“Disinfection Tunnels” Are Popping Up Around the World, Fueled By Misinformation and Fear
In an incident that sparked widespread outrage across India in late March, officials in the north Indian state of Uttar Pradesh sprayed hundreds of migrant workers, including women and children, with a chemical solution to sanitize them, in a misguided attempt to contain the spread of the novel coronavirus.
Since COVID-19 is a respiratory disorder, disinfecting a person's body or clothes cannot protect them from contracting the novel coronavirus, or help in containing the pathogen's spread.
Health officials reportedly doused the group with a diluted mixture of sodium hypochlorite – a bleaching agent harmful to humans, which led to complaints of skin rashes and eye irritation. The opposition termed the instance 'inhuman', compelling the state government to order an investigation into the mass 'chemical bath.'
"I don't think the officials thought this through," says Thomas Abraham, a professor with The University of Hong Kong, and a former consultant for the World Health Organisation (WHO) on risk communication. "Spraying people with bleach can prove to be harmful, and there is no guideline … that recommends it. This was some sort of a kneejerk reaction."
Although spraying individuals with chemicals led to a furor in the South Asian nation owing to its potential dangers, so-called "disinfection tunnels" have sprung up in crowded public places around the world, including malls, offices, airports, railway stations and markets. Touted as mass disinfectants, these tunnels spray individuals with chemical disinfectant liquids, mists or fumes through nozzles for a few seconds, purportedly to sanitize them -- though experts strongly condemn their use. The tunnels have appeared in at least 16 countries: India, Malaysia, Scotland, Albania, Argentina, Colombia, Singapore, China, Pakistan, France, Vietnam, Bosnia and Herzegovina, Chile, Mexico, Sri Lanka and Indonesia. Russian President Vladimir Putin even reportedly has his own tunnel at his residence.
While U.S. visitors to Mexico are "disinfected" through these sanitizing tunnels, there is no evidence that the mechanism is currently in use within the United States. However, the situation could rapidly change with international innovators like RD Pack, an Israeli start-up, pushing for their deployment. Many American and multinational companies like Stretch Structures, Guilio Barbieri and Inflatable Design Works are also producing these systems. As countries gradually ease lockdown restrictions, their demand is on the rise -- despite a stringent warning from the WHO against their potential health hazards.
"Spraying individuals with disinfectants (such as in a tunnel, cabinet, or chamber) is not recommended under any circumstances," the WHO warned in a report on May 15. "This could be physically and psychologically harmful and would not reduce an infected person's ability to spread the virus through droplets or contact. Moreover, spraying individuals with chlorine and other toxic chemicals could result in eye and skin irritation, bronchospasm due to inhalation, and gastrointestinal effects such as nausea and vomiting."
Disinfection tunnels largely spray a diluted mixture of sodium hypochlorite, a chlorine compound commonly known as bleach, often used to disinfect inanimate surfaces. Known for its hazardous properties, the WHO, in a separate advisory on COVID-19, warns that spraying bleach or any other disinfectant on individuals can prove to be poisonous if ingested, and that such substances should be used only to disinfect surfaces.
Considering the effect of sodium hypochlorite on mucous membranes, the European Centre for Disease Prevention and Control, an EU agency focussed on infectious diseases, recommends limited use of the chemical compound even when disinfecting surfaces – only 0.05 percent for cleaning surfaces, and 0.1 percent for toilets and bathroom sinks. The Indian health ministry also cautioned against spraying sodium hypochlorite recently, stating that its inhalation can lead to irritation of mucous membranes of the nose, throat, and respiratory tract.
In addition to the health hazards that such sterilizing systems pose, they have little utility, argues Indian virologist T. Jacob John. Since COVID-19 is a respiratory disorder, disinfecting a person's body or clothes cannot protect them from contracting the novel coronavirus, or help in containing the pathogen's spread.
"It's a respiratory infection, which means that you have the virus in your respiratory tract, and of course, that shows in your throat, therefore saliva, etc.," says John. "The virus does not survive outside the body for a long time, unless it is in freezing temperatures. Disinfecting a person's clothes or their body makes no sense."
Disinfection tunnels have limited, if any, impact on the main modes of coronavirus transmission, adds Craig Janes, director, School of Public Health and Health Systems at Canada's University of Waterloo. He explains that the nature of COVID-19 transmission is primarily from person-to-person, either directly, or via an object that is shared between two individuals. Measures like physical distancing and handwashing take care of these transmission risks.
