The Nose Knows: Dogs Are Being Trained to Detect the Coronavirus
Security workers walk with detection dogs in an airport terminal.
Asher is eccentric and inquisitive. He loves an audience, likes keeping busy, and howls to be let through doors. He is a six-year-old working Cocker Spaniel, who, with five other furry colleagues, has now been trained to sniff body odor samples from humans to detect COVID-19 infections.
As the Delta variant and other new versions of the SARS-CoV-2 virus emerge, public health agencies are once again recommending masking while employers contemplate mandatory vaccination. While PCR tests remain the "gold standard" of COVID-19 tests, they can take hours to flag infections. To accelerate the process, scientists are turning to a new testing tool: sniffer dogs.
At the London School of Hygiene and Tropical Medicine (LSHTM), researchers deployed Asher and five other trained dogs to test sock samples from 200 asymptomatic, infected individuals and 200 healthy individuals. In May, they published the findings of the yearlong study in a preprint, concluding that dogs could identify COVID-19 infections with a high degree of accuracy – they could correctly identify a COVID-positive sample up to 94% of the time and a negative sample up to 92% of the time. The paper has yet to be peer-reviewed.
"Dogs can screen lots of people very quickly – 300 people per dog per hour. This means they could be used in places like airports or public venues like stadiums and maybe even workplaces," says James Logan, who heads the Department of Disease Control at LSHTM, adding that canines can also detect variants of SARS-CoV-2. "We included samples from two variants and the dogs could still detect them."
Detection dogs have been one of the most reliable biosensors for identifying the odor of human disease. According to Gemma Butlin, a spokesperson of Medical Detection Dogs, the UK-based charity that trained canines for the LSHTM study, the olfactory capabilities of dogs have been deployed to detect malaria, Parkinson's disease, different types of cancers, as well as pseudomonas, a type of bacteria known to cause infections in blood, lungs, eyes, and other parts of the human body.
COVID-19 has a distinctive smell — a result of chemicals known as volatile organic compounds released by infected body cells, which give off an odor "fingerprint."
"It's estimated that the percentage of a dog's brain devoted to analyzing odors is 40 times larger than that of a human," says Butlin. "Humans have around 5 million scent receptors dedicated to smell. Dogs have 350 million and can detect odors at parts per trillion. To put this into context, a dog can detect a teaspoon of sugar in a million gallons of water: two Olympic-sized pools full."
According to LSHTM scientists, COVID-19 has a distinctive smell — a result of chemicals known as volatile organic compounds released by infected body cells, which give off an odor "fingerprint." Other studies, too, have revealed that the SARS-CoV-2 virus has a distinct olfactory signature, detectable in the urine, saliva, and sweat of infected individuals. Humans can't smell the disease in these fluids, but dogs can.
"Our research shows that the smell associated with COVID-19 is at least partly due to small and volatile chemicals that are produced by the virus growing in the body or the immune response to the virus or both," said Steve Lindsay, a public health entomologist at Durham University, whose team collaborated with LSHTM for the study. He added, "There is also a further possibility that dogs can actually smell the virus, which is incredible given how small viruses are."
In April this year, researchers from the University of Pennsylvania and collaborators published a similar study in the scientific journal PLOS One, revealing that detection dogs could successfully discriminate between urine samples of infected and uninfected individuals. The accuracy rate of canines in this study was 96%. Similarly, last December, French scientists found that dogs were 76-100% effective at identifying individuals with COVID-19 when presented with sweat samples.
Grandjean Dominique, a professor at France's National Veterinary School of Alfort, who led the French study, said that the researchers used two types of dogs — search and rescue dogs, as they can sniff sweat, and explosive detection dogs, because they're often used at airports to find bomb ingredients. Dogs may very well be as good as PCR tests, said Dominique, but the goal, he added, is not to replace these tests with canines.
In France, the government gave the green light to train hundreds of disease detection dogs and deploy them in airports. "They will act as mass pre-test, and only people who are positive will undergo a PCR test to check their level of infection and the kind of variant," says Dominique. He thinks the dogs will be able to decrease the amount of PCR testing and potentially save money.
Since the accuracy rate for bio-detection dogs is fairly high, scientists think they could prove to be a quick diagnosis and mass screening tool, especially at ports, airports, train stations, stadiums, and public gatherings. Countries like Finland, Thailand, UAE, Italy, Chile, India, Australia, Pakistan, Saudi Arabia, Switzerland, and Mexico are already training and deploying canines for COVID-19 detection. The dogs are trained to sniff the area around a person, and if they find the odor of COVID-19 they will sit or stand back from an individual as a signal that they've identified an infection.
While bio-detection dogs seem promising for cheap, large-volume screening, many of the studies that have been performed to date have been small and in controlled environments. The big question is whether this approach work on people in crowded airports, not just samples of shirts and socks in a lab.
"The next step is 'real world' testing where they [canines] are placed in airports to screen people and see how they perform," says Anna Durbin, professor of international health at the John Hopkins Bloomberg School of Public Health. "Testing in real airports with lots of passengers and competing scents will need to be done."
According to Butlin of Medical Detection Dogs, scalability could be a challenge. However, scientists don't intend to have a dog in every waiting room, detecting COVID-19 or other diseases, she said.
"Dogs are the most reliable bio sensors on the planet and they have proven time and time again that they can detect diseases as accurately, if not more so, than current technological diagnostics," said Butlin. "We are learning from them all the time and what their noses know will one day enable the creation an 'E-nose' that does the same job – imagine a day when your mobile phone can tell you that you are unwell."
How sharing, hearing, and remembering positive stories can help shape our brains for the better
Across cultures and through millennia, human beings have always told stories. Whether it’s a group of boy scouts around a campfire sharing ghost stories or the paleolithic Cro-Magnons etching pictures of bison on cave walls, researchers believe that storytelling has been universal to human beings since the development of language.
But storytelling was more than just a way for our ancestors to pass the time. Researchers believe that storytelling served an important evolutionary purpose, helping humans learn empathy, share important information (such as where predators were or what berries were safe to eat), as well as strengthen social bonds. Quite literally, storytelling has made it possible for the human race to survive.
Today, neuroscientists are discovering that storytelling is just as important now as it was millions of years ago. Particularly in sharing positive stories, humans can more easily form relational bonds, develop a more flexible perspective, and actually grow new brain circuitry that helps us survive. Here’s how.
How sharing stories positively impacts the brain
When human beings share stories, it increases the levels of certain neurochemicals in the brain, neuroscientists have found. In a 2021 study published in Proceedings of the National Academy of Sciences (PNAS), Swedish researchers found that simply hearing a story could make hospitalized children feel better, compared to other hospitalized children who played a riddle game for the same amount of time. In their research, children in the intensive care unit who heard stories for just 30 minutes had higher levels of oxytocin, a hormone that promotes positive feelings and is linked to relaxation, trust, social connectedness, and overall psychological stability. Furthermore, the same children showed lower levels of cortisol, a hormone associated with stress. Afterward, the group of children who heard stories tended to describe their hospital experiences more positively, and even reported lower levels of pain.
Annie Brewster, MD, knows the positive effect of storytelling from personal experience. An assistant professor at Harvard Medical School and the author of The Healing Power of Storytelling: Using Personal Narrative to Navigate Illness, Trauma, and Loss, Brewster started sharing her personal experience with chronic illness after being diagnosed with multiple sclerosis in 2001. In doing so, Brewster says it has enabled her to accept her diagnosis and integrate it into her identity. Brewster believes so much in the power of hearing and sharing stories that in 2013 she founded Health Story Collaborative, a forum for others to share their mental and physical health challenges.“I wanted to hear stories of people who had found ways to move forward in positive ways, in spite of health challenges,” Brewster said. In doing so, Brewster believes people with chronic conditions can “move closer to self-acceptance and self-love.”
