radio waves, microwaves, infrared, visible light, ultraviolet, X-rays and gamma rays—all emitting and carrying energy.

Of these, ultraviolet (UV), X-ray and gamma rays are high-frequency waves. These can have serious consequences for our health.

The Sun emits three types of UV radiation: UVA, UVB and UVC. Prolonged UV exposure is associated with skin cancer. Thankfully, our planet’s atmosphere shields us from the majorityof the Sun’s UVB emissions and all UVC emissions.

Affordable and accessible

UVC has the ability to kill germs and is an alternative to chemical disinfection. UVC can be used to sterilise objects, water, surfaces and materials—whether it’s to clean your phone, a hospital floor, or an entire bus in China.

The technology needed to generate UVC is not new and there is no reason to suggest this technology could not be implemented cost-effectively. Several companies have developed an array of lamps, machines and even robots capable of sterilising a range of surfaces.

Isn’t is dangerous?

It’s well established UV radiation is carcinogenic (causes cancer) for humans.

Devices that emit UVC should be calibrated to ensure optimal microbial killing power and are more effective when placed close to the surface or object being treated. When turned off, UVC emission is halted, too.

As per the World Health Organisation’s advice, direct UVC exposure should not be used to disinfect any areas of the skin. Studies are under way to identify particular UVCs that are safe for human cells and still worthwhile as germicides.

Far-UVC (wavelengths between 207-222 nanometres) is promising as it can’t cross physiological barriers, such as the dead outer layer of our skin, or the eye’s outer (tear film) layer.

Nonetheless, UVC still poses risks to our health since our skin and eyes can have cuts and micro-lesions. This would expose susceptible cells in our body to the damaging radiation.

Can it kill COVID-19?

Our knowledge of what constitutes “suitable” UVC emission is growing. This includes knowledge of the proper germicidal UVC wavelength that can be applied to surfaces, the amount of light that reaches the surface, and the exposure time needed to completely sterilise the viral particles.

Research from 2002 confirmed UVC inactivated SARS (severe acute respiratory syndrome) after six minutes of exposure.

A more recent study (while not peer-reviewed) has shown UVC-based disinfection is helpful for stopping the SARS-CoV-2 virus from replicating. However, this depended on how much of the virus was present and how much UVC exposure it received.

The study centred on the efficiency of UVC to inactivate and inhibit the virus at low, medium and high concentrations. It found the highest viral concentrations required quite high UVC dosage.

Another study looking at a different type of coronavirus (SARS-CoV-1) provided further evidence of the utility of UVC disinfection. The authors of this work suggest UV technology may be the solution to filling gaps in the supply of personal protective equipment such as masks.

Overcoming major hurdles

Apart from being carcinogenic, another limitation on using UVC is its poor penetration. It only allows surface-level sterilisation of microbes (such as viruses, bacteria and fungi) by impacting their genetic material.

That said, as the pandemic continues, the deployment of UVC sanitising technology across sectors could greatly contribute to our awareness of the risks presented by microbial pathogens.

The safe implementation of UVC-based measures could undoubtedly enhance public health and even biosecurity. Beyond the novel coronavirus, this arsenal has great potential to prevent costly impacts of future pandemics, too.

But, while enthusiasm is high, there are obvious risks of direct exposure to humans, with consequences ranging from serious burns to cancer. These will need to be carefully managed.

The Realities of Disinfectant Lighting

Before President Donald Trump erroneously—and sarcastically, he later claimed—suggested the possibility of using “ultraviolet or just a very powerful light … inside the body” at a White House briefing in April as a potential treatment for COVID-19, scientific research in the use of UV light to combat pathogens was well underway. Given these comments and a heightened interest in disinfection due to the pandemic, the lighting community swiftly released webinars, FAQs, and press releases to offer guidance on the effectiveness, potential applications, and myths of using UV radiation to fight infection.

The Illuminating Engineering Society, a professional association for the lighting and design community, was one such organization to respond to the increased interest in germicidal UV lighting. The IES focused on UVC, which is currently considered the most effective range in the UV light wavelength spectrum in disinfection, but also can be the most hazardous to people exposed to it in uncontrolled settings. (Other wavelength ranges, including UVA, have also been shown to successfully kill or inactivate pathogens.) While versions of germicidal UV (GUV) have been used for surface disinfection since the late 1800s, interest in the technology increased following the 2014 Ebola virus outbreak in West Africa. When properly applied, GUV—which refers to short-wave UVC radiation in the 200-to- 280-nanometer range on the ultraviolet spectral band—has been shown to kill bacteria and spores and even deactivate viruses, such as SARS-CoV-2, which are nonliving infectious agents that replicate. (UVA, UVB, and UVC are all produced by the sun and pass through the ozone layer in varying quantities, with UVA being the most prevalent.)