"My view of these kinds of actions are that they are principally symbolic, indicating to a concerned population that 'something is being done,' to martial support for government or health system efforts," says Janes. "So perhaps a psychological benefit, but I'm not sure that this benefit would outweigh the risks."
"They may make people feel that their risk of infection has been reduced, and also that they do not have to worry about infecting others."
A recent report by Health Care Without Harm (HCWH), an international not-for-profit organization focused on sustainable health care around the world, states that disinfection tunnels have little evidence to demonstrate their efficacy or safety.
"If the goal is to reduce the spread of the virus by decontaminating the exterior clothing, shoes, and skin of the general public, there is no evidence that clothes are an important vector for transmission. If the goal is to attack the virus in the airways, what is the evidence that a 20-30 second external application is efficacious and safe?" the report questions. "The World Health Organization recommends more direct and effective ways to address hand hygiene, with interventions known to be effective."
If an infected person walks through a disinfection tunnel, he would still be infectious, as the chemicals will only disinfect the surfaces, says Gerald Keusch, a professor of medicine and international health at Boston University's Schools of Medicine and Public Health.
"While we know that viruses can be "disinfected" from surfaces and hands, disinfectants can be harmful to health if ingested or inhaled. The underlying principle of medicine is to do no harm, and we always measure benefit against risk when approving interventions. I don't know if this has been followed and assessed with respect to these devices," says Keusch. "It's a really bad idea."
Experts warn that such tunnels may also create a false sense of security, discouraging people from adopting best practice methods like handwashing, social distancing, avoiding crowded places, and using masks to combat the spread of COVID-19.
"They may make people feel that their risk of infection has been reduced, and also that they do not have to worry about infecting others," says Janes. "These are false assumptions, and may lead to increasing rather than reducing transmission."
Fast for Longevity, with Less Hunger, with Dr. Valter Longo
You’ve probably heard about intermittent fasting, where you don’t eat for about 16 hours each day and limit the window where you’re taking in food to the remaining eight hours.
But there’s another type of fasting, called a fasting-mimicking diet, with studies pointing to important benefits. For today’s podcast episode, I chatted with Dr. Valter Longo, a biogerontologist at the University of Southern California, about all kinds of fasting, and particularly the fasting-mimicking diet, which minimizes hunger as much as possible. Going without food for a period of time is an example of good stress: challenges that work at the cellular level to boost health and longevity.
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If you’ve ever spent more than a few minutes looking into fasting, you’ve almost certainly come upon Dr. Longo's name. He is the author of the bestselling book, The Longevity Diet, and the best known researcher of fasting-mimicking diets.
With intermittent fasting, your body might begin to switch up its fuel type. It's usually running on carbs you get from food, which gets turned into glucose, but without food, your liver starts making something called ketones, which are molecules that may benefit the body in a number of ways.
With the fasting-mimicking diet, you go for several days eating only types of food that, in a way, keep themselves secret from your body. So at the level of your cells, the body still thinks that it’s fasting. This is the best of both worlds – you’re not completely starving because you do take in some food, and you’re getting the boosts to health that come with letting a fast run longer than intermittent fasting. In this episode, Dr. Longo talks about the growing number of studies showing why this could be very advantageous for health, as long as you undertake the diet no more than a few times per year.
Dr. Longo is the director of the Longevity Institute at USC’s Leonard Davis School of Gerontology, and the director of the Longevity and Cancer program at the IFOM Institute of Molecular Oncology in Milan. In addition, he's the founder and president of the Create Cures Foundation in L.A., which focuses on nutrition for the prevention and treatment of major chronic illnesses. In 2016, he received the Glenn Award for Research on Aging for the discovery of genes and dietary interventions that regulate aging and prevent diseases. Dr. Longo received his PhD in biochemistry from UCLA and completed his postdoc in the neurobiology of aging and Alzheimer’s at USC.
Show links:
Create Cures Foundation, founded by Dr. Longo: www.createcures.org
Dr. Longo's Facebook: https://www.facebook.com/profvalterlongo/
Dr. Longo's Instagram: https://www.instagram.com/prof_valterlongo/
Dr. Longo's book: The Longevity Diet
The USC Longevity Institute: https://gero.usc.edu/longevity-institute/
Dr. Longo's research on nutrition, longevity and disease: https://pubmed.ncbi.nlm.nih.gov/35487190/
Dr. Longo's research on fasting mimicking diet and cancer: https://pubmed.ncbi.nlm.nih.gov/34707136/
Full list of Dr. Longo's studies: https://pubmed.ncbi.nlm.nih.gov/?term=Longo%2C+Valter%5BAuthor%5D&sort=date
Research on MCT oil and Alzheimer's: https://alz-journals.onlinelibrary.wiley.com/doi/f...
