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Tel Aviv research: 99.9% of COVID-19 virus dead in 30 seconds with UV LEDs
The study is the first of its kind in the world.

Ultraviolet radiation is a common method of killing bacteria and viruses. Now, researchers from Tel Aviv University have proven that the novel coronavirus, SARS-CoV-2, can be killed efficiently, quickly and cheaply using ultraviolet (UV) light-emitting diodes (UV-LEDs) at specific frequencies.

“We discovered that it is quite simple to kill the coronavirus using LED bulbs that radiate ultraviolet light,” said Prof. Hadas Mamane, head of the Environmental Engineering Program at Tel Aviv University's School of Mechanical Engineering, who led the study with Prof. Yoram Gerchman and Dr. Michal Mandelboim.

She said that the UV-LED bulbs require less than half a minute to destroy more than 99.9% of the coronaviruses.
The study is the first of its kind in the world. An article about it was published earlier this month in the Journal of Photochemistry and Photobiology B: Biology.

The Jerusalem Post has written about Mamane many times. She presented this summer at the Boris Mints Institute 2020 Research Conference on her involvement in the construction of a 30-meter "green wall" at the university, which is meant to create a sustainable ecosystem for waste, energy and water.

The wall is also meant to act as a living laboratory to analyze the uses of greywater (wastewater generated from sinks, showers, baths, and washing machines) in absorbing carbon dioxide, as well as the effects on heat transfer and energy generation within old buildings that are prevalent in urban settings.

At the beginning of the coronavirus crisis, her research team developed an Israeli, low-cost, decentralized, nonpolluting means of producing ethanol – and thereby an alcohol-based hand sanitizer – from plant-based waste, such as municipal and agricultural trim, straw and residual paper fibers.

LEDs are available in a wide range of wavelengths, known as A, B and C, explained Mamane.

UV-A has a wavelength in the range of 315 nanometers (nm) to 400 nm. UV-B, also known as medium wave light, has a wavelength of 280-315 nm; UV-C has a wavelength of 200-280 nm.
UV-A is emitted by the sun (and artificial sources like tanning beds) and is weaker than UV-B and C. It has some human benefits, such as the creation of vitamin D, but it is also what causes sunburns and, in some cases, skin cancer.

UV-B and C radiation never really reaches humans naturally because these rays are absorbed by the earth’s ozone layer.
These ultraviolet wavelengths, which are what Tel Aviv researchers were examining, are especially effective in disinfection using UV-LED bulbs.

“We know, for example, that medical staff do not have time to manually disinfect, say, computer keyboards and other surfaces in hospitals – and the result is infection and quarantine,” said Mamane. “The disinfection systems based on LED bulbs, however, can be installed in the ventilation system and air conditioner, for example, and sterilize the air sucked in and then emitted into the room.”

She added that, "We are also developing, together with a scientist in North Western University a transparent coating that can be dipped or sprayed on surfaces and can kill viruses using visible light LEDs that are not dangerous and are used everywhere, providing another application for regular LEDs."

In her team’s research, they managed to kill the virus using cheaper and more readily available LED bulbs – 285 nm vs. 265 nm bulbs – which consume little energy and do not contain mercury like regular UV lamps.

She said that as the science develops, the industry will be able to make the necessary adjustments and install the bulbs in robotic systems, or air conditioning, vacuum and water systems, and thereby be able to efficiently disinfect large surfaces and spaces.

“Our research has commercial and societal implications,” Mamane said.
She added that her team had been working on UV-LEDs for a long time before coronavirus. But when COVID-19 surfaced, they tried to see if they could transfer their efforts to tackling the human coronavirus, studying the use of LEDs for killing corona at different frequencies.
She said the 285 nm LED is 15% to 30% less expensive and requires only a little more time to be effective.

“Anything that can reduce cost could help implementation,” she said.

She added that UV LEDs have an advantage because they can be turned on and off in an instant.
Mamane believes that this technology is the future, adding that she expects that by 2025, it will be cost effective enough to become mainstream.

“UV LEDs have a huge future,” she added. “Of course, as always, when it comes to ultraviolet radiation, it is important to make it clear to people that it is dangerous to try to use this method to disinfect surfaces inside homes. You need to know how to design these systems and how to work with them so that you are not directly exposed to the light.”

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Israel has vaccinated 1 million people against COVID-19, more than a tenth of its population, Prime Minister Benjamin Netanyahu said Friday, as the country’s inoculation drive cemented its status as the world’s most rapid thus far.

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Originally posted by CHAS:
I thought that had been shown in the US. The remaining question was, "Just where do you put the light?"

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Just last week, Israel was seen as a model coronavirus country, outstripping the rest of the world in the pace of vaccinating its citizens by a hefty margin.

But the virus had other ideas.

This week, Israel faces a tightened lockdown as infections have spiraled to more than 8,000 new cases a day, officials fear the more transmissible variant of the virus first identified in Britain is spreading rapidly and Israel’s vaccine supplies are running low.

The prospect that Israel would have the virus under control by spring, once promising, now seems uncertain. Health officials say that in the short term, at least, the vaccine campaign cannot compete with the soaring infection rates.

And the Palestinian Authority, which runs its own health care system in the occupied West Bank, has asked Israel for vaccines, prompting a debate over Israel’s responsibility to the Palestinians at a time when Israel’s vaccine supplies are dwindling.

“We are at the height of a global pandemic that is spreading at record speed with the British mutation,” Prime Minister Benjamin Netanyahu said in a video statement late Tuesday, justifying the government’s decision to impose a full national lockdown that will shutter most schools and all nonessential workplaces for at least two weeks.

“Every hour we delay, the quicker the virus is spreading, and it will exact a very heavy price,” he added.

The lockdown decision came after Prof. Eran Segal of the Weizmann Institute of Science in Rehovot, Israel, presented the government with the dire projection that without such action, Israel’s infection rate could rise to 46,000 new cases per day by February, a staggering number in a country with a population of about 9 million.

Government officials cited the variant discovered in Britain as one of the main reasons for imposing the tighter restrictions. Mr. Netanyahu said the variant was “leaping forward,” though not at the same pace as it has spread in Britain.

At least 30 cases of the variant have been identified in Israel by special sampling, scattered across 14 different towns and cities, but officials and experts said those tests were aimed at identifying the presence of the variant, not quantifying it, and the actual number of cases was likely much higher.

Many scientists believe that the variant is more transmissible, meaning it may spread more easily from one person to another.

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Israel’s largest healthcare provider on Sunday reported a 94% drop in symptomatic COVID-19 infections among 600,000 people who received two doses of the Pfizer’s vaccine in the country’s biggest study to date.

Health maintenance organization (HMO) Clalit, which covers more than half of all Israelis, said the same group was also 92% less likely to develop severe illness from the virus.

The comparison was against a group of the same size, with matching medical histories, who had not received the vaccine.

“It shows unequivocally that Pfizer’s coronavirus vaccine is extremely effective in the real world a week after the second dose, just as it was found to be in the clinical study,” said Ran Balicer, Clalit’s chief innovation officer.

He added that the data indicates the Pfizer vaccine, which was developed in partnership with Germany’s BioNTech, is even more effective two weeks or more after the second shot.

Researchers at the Weizmann Institute of Science, who have been tabulating national data, said on Sunday that a sharp decline in hospitalisation and serious illness identified earlier among the first age group to be vaccinated - aged 60 or older - was seen for the first time in those aged 55 and older.