Given the large number of mutations found in the SARS-CoV-2 Omicron variant, experts in South Africa speculate it likely evolved in someone with a compromised immune system
As the SARS-CoV-2 Omicron variant spreads around the United States and the rest of the world, infectious disease experts in South Africa have been investigating how the variant developed so many mutations. One hypothesis is that it evolved over time in the body of an immunosuppressed person, such as a cancer patient, transplant recipient, or someone with uncontrolled human immunodeficiency virus infection (HIV).
One interesting facet in the story of how the Omicron variant was being tracked as it emerged in South Africa is the role of several medical laboratories in the country that reported genetic sequences associated with Omicron. This allowed researchers in South Africa to more quickly identify the growing range of mutations found in different samples of the Omicron virus.
“Normally your immune system would kick a virus out fairly quickly, if fully functional,” Linda-Gail Bekker, PhD, of the Desmond Tutu Health Foundation (formerly the Desmond Tutu HIV Foundation) in Cape Town, South Africa, told the BBC.
“In someone where immunity is suppressed, then we see virus persisting,” she added. “And it doesn’t just sit around, it replicates. And as it replicates it undergoes potential mutations. And in somebody where immunity is suppressed that virus may be able to continue for many months—mutating as it goes.”
Multiple factors can suppress the immune system, experts say, but some are pointing to HIV as a possible culprit given the likelihood that the variant emerged in sub-Saharan Africa, which has a high population of people living with HIV.
Li “was among the first to detail extensive coronavirus mutations in an immunosuppressed patient,” the LA Times reported. “Under attack by HIV, their T cells are not providing vital support that the immune system’s B cells need to clear an infection.”
Linda-Gail Bekker, PhD (above), of the Desmond Tutu Health Foundation cautions that these findings should not further stigmatize people living with HIV. “It’s important to stress that people who are on anti-retroviral medication—that does restore their immunity,” she told the BBC. (Photo copyright: Test Positive Aware Network.)
Omicron Spreads Rapidly in the US
Genomics surveillance Data from the CDC’s SARS-CoV-2 Tracking system indicates that on Dec. 11, 2021, Omicron accounted for about 7% of the SARS-CoV-2 variants in circulation, the agency reported. But by Dec. 25, the number had jumped to nearly 60%. The data is based on sequencing of SARS-CoV-2 by the agency as well as commercial clinical laboratories and academic laboratories.
Experts have pointed to several likely factors behind the variant’s high rate of transmission. The biggest factor, NPR reported, appears to be the large number of mutations on the spike protein, which the virus uses to attach to human cells. This gives the virus an advantage in evading the body’s immune system, even in people who have been vaccinated.
“The playing field for the virus right now is quite different than it was in the early days,” Joshua Schiffer, MD, of the Fred Hutchinson Cancer Research Center, told NPR. “The majority of variants we’ve seen to date couldn’t survive in this immune environment.”
One study from Norway cited by NPR suggests that Omicron has a shorter incubation period than other variants, which would increase the transmission rate. And researchers have found that it multiplies more rapidly than the Delta variant in the upper respiratory tract, which could facilitate spread when people exhale.
Using Genomics Testing to Determine How Omicron Evolved
But how did the Omicron variant accumulate so many mutations? In a story for The Atlantic, virologist Jesse Bloom, PhD, Professor, Basic Sciences Division, at the Fred Hutchinson Cancer Research Center in Seattle, described Omicron as “a huge jump in evolution,” one that researchers expected to happen “over the span of four or five years.”
Hence the speculation that it evolved in an immunosuppressed person, perhaps due to HIV, though that’s not the only theory. Another is “that the virus infected animals of some kind, acquired lots of mutations as it spread among them, and then jumped back to people—a phenomenon known as reverse zoonosis,” New Scientist reported.
Still, experts are pointing to emergence in someone with a weakened immune system as the most likely cause. One of them, the L.A. Times reported, is Tulio de Oliveira, PhD, Affiliate Professor in the Department of Global Health at the University of Washington. Oliveira leads the Centre for Epidemic Response and Innovation at Stellenbosch University in South Africa, as well as the nation’s Network for Genomic Surveillance.
The Network for Genomic Surveillance, he told The New Yorker, consists of multiple facilities around the country. Team members noticed what he described as a “small uptick” in COVID cases in Gauteng, so on Nov. 19 they decided to step up genomic surveillance in the province. One private clinical laboratory in the network submitted “six genomes of a very mutated virus,” he said. “And, when we looked at the genomes, we got quite worried because they discovered a failure of one of the probes in the PCR testing.”
