Ultraviolet radiation is a strong disinfectant. It may be what our schools, hospitals and airports need


Lotti Tajouri, Bond University; Mariana Campos, Murdoch University; Rashed Alghafri, Bond University, and Simon McKirdy, Murdoch University

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 majority of 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.

Read more:
Mobile phones are covered in germs. Disinfecting them daily could help stop diseases spreading

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.

Read more:
What is a virus? How do they spread? How do they make us sick?

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 Conversation

Lotti Tajouri, Associate Professor, Biomedical Sciences, Bond University; Mariana Campos, Lecturer and Researcher, Harry Butler Institute, Murdoch University; Rashed Alghafri, Honorary Adjunct Associate Professor, Health Sciences and Medicine, Bond University, and Simon McKirdy, Professor of Biosecurity, Murdoch University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

No, 5G radiation doesn’t cause or spread the coronavirus. Saying it does is destructive


Stanley Shanapinda, La Trobe University

A conspiracy theory claiming 5G can spread the coronavirus is making the rounds on social media. The myth supposedly gained traction when a Belgian doctor linked the “dangers” of 5G technology to the virus during an interview in January.

Closer to home, Facebook group Stop5G Australia (with more than 31,700 members) has various posts linking the disease’s spread to 5G technology.

Members of the Stop5G Australia Facebook group share posts and videos claiming 5G helps spread COVID-19.

Peddling such misinformation is not only wrong, it’s destructive.

The Guardian reported that since Thursday at least 20 mobile phone masts across the UK have been torched or otherwise vandalised. Mobile network representative MobileUK published an open letter stating:

We have experienced cases of vandals setting fire to mobile masts, disrupting critical infrastructure and spreading false information suggesting a connection between 5G and the COVID-19 pandemic.

Celebrities – stick to what you know

Many outlets and people have rushed to debunk this myth, including federal minister for communications, cyber safety and the arts Paul Fletcher. But myriad groups and public figures continue to perpetuate it.

Actor Woody Harrelson and singer Keri Hilson have both shared content with fans suggesting a link between 5G and COVID-19.

Stop5G Australia members have claimed the Ruby Princess cruiseliner’s link to 600 reported infections and 11 deaths is because cruises are “radiation saturated”. That’s wrong.

A screenshot of posts from the Stop5G Australia Facebook group.

While cruise passengers can access roaming wifi services on board, these are not 5G services. Maritime cruises have yet to implement 5G technology.

One petition is calling on the Australia government to stop 5G’s rollout because the technology can supposedly “negatively affect your immune system” (a claim for which there is exactly zero evidence). It has received more than 27,000 signatures.

How 5G radio signals (radiation) work

The difference between 5G and previous generations of mobile services (4G, 3G) is that the latter use lower radio frequencies (below the 6 gigahertz range), whereas 5G also uses frequencies in the 30–300 gigahertz range.

This diagram shows different frequencies along the electromagnetic spectrum.
Australian Radiation Protection and Nuclear Safety Agency/AUS GOV., Author provided

In the 30-300 gigahertz range, there’s not enough energy to break chemical bonds or remove electrons when in contact with human tissue. Thus, this range is referred to as “non-ionising” electromagnetic radiation.

It’s approved by the federal government’s Australian Radiation Protection and Nuclear Safety Agency as not having the negative health effects of more intense radiation.

Read more:
There’s no evidence 5G is going to harm our health, so let’s stop worrying about it

Radiation can come into contact with the skin, for example, when we put a 5G mobile to our ear to make a call. This is when we’re most exposed to non-ionising radiation. But this exposure is well below the recommended safety level.

5G radiation can’t penetrate skin, or allow a virus to penetrate skin.
There is no evidence 5G radio frequencies cause or exacerbate the spread of the coronavirus.

Also, the protein shell of the virus is incapable of hijacking 5G radio signals. This is because radiation and viruses exist in different forms that do not interact. One is a biological phenomenon and the other exists on the electromagnetic spectrum.

5G radio waves are called millimetre waves, because their wavelength is measured in millimetres. Because these waves are short, 5G cell towers need to be relatively close together – about 250 metres apart. They are organised as a collection of small cells (a cell is an area covered by radio signals).

For 5G to cover a larger geographic area, more base stations are needed in comparison to 4G. This increase in the number of base stations, and their proximity to humans, is one factor that may stir unfounded fears about 5G’s potential health impacts.

Your phone may be dangerous, but its radiation isn’t

COVID-19 spreads through small droplets released from the nose or mouth of an infected person when they cough, spit, sneeze, talk or exhale. Transmission occurs when the droplets come into contact with the nose, eyes or mouth of a healthy person.

So if an infectious person speaks through a phone held near their mouth, enough infectious droplets may land on its surface to make it capable of spreading the virus. This is why it’s not advisable to share mobiles during a pandemic. You should also regularly disinfect your mobile.

Read more:
Can I get coronavirus from mail or package deliveries? Should I disinfect my phone?

Why are we having this discussion?

To many of us, it’s obvious a human virus can’t spread via radio signals, and such a conspiracy may be linked to a wider distrust of the government in general.

Addressing this myth is critical as property is now being damaged, and individuals attacked. Physical and verbal threats to broadband engineers can be added to a long list of assaults on health workers.

At a time when millions are relying on fast internet to work and study from home, vital telecommunications infrastructure is at risk of being destroyed. Conspiracy theories have motivated arson attacks on 5G towers in Belfast, Liverpool and Birmingham.

Youtube has announced it will devote resources to removing content linking 5G technology to COVID-19.

The announcement came after fingers were pointed at one video, published on March 18 (and viewed more than 668,000 times), in which an American doctor claims incorrectly that Africa is less affected by COVID-19 because it’s not a 5G region. The video remained online at the time of publishing this article.

Correction: this article was amended to make clear that, while millimeter waves lie within the frequency range of 30–300 gigahertz, 5G technology is also rolled out at lower frequencies than this.The Conversation

Stanley Shanapinda, Research Fellow, La Trobe University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Japan: Earthquake and Tsunami Photos

The link below is to 20 unforgettable pictures of the disaster as posted in a National Geographic daily news article: