Aerosol scientists say that the evidence points to airborne transmission of COVID-19 "beyond any reasonable doubt."
The organization's late March messaging, still available on social media, is a digital graphic saying, "FACT CHECK: COVID-19 is NOT Airborne".
Screenshot of WHO's Tweet from March 28, 2020 that is still published.
The petition asks for a course correct: "We, citizens of the world, request that the World Health Organization (WHO) recognize the compelling scientific evidence that SARS-CoV-2 spreads by aerosol transmission ("airborne") and urge the WHO to immediately develop and initiate clear recommendations to enable people to protect themselves."
In the vacuum of the WHO's inaction, aerosol scientists around the world scrambled to raise awareness of what they saw as a grave error.
"Almost immediately after that [March 28] announcement, we formed a group of 239 scientists from many countries and disciplines to convince them that they should acknowledge that there is airborne transmission, but we find that they are totally dead set against it," says Dr. Jose Jimenez, a chemistry professor at the University of Colorado at Boulder who has studied aerosols for 20 years. He supports the citizen petition.
In a letter to the WHO back in July, he and his colleagues wrote: "Studies by the signatories and other scientists have demonstrated beyond any reasonable doubt that viruses are released during exhalation, talking, and coughing in microdroplets small enough to remain aloft in air and pose a risk of exposure at distances beyond 1–2 m from an infected individual."
The scientists have also gone direct to the public with their findings: They published a comprehensive Google doc with detailed answers to many people's frequently asked questions about how to protect themselves, addressing issues ranging from the best masks and air filters to how to deal with passing someone outdoors and much more.
It's worth noting that the CDC has now modified its COVID FAQ to include airborne transmission as a "less common way" for the virus to spread. This update took place after the CDC stated in September that it is "possible" the virus spreads via airborne transmission – only to reverse course and remove the language from its website several days later. The CDC's website now states that some viruses, including SARS-Cov-2, "may be able to infect people who are further than 6 feet away from the person who is infected or after that person has left the space."
Basset Allen notes that after the scientists' open letter, the WHO "added ventilation to public communications about how to prevent infection, but they haven't explained why."
When contacted, a WHO representative had no specific comment and shared its late March announcement as well as its latest guidelines on transmission. In part, its statement says, "Current evidence suggests that the main way the virus spreads is by respiratory droplets among people who are in close contact with each other. Aerosol transmission can occur in specific settings, particularly in indoor, crowded and inadequately ventilated spaces, where infected person(s) spend long periods of time with others, such as restaurants, choir practices, fitness classes, nightclubs, offices and/or places of worship. More studies are underway to better understand the conditions in which aerosol transmission is occurring outside of medical facilities where specific medical procedures, called aerosol-generating procedures, are conducted."
A forceful and clear message acknowledging the evidence could make it easier to standardize school and office ventilation, petitioners argue.
Aerosol scientist Jimenez was dismayed by the WHO's response.
"The first part is an error in my opinion," he says. "Current evidence suggests that the main way the virus spreads is inhalation of aerosols.…WHO is way behind, unfortunately.
"The second part is incomplete," Jimenez continues. "Aerosol transmission can happen in those indoor crowded low-ventilation spaces. But if aerosols can accumulate under those conditions and cause infection, they must be extremely infective in close proximity when talking, since they are much more concentrated there. Just like talking close to a smoker you would inhale much more smoke (which is an aerosol) than if you were in the same room, but let's say 10 or 15 feet away."
He adds, "The WHO and others are making the assumption that if this goes through the air, then everyone who is infected is putting a lot of virus into the air at all times, but we know that's wrong: People are infectious for a short period of time before and during their symptoms. In China, they have measured how much virus comes out of people, and they see that the emission is sporadic: The virus can come out in millions of viral [particles] per hour, but it doesn't happen all the time."
The petition's co-creator, Basset Allen, says that her life experience showed her the best way to make a change. "My involvement with this effort is entirely personal," she says. "I was first introduced to HIV treatment activism as a college student and what I learned about campaigning and power has been relevant in almost every other project I've worked on since then. HIV activism taught me that everyday people can win big, life-saving policy changes if they build expertise and work strategically to push decision makers."
The petition and its advocates argue that the WHO's mixed messaging is causing real harm. For instance, a forceful and clear message acknowledging the evidence could make it easier to standardize school and office ventilation, they argue. Anecdotally, some schools have refused to install HEPA filtration in their classrooms due to a lack of specific guidance from health agencies. (Note: The CDC now recommends improving central air filtration and considering the use of portable HEPA filters in classrooms.)
As the holidays approach, a clear and unified message from all influential health agencies would also help people understand why it is still important to wear masks while physical distancing, especially indoors.
"Personally, I cheered when I heard President-Elect Biden mention ventilation upgrades in schools during the first 10 minutes of his October town hall event, and again in the second debate," Basset Allen says. "Unfortunately, we're still more than two months away from the Biden administration taking over the U.S. COVID-19 response and we have to do absolutely everything we can right now to save as many lives as possible. Increasing awareness of airborne transmission and mitigation strategies can't wait. WHO can use its power to help close that gap, here and around the world."
Personalized nutrition apps could provide valuable data to people trying to eat healthier, though more research must be done to show effectiveness.
“We discovered that different foods spike people differently,” he says. “Some people spike to pasta, others to bread, others to bananas, and so on. It’s very personalized and our feeling was that building programs around these devices could be extremely powerful for better managing people’s glucose.”
Unbeknown to Snyder at the time, thousands of miles away, a group of Israeli scientists at the Weizmann Institute of Science were doing exactly the same experiments. In 2015, they published a landmark paper which used CGM to track the blood sugar levels of 800 people over several days, showing that the biological response to identical foods can vary wildly. Like Snyder, they theorized that giving people a greater understanding of their own glucose responses, so they spend more time in the normal range, may reduce the prevalence of type 2 diabetes.
The commercial potential of such apps is clear, but the underlying science continues to generate intriguing findings.
“At the moment 33 percent of the U.S. population is pre-diabetic, and 70 percent of those pre-diabetics will become diabetic,” says Snyder. “Those numbers are going up, so it’s pretty clear we need to do something about it.”
Fast forward to 2022,and both teams have converted their ideas into subscription-based dietary apps which use artificial intelligence to offer data-informed nutritional and lifestyle recommendations. Snyder’s spinoff, January AI, combines CGM information with heart rate, sleep, and activity data to advise on foods to avoid and the best times to exercise. DayTwo–a start-up which utilizes the findings of Weizmann Institute of Science–obtains microbiome information by sequencing stool samples, and combines this with blood glucose data to rate ‘good’ and ‘bad’ foods for a particular person.
“CGMs can be used to devise personalized diets,” says Eran Elinav, an immunology professor and microbiota researcher at the Weizmann Institute of Science in addition to serving as a scientific consultant for DayTwo. “However, this process can be cumbersome. Therefore, in our lab we created an algorithm, based on data acquired from a big cohort of people, which can accurately predict post-meal glucose responses on a personal basis.”
The commercial potential of such apps is clear. DayTwo, who market their product to corporate employers and health insurers rather than individual consumers, recently raised $37 million in funding. But the underlying science continues to generate intriguing findings.
Last year, Elinav and colleagues published a study on 225 individuals with pre-diabetes which found that they achieved better blood sugar control when they followed a personalized diet based on DayTwo’s recommendations, compared to a Mediterranean diet. The journal Cell just released a new paper from Snyder’s group which shows that different types of fibre benefit people in different ways.
“The idea is you hear different fibres are good for you,” says Snyder. “But if you look at fibres they’re all over the map—it’s like saying all animals are the same. The responses are very individual. For a lot of people [a type of fibre called] arabinoxylan clearly reduced cholesterol while the fibre inulin had no effect. But in some people, it was the complete opposite.”
Eight years ago, Stanford's Michael Snyder began studying how continuous glucose monitors could be used by patients to gain real-time updates on their blood sugar levels, transmitted directly to their phone.
The Snyder Lab, Stanford Medicine
Because of studies like these, interest in precision nutrition approaches has exploded in recent years. In January, the National Institutes of Health announced that they are spending $170 million on a five year, multi-center initiative which aims to develop algorithms based on a whole range of data sources from blood sugar to sleep, exercise, stress, microbiome and even genomic information which can help predict which diets are most suitable for a particular individual.
“There's so many different factors which influence what you put into your mouth but also what happens to different types of nutrients and how that ultimately affects your health, which means you can’t have a one-size-fits-all set of nutritional guidelines for everyone,” says Bruce Y. Lee, professor of health policy and management at the City University of New York Graduate School of Public Health.
With the falling costs of genomic sequencing, other precision nutrition clinical trials are choosing to look at whether our genomes alone can yield key information about what our diets should look like, an emerging field of research known as nutrigenomics.
The ASPIRE-DNA clinical trial at Imperial College London is aiming to see whether particular genetic variants can be used to classify individuals into two groups, those who are more glucose sensitive to fat and those who are more sensitive to carbohydrates. By following a tailored diet based on these sensitivities, the trial aims to see whether it can prevent people with pre-diabetes from developing the disease.
But while much hope is riding on these trials, even precision nutrition advocates caution that the field remains in the very earliest of stages. Lars-Oliver Klotz, professor of nutrigenomics at Friedrich-Schiller-University in Jena, Germany, says that while the overall goal is to identify means of avoiding nutrition-related diseases, genomic data alone is unlikely to be sufficient to prevent obesity and type 2 diabetes.
“Genome data is rather simple to acquire these days as sequencing techniques have dramatically advanced in recent years,” he says. “However, the predictive value of just genome sequencing is too low in the case of obesity and prediabetes.”
Others say that while genomic data can yield useful information in terms of how different people metabolize different types of fat and specific nutrients such as B vitamins, there is a need for more research before it can be utilized in an algorithm for making dietary recommendations.
“I think it’s a little early,” says Eileen Gibney, a professor at University College Dublin. “We’ve identified a limited number of gene-nutrient interactions so far, but we need more randomized control trials of people with different genetic profiles on the same diet, to see whether they respond differently, and if that can be explained by their genetic differences.”
Some start-ups have already come unstuck for promising too much, or pushing recommendations which are not based on scientifically rigorous trials. The world of precision nutrition apps was dubbed a ‘Wild West’ by some commentators after the founders of uBiome – a start-up which offered nutritional recommendations based on information obtained from sequencing stool samples –were charged with fraud last year. The weight-loss app Noom, which was valued at $3.7 billion in May 2021, has been criticized on Twitter by a number of users who claimed that its recommendations have led to them developed eating disorders.
With precision nutrition apps marketing their technology at healthy individuals, question marks have also been raised about the value which can be gained through non-diabetics monitoring their blood sugar through CGM. While some small studies have found that wearing a CGM can make overweight or obese individuals more motivated to exercise, there is still a lack of conclusive evidence showing that this translates to improved health.
However, independent researchers remain intrigued by the technology, and say that the wealth of data generated through such apps could be used to help further stratify the different types of people who become at risk of developing type 2 diabetes.
“CGM not only enables a longer sampling time for capturing glucose levels, but will also capture lifestyle factors,” says Robert Wagner, a diabetes researcher at University Hospital Düsseldorf. “It is probable that it can be used to identify many clusters of prediabetic metabolism and predict the risk of diabetes and its complications, but maybe also specific cardiometabolic risk constellations. However, we still don’t know which forms of diabetes can be prevented by such approaches and how feasible and long-lasting such self-feedback dietary modifications are.”
Snyder himself has now been wearing a CGM for eight years, and he credits the insights it provides with helping him to manage his own diabetes. “My CGM still gives me novel insights into what foods and behaviors affect my glucose levels,” he says.
He is now looking to run clinical trials with his group at Stanford to see whether following a precision nutrition approach based on CGM and microbiome data, combined with other health information, can be used to reverse signs of pre-diabetes. If it proves successful, January AI may look to incorporate microbiome data in future.
“Ultimately, what I want to do is be able take people’s poop samples, maybe a blood draw, and say, ‘Alright, based on these parameters, this is what I think is going to spike you,’ and then have a CGM to test that out,” he says. “Getting very predictive about this, so right from the get go, you can have people better manage their health and then use the glucose monitor to help follow that.”
Two students had an idea at a scrapyard. They went on to "upcycle" 80,000 airbags, 100,000 seatbelts and 28,000 belt buckles – the equivalent of 60 tons of car trash
Much to their surprise, their classmates responded with so much enthusiasm to their “trash bag” concept that it convinced the two innovators to keep going. Every semester, they improved the prototype further. With the help of YouTube videos, they taught themselves how to sew. Because modern electric sewing machines had a difficult time breaking through the tough nylon of the airbags, Goosses and Widmann went to a second-hand shop and purchased an ancient Singer from 1880 for 10 Euros. They dyed the first airbags in a saucepan in the garden outside of the apartment they shared.
“By the time we graduated, we had a presentable prototype and a business plan,” Goosses says.