Looking at national data, the scientists saw that the same failure was on the rise in PCR (Polymerase chain reaction) tests, prompting a request for samples from other medical laboratories. “We got over a hundred samples from over thirty clinics in Gauteng, and we started genotyping, and we analyzed the mutation of the virus,” he told The New Yorker. “We linked all the data with the PCR dropout, the increase of cases in South Africa and of the positivity rate, and then we began to see it might be a very suddenly emerging variant.”
Oliveira’s team first reported the emergence of the new variant to the World Health Organization, on Nov. 24. Two days later, the WHO issued a statement that named the newly classified Omicron variant (B.1.1.529) a “SARS-CoV-2 Variant of Concern.”
Microbiologists and clinical laboratory specialists in the US should keep close watch on Omicron research coming out of South Africa. Fortunately, scientists today have tools to understand the genetic makeup of viruses that did not exist at the time of SARS 2003, Swine flu 2008/9, MERS 2013.
Although there are healthcare providers who see the potential in microbiome testing, many clinical laboratories are not yet ready to embrace microbiome-based testing
In an unlikely string of events, no less than Nordstrom, the national department store chain, announced in September that it would offer microbiome-based test claimed to “check gut health.” Apparently, its customers were interested in this clinical laboratory test, as the Nordstrom website currently indicates that the “Health Intelligence Test Kit by Viome” is already sold out!
What does it say about consumer interest in clinical laboratory self-testing that Nordstrom has decided to offer at-home microbiome tests to its store customers? Can it be assumed that Nordstrom conducted enough marketing surveys of its customers to determine: a) that they were interested in microbiome testing; and b) they would buy enough microbiome tests that Nordstrom would benefit financially from either the mark-up on the tests or from the derived goodwill for meeting customer expectations?
Whatever the motivation, the retail giant recently announced it had partnered with Viome Life Sciences to sell Viome’s microbiome testing kits to its customers online, and in 2022, at some Nordstrom retail locations. These tests are centered around helping consumers understand the relationship between their microbiome and nutrition.
Pathologists and clinical laboratories will want to track Nordstrom’s success or failure in selling microbiome-based assays to its consumers. Microbiomics is in its infancy and remains a very unsettled area of diagnostics. Similarly, Viome, a self-described precision health and wellness company that conducts mRNA analysis at scale, will need to demonstrate that its strategy of developing precision medicine diagnostics and therapeutics based on the human microbiome has clinical relevance.
Helping Consumers with ‘Precision Nutrition’
In a September news release, Viome founder and CEO Naveen Jain, a serial entrepreneur, said, “Both Viome and Nordstrom believe that true health and beauty start from within. There is no such thing as a universal healthy food or healthy supplement. What is right for one person can be wrong for someone else, especially when it comes to nutrition which is key to human longevity and vitality. Precision nutrition is the future!”
“Precision medicine seeks to improve the personalized treatment of diseases, and precision nutrition is specific to dietary intake. Both develop interventions to prevent or treat chronic diseases based on a person’s unique characteristics like DNA, race, gender, health history, and lifestyle habits. Both aim to provide safer and more effective ways to prevent and treat disease by providing more accurate and targeted strategies.
“Precision nutrition assumes that each person may have a different response to specific foods and nutrients, so that the best diet for one individual may look very different than the best diet for another.
“Precision nutrition also considers the microbiome, trillions of bacteria in our bodies that play a key role in various daily internal operations. What types and how much bacteria we have are unique to each individual. Our diets can determine which types of bacteria live in our digestive tracts, and according to precision nutrition the reverse is also true: the types of bacteria we house might determine how we break down certain foods and what types of foods are most beneficial for our bodies.”
Medical Laboratory Testing, not Guessing
Viome Life Sciences is a microbiome and RNA analysis company based in Bellevue, Wash. The test kit that Nordstrom is selling is called the Health Intelligence Test. It is an at-home mRNA test that can provide users with some insights regarding their health. Consumers use the kit to collect blood and fecal samples, then return those samples to Viome for testing.
In a press release announcing its collaboration with Nordstrom, Viome said, “In a world overwhelmed by information relating to diet and supplement advice, Viome believes in testing, not guessing and empowering its users with actionable insights. To date, Viome has helped over 250,000 individuals improve their health through precision nutrition powered by microbial and human gene expression insights.”
Nordstrom began offering Viome’s Health Intelligence Test kit for $199 on its website starting in September. As of this writing and noted above, the kits are sold out. Nordstrom plans to stock the kit in select stores starting in 2022.
Viome’s Health Intelligence Test kit (above) looks at the microbiome to determine gut health, cellular health, healthy aging, immune health, and stress responses. Test results offer consumers personalized nutritional suggestions and recommendations for supplements, probiotics, and prebiotics based on an individual’s biology. Test are performed by Viome’s own clinical laboratories and results sent directly to Nordstrom’s customers. (Photo copyright: Viome Life Sciences.)
Individuals who purchase the test submit blood and stool samples to Viome’s lab which performs an analysis of gene activity patterns in the user’s cells and microbiome. Viome provides the results to consumers within two to three weeks.
“This partnership is a giant step towards making our technology more accessible, so people can understand what’s right for their unique body,” Jain said in the news release. “We are inspired each day by the incredible changes our customers are seeing in their health including improvements in digestion, weight, stress, ability to focus, and more.”
According to the news release, Viome conducted blind studies earlier this year that revealed significant successes based on their precision nutritional approach to wellness. Study participants, Viome claims, improved their outcomes to four diseases through nutrition:
Is Microbiome Diagnostics Testing Ready for Clinical Use?
Microbiomics is a relatively new field of diagnostics research. Much more research and testing will be needed to prove its clinical value and efficacy in healthcare diagnostics. Nevertheless, companies are offering microbiomics testing to consumers and that has some healthcare providers concerned.
In the GeekWire article, David Suskind, MD, a gastroenterologist at Seattle Children’s Hospital and Professor of Pediatrics at the University of Washington, described Viome’s study methodology as “questionable,” adding, “I think this is a very interesting and exciting space and I do think there are definite potential implications, down the road. [However] we are not there in terms of looking at microbiome and making broad recommendation for individuals, as of yet.”
Will at-home clinical laboratory testing kits that analyze an individual’s microbiome someday provide data that help people lead healthier lives and ward off diseases? That’s Jain’s prediction.
In an article published in Well+Good, Jain said, “COVID-19 has, of course, been such a dark time, but one positive that did come from it is that more people are taking control of their own health. I really believe that the future of healthcare will be delivered not at the hospital, but at home.”
If this collaboration between Nordstrom and Viome proves successful, similar partnerships between at-home diagnostics developers and established retail chains may become even more common. And that should be on the radars of pathologists and clinical laboratories.
CDC advises clinical laboratories and microbiologists encountering C. auris to follow their own protocols before adopting federal agency guidelines
In July, the Centers for Disease Control and Prevention (CDC) warned healthcare facilities and clinical laboratories to be on the alert for Candida auris (C. auris) infections in their patients. An outbreak of the drug resistant and potentially deadly fungus had appeared in two Dallas hospitals and a Washington D.C. nursing home.
Since those outbreaks, researchers have studied with urgency the “superbug’s” emergence in various types of healthcare facilities around the nation, not just hospitals. Their goal was to discover how it was successfully identified and contained.
“Seeing what was happening in New York, New Jersey, and Illinois [was] pretty alarming for a lot of the health officials in California [who] know that LTACHs are high-risk facilities because they take care of [very] sick people. Some of those people are there for a very long time,” the study’s lead author Ellora Karmarkar, MD, MSc, told Medscape. Karmarkar is an infectious disease fellow with the University of Washington and formerly an epidemic intelligence service officer with the CDC.
“One of the challenges was that people were so focused on COVID that they forgot about the MDROs (multi-drug resistant organisms] … Some of the things that we recommend to help control Candida auris are also excellent practices for every other organism including COVID care,” she added.
According to Medscape, “The OCHD researchers screened LTACH and vSNF patients with composite cultures from the axilla-groin or nasal swabs. Screening was undertaken because 5%–10% of colonized patients later develop invasive infections, and 30%–60% die.
Medscape also reported that the first bloodstream infection was detected in May 2019, and that, according to the Annals of Internal Medicine study, as of January 1, 2020, of 182 patients:
22 (12%) died within 30 days of C. auris identification,
“This is really the first time we’ve seen clustering of resistance in which patients seemed to be getting the infections from each other,” Meghan Lyman, MD, Medical Officer in the Mycotic Diseases Branch of the CDC, told Fox News.
The graphic above illustrates how Candida auris is “spanning the globe,” The New York Times reported. Clinical laboratories that encounter this potentially deadly fungus are advised to contact the CDC immediately for guidance and to take proactive steps to prepare for the “superbug’s” arrival. (Graphic copyright: The Scottish Sun.)
Be More Proactive than Reactive in Identifying C. Auris, CDC Says
C. auris is a type of yeast infection that can enter the bloodstream, spread throughout the body, and cause serious complications. People who appear to have the highest risk of contracting the infection are those:
Who have had a lengthy stay in a healthcare facility,
Individuals connected to a central venous catheter or other medical tubes, such as breathing or feeding tubes, or
Have previously received antibiotics or antifungal medications.