While hearing and sharing positive stories has been shown to increase oxytocin and other “feel good” chemicals, simply remembering a positive story has an effect on our brains as well. Mark Hoelterhoff, PhD, a lecturer in clinical psychology at the University of Edinburgh, recalling and “savoring” a positive story, thought, or feedback “begins to create new brain circuitry—a new neural network that’s geared toward looking for the positive,” he says. Over time, other research shows, savoring positive stories or thoughts can literally change the shape of your brain, hard-wiring someone to see things in a more positive light.How stories can change your behavior
In 2009, Paul Zak, PhD, a neuroscientist and professor at Claremont Graduate University, set out to measure how storytelling can actually change human behavior for the better. In his study, Zak wanted to measure the behavioral effects of oxytocin, and did this by showing test subjects two short video clips designed to elicit an emotional response.
In the first video they showed the study participants, a father spoke to the camera about his two-year-old son, Ben, who had been diagnosed with terminal brain cancer. The father told the audience that he struggled to connect with and enjoy Ben, as Ben had only a few months left to live. In the end, the father finds the strength to stay emotionally connected to his son until he dies.
The second video clip, however, was much less emotional. In that clip, the same father and son are shown spending the day at the zoo. Ben is only suggested to have cancer (he is bald from chemotherapy and referred to as a ‘miracle’, but the cancer isn’t mentioned directly). The second story lacked the dramatic narrative arc of the first video.
Zak’s team took blood before and after the participants watched one of the two videos and found that the first story increased the viewers’ cortisol and oxytocin, suggesting that they felt distress over the boy’s diagnosis and empathy toward the boy and his father. The second narrative, however, didn’t increase oxytocin or cortisol at all.
But Zak took the experiment a step further. After the movie clips, his team gave the study participants a chance to share money with a stranger in the lab. The participants who had an increase in cortisol and oxytocin were more likely to donate money generously. The participants who had increased cortisol and oxytocin were also more likely to donate money to a charity that works with children who are ill. Zak also found that the amount of oxytocin that was released was correlated with how much money people felt comfortable giving—in other words, the more oxytocin that was released, the more generous they felt, and the more money they donated.
How storytelling strengthens our bond with others
Sharing, hearing, and remembering stories can be a powerful tool for social change–not only in the way it changes our brain and our behavior, but also because it can positively affect our relationships with other people
Emotional stimulation from telling stories, writes Zak, is the foundation for empathy, and empathy strengthens our relationships with other people. “By knowing someone’s story—where they come from, what they do, and who you might know in common—relationships with strangers are formed.”
But why are these relationships important for humanity? Because human beings can use storytelling to build empathy and form relationships, it enables them to “engage in the kinds of large-scale cooperation that builds massive bridges and sends humans into space,” says Zak.
Storytelling, Zak found, and the oxytocin release that follows, also makes people more sensitive to social cues. This sensitivity not only motivates us to form relationships, but also to engage with other people and offer help, particularly if the other person seems to need help.
But as Zak found in his experiments, the type of storytelling matters when it comes to affecting relationships. Where Zak found that storytelling with a dramatic arc helps release oxytocin and cortisol, enabling people to feel more empathic and generous, other researchers have found that sharing happy stories allows for greater closeness between individuals and speakers. A group of Chinese researchers found that, compared to emotionally-neutral stories, happy stories were more “emotionally contagious.” Test subjects who heard happy stories had greater activation in certain areas of their brains, experienced more significant, positive changes in their mood, and felt a greater sense of closeness between themselves and the speaker.
“This finding suggests that when individuals are happy, they become less self-focused and then feel more intimate with others,” the authors of the study wrote. “Therefore, sharing happiness could strengthen interpersonal bonding.” The researchers went on to say that this could lead to developing better social networks, receiving more social support, and leading more successful social lives.
Since the start of the COVID pandemic, social isolation, loneliness, and resulting mental health issues have only gotten worse. In light of this, it’s safe to say that hearing, sharing, and remembering stories isn’t just something we can do for entertainment. Storytelling has always been central to the human experience, and now more than ever it’s become something crucial for our survival.
Want to know how you can reap the benefits of hearing happy stories? Keep an eye out for Upworthy’s first book, GOOD PEOPLE: Stories from the Best of Humanity, published by National Geographic/Disney, available on September 3, 2024. GOOD PEOPLE is a much-needed trove of life-affirming stories told straight from the heart. Handpicked from Upworthy’s community, these 101 stories speak to the breadth, depth, and beauty of the human experience, reminding us we have a lot more in common than we realize.
