Daisy wouldn't leave Claire Guest alone. Instead of joining Guest's other dogs for a run in the park, the golden retriever with the soulful eyes kept nudging Guest's chest, and stared at her intently, somehow hoping she'd get the message.
"I was incredibly lucky to be told by Daisy."
When Guest got home, she detected a tiny lump in one of her breasts. She dismissed it, but her sister, who is a family doctor, insisted she get it checked out.
That saved her life. A series of tests, including a biopsy and a mammogram, revealed the cyst was benign. But doctors discovered a tumor hidden deep inside her chest wall, an insidious malignancy that normally isn't detected until the cancer has rampaged out of control throughout the body. "My prognosis would have been very poor," says Guest, who is an animal behavioralist. "I was incredibly lucky to be told by Daisy."
Ironically, at the time, Guest was training hearing dogs for the deaf—alerting them to doorbells or phones--for a charitable foundation. But she had been working on a side project to harness dogs' exquisitely sensitive sense of smell to spot cancer at its earliest and most treatable stages. When Guest was diagnosed with cancer two decades ago, however, the use of dogs to detect diseases was in its infancy and scientific evidence was largely anecdotal.
In the years since, Guest and the British charitable foundation she co-founded with Dr. John Church in 2008, Medical Detection Dogs (MDD), has shown that dogs can be trained to detect odors that predict a looming medical crisis hours in advance, in the case of diabetes or epilepsy, as well as the presence of cancers.
In a proof of principle study published in the BMJ in 2004, they showed dogs had better than a 40 percent success rate in identifying bladder cancer, which was significantly better than random chance (14 percent). Subsequent research indicated dogs can detect odors down to parts per trillion, which is the equivalent of sniffing out a teaspoon of sugar in two Olympic size swimming pools (a million gallons).
American scientists are devising artificial noses that mimic dogs' sense of smell, so these potentially life-saving diagnostic tools are widely available.
But the problem is "dogs can't be scaled up"—it costs upwards of $25,000 to train them—"and you can't keep a trained dog in every oncology practice," says Guest.
The good news is that the pivotal 2004 BMJ paper caught the attention of two American scientists—Andreas Mershin, a physicist at MIT, and Wen-Yee Yee, a chemistry professor at The University of Texas at El Paso. They have joined Guest's quest to leverage canines' highly attuned olfactory systems and devise artificial noses that mimic dogs' sense of smell, so these potentially life-saving diagnostic tools are widely available.
"What we do know is that this is real," says Guest. "Anything that can improve diagnosis of cancer is something we ought to know about."
Dogs have routinely been used for centuries as trackers for hunting and more recently, for ferreting out bombs and bodies. Dogs like Daisy, who went on to become a star performer in Guest's pack of highly trained cancer detecting canines before her death in 2018, have shared a special bond with their human companions for thousands of years. But their vastly superior olfaction is the result of simple anatomy.
Humans possess about six million olfactory receptors—the antenna-like structures inside cell membranes in our nose that latch on to the molecules in the air when we inhale. In contrast, dogs have about 300 million of them and the brain region that analyzes smells is, proportionally, about 40 times greater than ours.
Research indicates that cancerous cells interfere with normal metabolic processes, prompting them to produce volatile organic compounds (VOCs), which enter the blood stream and are either exhaled in our breath or excreted in urine. Dogs can identify these VOCs in urine samples at the tiniest concentrations, 0.001 parts per million, and can be trained to identify the specific "odor fingerprint" of different cancers, although teaching them how to distinguish these signals from background odors is far more complicated than training them to detect drugs or explosives.
For the past fifteen years, Andreas Mershin of MIT has been grappling with this complexity in his quest to devise an artificial nose, which he calls the Nano-Nose, first as a military tool to spot land mines and IEDS, and more recently as a cancer detection tool that can be used in doctors' offices. The ultimate goal is to create an easy-to-use olfaction system powered by artificial intelligence that can fit inside of smartphones and can replicate dogs' ability to sniff out early signs of prostate cancer, which could eliminate a lot of painful and costly biopsies.
Andreas Mershin works on his artificial nose.
Trained canines have a better than 90 percent accuracy in spotting prostate cancer, which is normally difficult to detect. The current diagnostic, the prostate specific antigen test, which measures levels of certain immune system cells associated with prostate cancer, has about as much accuracy "as a coin toss," according to the scientist who discovered PSA. These false positives can lead to unnecessary and horrifically invasive biopsies to retrieve tissue samples.
So far, Mershin's prototype device has the same sensitivity as the dogs—and can detect odors at parts per trillion—but it still can't distinguish that cancer smell in individual human patients the way a dog can. "What we're trying to understand from the dogs is how they look at the data they are collecting so we can copy it," says Mershin. "We still have to make it intelligent enough to know what it is looking at—what we are lacking is artificial dog intelligence."
The intricate parts of the artificial nose are designed to fit inside a smartphone.
At UT El Paso, Wen-Yee Lee and her research team has used the canine olfactory system as a model for a new screening test for prostate cancer, which has a 92 percent accuracy in tests of urine samples and could be eventually developed as a kit similar to the home pregnancy test. "If dogs can do it, we can do it better," says Lee, whose husband was diagnosed with prostate cancer in 2005.
The UT scientists used samples from about 150 patients, and looked at about 9,000 compounds before they were able to zero in on the key VOCs that are released by prostate cancers—"it was like finding a needle in the haystack," says Lee. But a more reliable test that can also distinguish which cancers are more aggressive could help patients decide their best treatment options and avoid invasive procedures that can render them incontinent and impotent.
"This is much more accurate than the PSA—we were able to see a very distinct difference between people with prostate cancer and those without cancer," says Lee, who has been sharing her research with Guest and hopes to have the test on the market within the next few years.
In the meantime, Guest's foundation has drawn the approving attention of royal animal lovers: Camilla, the Duchess of Cornwall, is a patron, which opened up the charitable floodgates and helped legitimize MDD in the scientific community. Even Camilla's mother-in-law, Queen Elizabeth, has had a demonstration of these canny canines' unique abilities.
Claire Guest, and two of MDDs medical detection dogs, Jodie and Nimbus, meet with queen Elizabeth.
"She actually held one of my [artificial] noses in her hand and asked really good questions, including things we hadn't thought of, like the range of how far away a dog can pick up the scent or if this can be used to screen for malaria," says Mershin. "I was floored by this curious 93-year-old lady. Half of humanity's deaths are from chronic diseases and what the dogs are showing is a whole new way of understanding holistic diseases of the system."
On the morning of April 12, 1955, newsrooms across the United States inked headlines onto newsprint: the Salk Polio vaccine was "safe, effective, and potent." This was long-awaited news. Americans had limped through decades of fear, unaware of what caused polio or how to cure it, faced with the disease's terrifying, visible power to paralyze and kill, particularly children.
The announcement of the polio vaccine was celebrated with noisy jubilation: church bells rang, factory whistles sounded, people wept in the streets. Within weeks, mass inoculation began as the nation put its faith in a vaccine that would end polio.
Today, most of us are blissfully ignorant of child polio deaths, making it easier to believe that we have not personally benefited from the development of vaccines. According to Dr. Steven Pinker, cognitive psychologist and author of the bestselling book Enlightenment Now, we've become blasé to the gifts of science. "The default expectation is not that disease is part of life and science is a godsend, but that health is the default, and any disease is some outrage," he says.
The Rise and Fall of Public Trust<p>When the polio vaccine was released in 1955, "we were nearing an all-time high point in public trust," says Matt Baum, Harvard Kennedy School professor and lead author of <a href="http://www.kateto.net/covid19/COVID19%20CONSORTIUM%20REPORT%2013%20TRUST%20SEP%202020.pdf" target="_blank" rel="noopener noreferrer"><u>several</u></a> <a href="https://shorensteincenter.org/wp-content/uploads/2020/09/COVID19-CONSORTIUM-REPORT-14-MISINFO-SEP-2020.pdf" target="_blank" rel="noopener noreferrer"><u>reports</u></a> measuring public trust and vaccine confidence. Baum explains that the U.S. was experiencing a post-war boom following the Allied triumph in WWII, a popular Roosevelt presidency, and the rapid innovation that elevated the country to an international superpower.</p><p> The 1950s witnessed the emergence of nuclear technology, a space program, and unprecedented medical breakthroughs, adds Emily Brunson, Texas State University anthropologist and co-chair of the Working Group on Readying Populations for COVID-19 Vaccine. "Antibiotics were a game changer," she states. While before, people got sick with pneumonia for a month, suddenly they had access to pills that accelerated recovery. </p><p>During this period, science seemed to hold all the answers; people embraced the idea that we could "come to know the world with an absolute truth," Brunson explains. Doctors were portrayed as unquestioned gods, so Americans were primed to trust experts who told them the polio vaccine was safe. </p>
The Shift in How We Consume Information<p>In the 1950s, the media created an informational consensus. The fundamental ideas the public consumed about the state of the world were unified. "People argued about the best solutions, but didn't fundamentally disagree on the factual baseline," says Baum. Indeed, the messaging around the polio vaccine was centralized and consistent, led by President Roosevelt's successful <a href="https://files.eric.ed.gov/fulltext/EJ978264.pdf" target="_blank" rel="noopener noreferrer"><u>March of Dimes crusade</u></a>. People of lower socioeconomic status with limited access to this information were <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1551508/?page=3" target="_blank" rel="noopener noreferrer"><u>less likely to have confidence</u></a> in the vaccine, but most people consumed <a href="https://www.c-span.org/video/?506891-1/a-special-report-polio" target="_blank" rel="noopener noreferrer"><u>media that assured them</u></a> of the vaccine's safety and <a href="https://www.cbsnews.com/news/the-salk-polio-vaccine-greatest-public-health-experiment-in-history/" target="_blank" rel="noopener