Keto Mojo device for measuring ketones
Silkworms with spider DNA spin silk stronger than Kevlar
Story by Freethink
The study and copying of nature’s models, systems, or elements to address complex human challenges is known as “biomimetics.” Five hundred years ago, an elderly Italian polymath spent months looking at the soaring flight of birds. The result was Leonardo da Vinci’s biomimetic Codex on the Flight of Birds, one of the foundational texts in the science of aerodynamics. It’s the science that elevated the Wright Brothers and has yet to peak.
Today, biomimetics is everywhere. Shark-inspired swimming trunks, gecko-inspired adhesives, and lotus-inspired water-repellents are all taken from observing the natural world. After millions of years of evolution, nature has quite a few tricks up its sleeve. They are tricks we can learn from. And now, thanks to some spider DNA and clever genetic engineering, we have another one to add to the list.
The elusive spider silk
We’ve known for a long time that spider silk is remarkable, in ways that synthetic fibers can’t emulate. Nylon is incredibly strong (it can support a lot of force), and Kevlar is incredibly tough (it can absorb a lot of force). But neither is both strong and tough. In all artificial polymeric fibers, strength and toughness are mutually exclusive, and so we pick the material best for the job and make do.
Spider silk, a natural polymeric fiber, breaks this rule. It is somehow both strong and tough. No surprise, then, that spider silk is a source of much study.The problem, though, is that spiders are incredibly hard to cultivate — let alone farm. If you put them together, they will attack and kill each other until only one or a few survive. If you put 100 spiders in an enclosed space, they will go about an aggressive, arachnocidal Hunger Games. You need to give each its own space and boundaries, and a spider hotel is hard and costly. Silkworms, on the other hand, are peaceful and productive. They’ll hang around all day to make the silk that has been used in textiles for centuries. But silkworm silk is fragile. It has very limited use.
The elusive – and lucrative – trick, then, would be to genetically engineer a silkworm to produce spider-quality silk. So far, efforts have been fruitless. That is, until now.
We can have silkworms creating silk six times as tough as Kevlar and ten times as strong as nylon.
Spider-silkworms
Junpeng Mi and his colleagues working at Donghua University, China, used CRISPR gene-editing technology to recode the silk-creating properties of a silkworm. First, they took genes from Araneus ventricosus, an East Asian orb-weaving spider known for its strong silk. Then they placed these complex genes – genes that involve more than 100 amino acids – into silkworm egg cells. (This description fails to capture how time-consuming, technical, and laborious this was; it’s a procedure that requires hundreds of thousands of microinjections.)
This had all been done before, and this had failed before. Where Mi and his team succeeded was using a concept called “localization.” Localization involves narrowing in on a very specific location in a genome. For this experiment, the team from Donghua University developed a “minimal basic structure model” of silkworm silk, which guided the genetic modifications. They wanted to make sure they had the exactly right transgenic spider silk proteins. Mi said that combining localization with this basic structure model “represents a significant departure from previous research.” And, judging only from the results, he might be right. Their “fibers exhibited impressive tensile strength (1,299 MPa) and toughness (319 MJ/m3), surpassing Kevlar’s toughness 6-fold.”
A world of super-materials
Mi’s research represents the bursting of a barrier. It opens up hugely important avenues for future biomimetic materials. As Mi puts it, “This groundbreaking achievement effectively resolves the scientific, technical, and engineering challenges that have hindered the commercialization of spider silk, positioning it as a viable alternative to commercially synthesized fibers like nylon and contributing to the advancement of ecological civilization.”
Around 60 percent of our clothing is made from synthetic fibers like nylon, polyester, and acrylic. These plastics are useful, but often bad for the environment. They shed into our waterways and sometimes damage wildlife. The production of these fibers is a source of greenhouse gas emissions. Now, we have a “sustainable, eco-friendly high-strength and ultra-tough alternative.” We can have silkworms creating silk six times as tough as Kevlar and ten times as strong as nylon.
We shouldn’t get carried away. This isn’t going to transform the textiles industry overnight. Gene-edited silkworms are still only going to produce a comparatively small amount of silk – even if farmed in the millions. But, as Mi himself concedes, this is only the beginning. If Mi’s localization and structure-model techniques are as remarkable as they seem, then this opens up the door to a great many supermaterials.
Nature continues to inspire. We had the bird, the gecko, and the shark. Now we have the spider-silkworm. What new secrets will we unravel in the future? And in what exciting ways will it change the world?