A new type of cancer therapy is shrinking deadly brain tumors with just one treatment
MRI scans after a new kind of immunotherapy for brain cancer show remarkable progress in one patient just days after the first treatment.
Few cancers are deadlier than glioblastomas—aggressive and lethal tumors that originate in the brain or spinal cord. Five years after diagnosis, less than five percent of glioblastoma patients are still alive—and more often, glioblastoma patients live just 14 months on average after receiving a diagnosis.
But an ongoing clinical trial at Mass General Cancer Center is giving new hope to glioblastoma patients and their families. The trial, called INCIPIENT, is meant to evaluate the effects of a special type of immune cell, called CAR-T cells, on patients with recurrent glioblastoma.
How CAR-T cell therapy works
CAR-T cell therapy is a type of cancer treatment called immunotherapy, where doctors modify a patient’s own immune system specifically to find and destroy cancer cells. In CAR-T cell therapy, doctors extract the patient’s T-cells, which are immune system cells that help fight off disease—particularly cancer. These T-cells are harvested from the patient and then genetically modified in a lab to produce proteins on their surface called chimeric antigen receptors (thus becoming CAR-T cells), which makes them able to bind to a specific protein on the patient’s cancer cells. Once modified, these CAR-T cells are grown in the lab for several weeks so that they can multiply into an army of millions. When enough cells have been grown, these super-charged T-cells are infused back into the patient where they can then seek out cancer cells, bind to them, and destroy them. CAR-T cell therapies have been approved by the US Food and Drug Administration (FDA) to treat certain types of lymphomas and leukemias, as well as multiple myeloma, but haven’t been approved to treat glioblastomas—yet.
CAR-T cell therapies don’t always work against solid tumors, such as glioblastomas. Because solid tumors contain different kinds of cancer cells, some cells can evade the immune system’s detection even after CAR-T cell therapy, according to a press release from Massachusetts General Hospital. For the INCIPIENT trial, researchers modified the CAR-T cells even further in hopes of making them more effective against solid tumors. These second-generation CAR-T cells (called CARv3-TEAM-E T cells) contain special antibodies that attack EFGR, a protein expressed in the majority of glioblastoma tumors. Unlike other CAR-T cell therapies, these particular CAR-T cells were designed to be directly injected into the patient’s brain.
The INCIPIENT trial results
The INCIPIENT trial involved three patients who were enrolled in the study between March and July 2023. All three patients—a 72-year-old man, a 74-year-old man, and a 57-year-old woman—were treated with chemo and radiation and enrolled in the trial with CAR-T cells after their glioblastoma tumors came back.
The results, which were published earlier this year in the New England Journal of Medicine (NEJM), were called “rapid” and “dramatic” by doctors involved in the trial. After just a single infusion of the CAR-T cells, each patient experienced a significant reduction in their tumor sizes. Just two days after receiving the infusion, the glioblastoma tumor of the 72-year-old man decreased by nearly twenty percent. Just two months later the tumor had shrunk by an astonishing 60 percent, and the change was maintained for more than six months. The most dramatic result was in the 57-year-old female patient, whose tumor shrank nearly completely after just one infusion of the CAR-T cells.
The results of the INCIPIENT trial were unexpected and astonishing—but unfortunately, they were also temporary. For all three patients, the tumors eventually began to grow back regardless of the CAR-T cell infusions. According to the press release from MGH, the medical team is now considering treating each patient with multiple infusions or prefacing each treatment with chemotherapy to prolong the response.
While there is still “more to do,” says co-author of the study neuro-oncologist Dr. Elizabeth Gerstner, the results are still promising. If nothing else, these second-generation CAR-T cell infusions may someday be able to give patients more time than traditional treatments would allow.
“These results are exciting but they are also just the beginning,” says Dr. Marcela Maus, a doctor and professor of medicine at Mass General who was involved in the clinical trial. “They tell us that we are on the right track in pursuing a therapy that has the potential to change the outlook for this intractable disease.”