noreferrer"><u>mobilized them</u></a> to receive it. </p><p>Today, the information we consume is no longer centralized—in fact, just the opposite. "When you take that away, it's hard for people to know what to trust and what not to trust," Baum explains. We've witnessed an increase in polarization and the technology that makes it easier to give people what they want to hear, reinforcing the human tendencies to vilify the other side and reinforce our preexisting ideas. When information is engineered to further an agenda, each choice and risk calculation made while navigating the COVID-19 pandemic <a href="https://www.nytimes.com/2020/12/19/opinion/sunday/coronavirus-science.html?referringSource=articleShare" target="_blank" rel="noopener noreferrer"><u>is deeply politicized</u></a>. </p><p>This polarization maps onto a rise in socioeconomic inequality and economic uncertainty. These factors, associated with a sense of lost control, prime people to embrace misinformation, explains Baum, especially when the situation is difficult to comprehend. "The beauty of conspiratorial thinking is that it provides answers to all these questions," he says. Today's insidious fragmentation of news media accelerates the circulation of mis- and disinformation, reaching more people faster, regardless of veracity or motivation. In the case of vaccines, skepticism around their origin, safety, and motivation is intensified. </p><p>Alongside the rise in polarization, Pinker says "the emotional tone of the news has gone downward since the 1940s, and journalists consider it a professional responsibility to cover the negative." Relentless focus on everything that goes wrong further erodes public trust and paints a picture of the world getting worse. "Life saved is not a news story," says Pinker, but perhaps it should be, he continues. "If people were more aware of how much better life was generally, they might be more receptive to improvements that will continue to make life better. These improvements don't happen by themselves."</p>
The Future Depends on Vaccine Confidence<p>So far, the U.S. has been unable to mitigate the catastrophic effects of the pandemic through social distancing, testing, and contact tracing. President Trump has <a href="https://www.washingtonpost.com/politics/bob-woodward-rage-book-trump/2020/09/09/0368fe3c-efd2-11ea-b4bc-3a2098fc73d4_story.html" target="_blank" rel="noopener noreferrer"><u>downplayed the effects and threat of the virus</u></a>, <a href="https://www.washingtonpost.com/outlook/2020/07/14/cdc-directors-trump-politics/" target="_blank" rel="noopener noreferrer"><u>censored experts and scientists</u></a>, <a href="https://www.theatlantic.com/science/archive/2020/06/america-giving-up-on-pandemic/612796/" target="_blank" rel="noopener noreferrer"><u>given up on containing the spread</u></a>, and <a href="https://www.nytimes.com/2020/09/16/world/covid-coronavirus.html" target="_blank" rel="noopener noreferrer"><u>mobilized his base to protest masks</u></a>. The Trump Administration failed to devise a national plan, so our national plan has defaulted to hoping for the <a href="https://www.politico.com/news/2020/08/26/nation-of-miracles-pence-coronavirus-vaccine-rnc-402949" target="_blank" rel="noopener noreferrer"><u>"miracle" of a vaccine</u></a>. And they are "something of a miracle," Pinker says, describing vaccines as "the most benevolent invention in the history of our species." In record-breaking time, three vaccines have arrived. But their impact will be weakened unless we achieve mass vaccination. As Brunson notes, "The technology isn't the fix; it's people taking the technology."</p><p> Significant challenges remain, including facilitating widespread access and supporting on-the-ground efforts to allay concerns and build trust with <a href="https://www.newyorker.com/news/daily-comment/african-american-resistance-to-the-covid-19-vaccine-reflects-a-broader-problem" target="_blank" rel="noopener noreferrer"><u>specific populations with historic reasons for distrust</u></a>, says Brunson. Baum predicts continuing delays as well as deaths from other causes that will be linked to the vaccine. </p><p> Still, there's every reason for hope. The new administration "has its eyes wide open to these challenges. These are the kind of problems that are amenable to policy solutions if we have the will," Baum says. He forecasts widespread vaccination by late summer and a bounce back from the economic damage, a "Good News Story" that will bolster vaccine acceptance in the future. And Pinker reminds us that science, medicine, and public health have greatly extended our lives in the last few decades, a trend that can only continue if we're willing to roll up our sleeves. </p>
Imagine this scenario: you get an annoying cough and a bit of a fever. When you wake up the next morning you lose your sense of taste and smell. That sounds familiar, so you head to a doctor's office for a Covid test, which comes back positive.
Your next step? An anti-Covid nasal spray of course, a "trickster drug" that will clear the once-dangerous and deadly virus out of the body. The drug works by tricking the coronavirus with decoy receptors that appear to be just like those on the surface of our own cells. The virus latches onto the drug's molecules "thinking" it is breaking into human cells, but instead it flushes out of your system before it can cause any serious damage.
This may sounds like science fiction, but several research groups are already working on such trickster coronavirus drugs, with some candidates close to clinical trials and possibly even becoming available late this year. The teams began working on them when the pandemic arrived, and continued in lockdown.
Biochemist David Baker, pictured in his lab at the University of Washington.