The organization’s photobiology committee opted to convene a special subcommittee to address the topic, and after a few intense weeks published the “Germicidal Ultraviolet (GUV) – Frequently Asked Questions” report. “There is enough misleading information that we felt we really needed to address the typical questions people have,” medical physicist and committee chair David Sliney tells ARCHITECT.

“For viruses, very short wavelength UVC will break down its RNA, preventing the virus from replicating,” explain professor Mark Rea and senior research scientist Andrew Bierman, both at the Lighting Research Center at Rensselaer Polytechnic Institute in Troy, N.Y. “For bacteria, this direct action on its DNA will also prevent replication. The UV is absorbed by a chromophore, which creates intracellular reactive oxygen molecules, like hydrogen peroxide, that react with life-sustaining molecules.”

If the technology is used properly, luminaires outfitted with UVC light sources do not cause harm to occupants. Sliney remarks that the long-held belief that UVC causes skin cancer “is largely a myth.” However, direct exposure can cause uncomfortable eye conditions such as photokeratitis—also known as “welder’s flash”—or photoconjunctivitis if the luminaire is operated improperly. To avoid such conditions, the IES recommends the use of UVC light only in upper air germicidal fixtures, where the UVC source is positioned at least 7 feet high and directed at the ceiling to irradiate air as it circulates.

“Upper-room GUV disinfects large volumes of room air (above occupant heads) at once, resulting in high ‘equivalent’ air changes per hour in terms of air disinfection only,” the IES report explains. For rooms that do not have the requisite minimum ceiling height of 7 feet, designers might instead turn to UV lamps designed for installation inside air ducts for both residential and commercial HVAC units. However, this technology cannot help to limit the spread of disease between people when installed in ducts, cautions the IES in its report. “When UV is used in ducts, although it ensures that recirculated air does not have viable pathogens, it unfortunately does relatively little to prevent person-to-person transmission in a room where both an infectious source and other susceptible persons share the same air,” the organization writes. “For effective interruption of transmission, air disinfection has to occur in the same room where transmission is occurring.”

Many lighting manufacturers and technology companies have developed alternative options, leveraging LEDs and other light spectrums to offer antimicrobial effects without limiting occupation. GE Current, for example, sells a recessed LED luminaire that emanates UVA light at a wavelength of 365 nanometers, which is not visible to the human eye, as well as white light. The Boston-based manufacturer patented its technology, which enables fixtures that offer direct illumination and disinfection for occupied spaces, such as patient rooms and cafeterias, back in 2015. A study by Case Western Reserve University School of Medicine and the Cleveland VA Medical Center found that GE Current’s Lumination LED luminaires were effective in reducing MRSA (methicillin-resistant Staphylococcus aureus), E. coli, and bacteriophage MS2 by 80% to 90% for occupied patient rooms.

In 2019, Greenville, S.C.–based Hubbell Lighting launched its SpectraClean line of fixtures, which utilitize technology licensed from the University of Strathclyde in Glasgow, Scotland, that targets bacteria, molds, fungi, and yeast with 405-nanometer visible light, outside the UV spectrum. For use in commercial and industrial environments, SpectraClean features white and disinfectant lighting components, both of which are safe to operate in occupied spaces.

Since its creation in 2012, Troy, N.Y.–based LED technology company Vital Vio has also been providing bacteria-control lighting. “We are able to replace overhead lighting with [fixtures] that [create] inhospitable environments for germs, just through lighting,” founder Colleen Costello tells ARCHITECT. The company’s VioSafe White Light Disinfection technology targets strep, MRSA, E. coli, and salmonella, and is available in Ellumi Lighting residential fixtures.

Circling back to the the question on everyone’s minds these days: Are any of these technologies effective in combating the novel coronavirus? While none of the LED or UVA fixtures mentioned have proven effective against SARS-CoV-2, manufacturers are reporting increased interest from new and existing customers. Hubbell senior product manager Jeff McClow says that up to 75% of his time is now dedicated to presenting and holding trainings around the SpectraClean technology, up from 10% before the pandemic took hold. Vital Vio’s Costello also reports a significant uptick in demand and inquiries. “Institutions that had concerns or risks around germs have more of an urgency to add new tools to their arsenal,“ she says, “and folks who didn’t have it on their radar are now beginning to look at what new tools are available for us to adjust to this new normal.”