Despite their progress, Goosses and Widmann are up against a problem that’s immense: Cars are notoriously difficult to recycle because many parts are considered toxic waste.
It’s an example of “upcycling,” when you spot a potential new use in something that’s been trashed, shelved or otherwise retired. The approach has received increasing attention and support from the U.S. Environmental Protection Agency and others to boost sustainability in all kinds of areas, from fashion (where even luxury brands like Balenciaga or Coach repurpose vintage clothing and bags) to architecture, where reusing wood, steel and bricks significantly reduces a building’s carbon footprint.
In addition to helping the planet, those who do it well can make a living from it. These days, Goosses and Widmann own a flourishing company: Airpaq. A crowdfunding campaign in 2017 yielded 70,000 Euros to get them started. Since then, they have upcycled 80,000 airbags, 100,000 seatbelts and 28,000 belt buckles – the equivalent of 60 tons of car trash.
For the successful upcycling, they received the 2021 German Design Award and, earlier this year, the renowned German Sustainability Award. The jurors evaluating the product commented that the startup “convinced us not only because of their uncompromising quality and functionality but also because of their ecological and ethical values….How well the startup translates upcycling and green fashion into an urban lifestyle brand is impressive.”
Despite their progress, Goosses and Widmann are up against a problem that’s immense: Cars are notoriously difficult to recycle because many parts are considered toxic waste. Therefore, up to 25% of vehicle scraps get shredded every year in Germany alone, the equivalent of over 501,000 tons. Because airbags and seatbelts are nearly indestructible, they are costly to recycle and almost always end up in landfills. Given that airbags and seatbelts save lives, they are subject to stringent security regulations, and manufacturers have a sky-high reject rate. “If a tiny filament protrudes somewhere, the manufacturer will throw out the entire output,” Widmann explains.
The nearly indestructible qualities that make this material very difficult to recycle render it an excellent resource for backpacks. “The material is so durable, you almost cannot tear it,” Goosses adds and demonstrates with a hard tug that even when the material already has a hole, it won’t rip it further. The material is also water repellent and extremely light.
The antique Singer is still in their Cologne headquarters but only as decoration. Their company with 12 employees is producing 500 backpacks and fanny packs every week in Romania, where the parts are professionally cut by laser, dyed and sewed. Airpaq still procures the belt buckles at scrapyards but they get most of the airbags directly from the reject pile of a nearby airbag producer. “We process the materials where they are produced,” Goosses explains. Only about 15 miles lie between one of Europe’s biggest airbag manufacturers and the Airpaq seamsters in Romania.
Co-founders Adrian Goosses and Michael Widmann demonstrate their company's equation: airbag plus seatbelt equals a backpack that's durable and eco-friendly.
Airpaq
The founders are aware that with price tags ranging from 100 to 160 Euro - a cost that reflects their intensive production process - Airpaq’s bags are hardly competitive. After all, anybody can buy a discount backpack for a fraction of the cost. So they recently added fanny packs for 30 Euro to their product line. Goosses and Widmann know they will need to lower their prices in the long run if they want to expand. Among other things, they didn’t pay themselves salaries during the first two years after founding the company.
Money-making isn’t their only objective. “Of course, it would be cheaper if we did what almost all textile producers do and move production to Asia,” Goosses says. That wasn’t an option for him. “Ship trash to Vietnam and let seamsters sew it together for cheap? No way, that would be anything but sustainable,” he says.
Michael Widmann’s family was already operating a textile production in Romania, mainly producing thin, elastic sports fashion. The family allowed Widmann and Goosses to produce their first professional prototypes there, but then the two youngsters had to buy their own machines, acquire the necessary knowhow, and hire their staff. They both moved to Romania for six months “to get to know the people behind the machines.” The founders emphasize that they pay fair wages, use eco-certified dyes and clean their own wastewater. “Normal production uses five to six liters of water per kilo material,” Widmann explains. “We only need a fraction because we massage the dye into the material by hand: 100 ml water for washing and dying per kilo.”
However, every time they return to the scrapyard, the abundance of trash sparks new ideas. “When you see how much material ends up there…” Widmann says, shaking his head without finishing the sentence. Goosses picks up the train of thought: “We want to make upcycling the new standard. You just have to be creative to get upcycling into the mainstream.”
And maybe they’ll return to their roots and finally find an idea for the tires after all. “One could turn the rubber into soles for comfortable shoes,” Widmann thinks out loud.