Rea and Bierman also note the benefits of existing disinfectant technology for limiting secondary infections for those who have been hospitalized with the novel coronavirus. “One of the problems with COVID- 19 is that it’s lethal not just from the virus itself, but it then makes people prone to secondary infections, particularly like bacterial pneumonia,” Rea said in an April webinar hosted by the Lighting Research Center. “If UVA can mitigate that bacterium, then you’re going to have a much less lethal infection from COVID-19.”

However, lighting researchers are concerned that users don’t fully understand the technology’s limitations, and that users will have “a false sense of security” after installing GUV or other UV technology, IES’s Sliney worries. Bierman and Rea concur. “The greatest misconception about the use of UV light for disinfection is that it will kill viruses just because it is nearby,“ they explain. “This is a line-of-sight technology; anything in a shadow will not be affected by the UV.”

To effectively utilize disinfectant lighting, users must understand that it is a complementary technology. “The area needs to be clean for the lighting to be effective,” McClow says. This means that any soil or dust must first be cleansed from surfaces in order to allow for direct illumination.

Duration of exposure and space dimensions are also critical considerations. Hubbell’s SpectraClean technology requires between six and 24 hours of operation to kill 99% of the targeted pathogens. According to McClow, the requisite time varies with factors such as the number of disinfectant fixtures in a space, ceiling height, and the distance from a fixture to surfaces. Like Hubbell and Vital Vio, GE Current recommends replacing most traditional lighting with disinfectant options in high-risk areas to maximize the benefits of its technology, which also calls for eight to 24 hours of usage. “UV light has to hit the surfaces that you want to disinfect,” says Dan Jenkins, GE Current general manager of product management. “You want to consider a layout to make sure that the surfaces you’re interested in disinfecting are being illuminated.” Some of these fixtures are also equipped with various settings, allowing for more intensive periods of disinfection. (In this case, users sacrifice white light for a more noticeable violet UV hue for certain luminaires.)

Like much of the scientific community, while manufacturers are turning their efforts to COVID-19, no major advancements have been reported. “You have to be careful if something is going to kill COVID-19, it also likely is dangerous to be used around people,” Costello warns.

Available for specification now, but potentially with delays due to COVID-19-related supply chain issues, these products are sold at a premium compared to conventional fixture prices. Additionally, the disinfectant settings often consume more energy than a standard luminaire, a factor that could impact a building owner’s bottom line. Hubbell, for one, approximates a 10W energy consumption difference between its traditional architectural troffer and a troffer fitted with SpectraClean capabilities.

However, as attention to environmental cleanliness and sanitation reach unprecedented levels, the business case for installing such germicidal luminares in health care environments and school cafeterias, and even above shopping cart bays for overnight disinfection in grocery stores has never been better.

Imaging Equipment Playing Key Role In Battling Covid-19

It seems the Coronavirus continues to spread across the world, impacting everything from daily life to the global economy. In these challenging times, the healthcare sector plays a particularly important role. In addition to protective clothing, respiratory masks and respirators, the ability to test rapidly and accurately is vital. However, rapid testing demands the availability of various laboratory analysers. Meeting the demand for analytical instruments requires that manufacturers continue production, to ensure the continuous supply of critical components across the world.

How to fight the virus?
Researchers around the globe are striving to develop an effective vaccine against the Coronavirus, but this still requires time. To combat the further spread of the coronavirus efficiently, immediate detection of the virus is of crucial importance. The aim is to reduce the chain of infection and thus the infection rate. But to identify who is and who is not infected requires that as many tests as possible are performed. Tedros Adhanom Ghebreyesus, head of the World Health Organisation (WHO), famously said during a press conference in March: ‘Test, test, test’.

Rapid tests and test analyzers
To test thousands of people, thousands of rapid tests are required, which in turn calls for great numbers of analytical devices for their evaluation. One common analysis method of these devices is the polymerase chain reaction (PCR). This method is widely used in molecular biology to multiply the patient’s DNA.

How does the PCR test work?
First, a smear is taken from the patient’s mouth, nose or throat. This sample is then sent to a laboratory. Each virus can be identified by a specific characteristic section of its genetic material. However, the quantity of the genetic material from the smear must be multiplied in order for there to be sufficient material to determine whether the pathogen is present or not. For this purpose, so-called thermocyclers are used, which initiate the polymerase chain reaction. In 30 to 50 cycles, the DNA is amplified exponentially.

If the pathogen is present in the sample, its genetic material will multiply and will be detected. If there is no genome of the pathogen, it will not go through the multiplication process and therefore not be detected. Using a fluorescence dye, the amplification of the pathogen genome can be monitored in real time. This is called real-time PCR.

It usually takes several days before the patient receives the test result. To send the sample to the laboratory takes the longest time, the test itself takes up to five hours.

Medical imaging as a further diagnostic tool
Severe cases of Covid-19 are associated with pneumonia, which can lead to changes in lung tissue. As a further diagnostic tool of coronavirus, medical imaging techniques such as computed tomography (CT) and conventional radiography of the thorax are used. Changes of lung tissue are visible in the images obtained through these methods. In some cases, the pneumonia associated changes of lung tissue are already visible despite the test results of PCR being negative. With computed tomography or thorax x-rays, the severity of the disease can be assessed and the clinical indication in severe cases monitored.

Compared to PCR, an advantage of medical imaging is that the results are available immediately. On the other hand, ionising radiation is used in CT and X-Ray, so the health benefit for the patient must outweigh the radiation risk.

Subway Trains and Buses in NYC Disinfected by UVC to Fight against Coronavirus Infection

The Metropolitan Transportation Authority (MTA) in New York City is using UV lamps to sanitize subway cars and buses for COVID-19 infection prevention, reported New York Daily News.

MTA announced that it will close the subway system from one to five a.m. every day since May 6, 2020 to deep clean and disinfect all the trains and buses to combat coronavirus. One of its disinfecting solution is using UV lamps to deliver UVC radiation for diminishing bacteria, viruses and other pathogens in the cars.

The disinfection project applying UV lamps was supported by MTA’s partnership with Columbia University. The UV lights will be tested on part of the subway trains and buses since May 11, 2020. The project would be expanded if researchers at Columbia University confirm the effectiveness afterward.

David Brenner, director of Columbia University’s Center for Radiological Research, noted that his research team is working on “far UVC” technology which can wipe out COVID-19 without causing harm to human body. Compared to the commonly known germicidal UV light with wavelength between 250nm to 280nm, far UVC light has shorter wavelength with the range of 205 to 230 nm and cannot reach or damage living human cells but can still kill viruses in the air or on surfaces.

Brenner said far-UVC light could be a game changer in the fight against COVID-19 as “it can be safely used in occupied public spaces, and it kills pathogens in the air before we can breathe them in.”

Coronavirus ‘Light It Blue’ Campaign Gives Thanks To Essential Workers

Hundreds of businesses and venues nationwide express gratitude to the front liners

Last Thursday was the #Light It Blue campaign as communities across the country, and even the world, spotlighted historic buildings, major sports stadiums and event venues, national landmarks and even Niagara Falls in blue lighting as a show of gratitude for health care professionals, first responders and essential workers caring for people on the front lines during the COVID-19 pandemic.

The #LightItBlue and #MakeItBlue movement began in the United Kingdom as major landmarks were lighted throughout the country in salute to health care providers. When introduced in the United States, support for the concept was impressive. The NFL joined the party. Mayors jumped on board. Major corporations lighted their headquarters.

Estimates are that more than 100 sites in New York City, home to the highest numbers of the coronavirus patients, and more than 400 other sites across America turned on the lights at 8 pm local time last Thursday. This age of LED lighting made the effort all the more dramatic.

“We hope it just creates this giant hug for all the health care workers and essential workers,” Michael Fiur, one of the Light It Blue campaign’s organizers and an internationally renowned entertainment producer, told CBS New York.

To name just a few prominent spots which embraced the group hug, let’s salute Arlington’s Globe Life Field, new home of the Texas Rangers whenever Major League Baseball resumes in its regular stadiums; Houston’s City Hall and all its major sports stadiums; Dallas’ Reunion Tower and Omni Hotel. And those are just some of the stunning shots corralled from Instagram.

Take a closer look at this new wave of blue, a symbol of heartfelt appreciation and thanks, that extended across the country to include Seattle’s Space Needle, Walt Disney World, Niagara Falls and more:

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