It tends to be resistant to the antifungal drugs that are commonly used to treat Candida infections.
It can be difficult to identify via standard laboratory testing and is easily misidentified in labs without specific technology.
It can quickly lead to outbreaks in healthcare settings.
“With all this spread that we’ve been seeing across the country we’re really encouraging health departments and facilities to be more proactive instead of reactive to identifying Candida auris in general,” Lyman told STAT. “Because we’ve found that controlling the situation and containing spread is really easiest when it’s identified early before there’s widespread transmission.”
There continues to be concerns over this highly drug-resistant infection among hospital physicians and medical laboratories. “Acute care hospitals really ought to be moving toward doing species identification of Candida from nonsterile sites if they really want to have a better chance of detecting this early,” Dan Diekema, MD (above), an epidemiologist and clinical microbiologist at the University of Iowa, told Medscape. (Photo copyright: University of Iowa.)
Candia Auris versus Other Candida Infections
C. auris can cause dangerous infections in the bloodstream and spread to the central nervous system, kidneys, liver, spleen, bones, muscles, and joints. It spreads mostly in long-term healthcare facilities among patients with other medical conditions.
The symptoms of having a Candida auris infection include:
Fever
Chills
Pain
Redness and swelling
Fluid drainage (if an incision or wound is present)
General feeling of tiredness and malaise
C. auris infections are typically diagnosed via cultures of blood or other bodily fluids, but they are difficult to distinguish from more common types of Candida infections, and special clinical laboratory tests are needed to definitively diagnose C. auris.
Whole-genome Sequencing of C. Auris and Drug Resistance
The CDC conducted whole-genome sequencing of C. auris specimens gathered in Asia, Africa, and South America and discovered four different strains of the potentially life-threatening Candida species. All four detected strains have been found in the United States.
There are only three classes of antifungal drugs used to treat Candida auris infections:
However, 85% of the infections in the US have proven to be resistant to azoles and 38% are resistant to polyenes. Patients respond well to echinocandins, but more effective therapies are needed especially as some isolates may become resistant while a patient is on drug therapy, STAT reported.
“Even while it might be susceptible upfront, after a week or two of therapy, we may find that the patient has an infection now caused by an isolate of the same Candida auris that has become resistant to the echinocandins and we are really left with nothing else,” Jeffrey Rybak, PhD, PharmD, Instructor, Department of Pharmaceutical Sciences, St. Jude Children’s Research Hospital, told Infection Control Today.
Although relatively rare, C. auris infections are on the rise. The good news is that there may be further pharmaceutical help available soon. New antifungal agents, such as Ibrexafungerp (Brexafemme) show promise in fighting C. auris infections, but more research is needed to prove their efficacy.
What Should Clinical Laboratories Do?
The CDC stresses that clinical laboratories and microbiologists working with known or suspected cases of Candida auris should first adhere to their own safety procedures. The CDC issued guidelines, but they are not meant to supersede the policies of individual labs.
The CDC also recommends that healthcare facilities and clinical laboratories that suspect they have a patient with a Candida auris infection immediately contact the CDC and state or local public health authorities for guidance.
At-home genetic test kits face scrutiny for providing information that may provide consumers with an incomplete picture of their genetic health risks and ancestry
Genetic testing for disease risk and heritage are hugely popular. But though clinical laboratory and pathology professionals understand the difference between a doctor-ordered genetic health risk (GHR) test and a direct-to-consumer (DTC) genetic test, the typical genetic test customer may not. And misunderstanding the results of a DTC at-home genetic test can lead to confusion, loss of privacy, and potential harm, according to Consumer Reports.
To help educate consumers about the “potential pitfalls” of at-home DTC testing kits offered by companies such as Ancestry and 23andMe, Consumer Reports has published an article, titled, “Read This Before You Buy a Genetic Testing Kit.” The article covers “four common claims from the manufacturers of these products, whether they deliver, and what to know about their potential pitfalls.”
Are Genetic Ancestry Tests Accurate?
Ancestry and 23andMe are the DTC genetic test industry leaders, with databases of genetic information about 18 million individuals and 10 million individuals respectively. According to a Consumer Reports survey, as of October 2020 about one in five Americans had taken a DTC genetic test. Reported reasons for doing so included:
66% of respondents wanted to learn more about their ancestry.
20% wanted to locate relatives.
18% wanted to learn more about their health.
11% wanted to learn if they have or are a carrier for any medical conditions.
3% wanted to get a medical test they could not get through their doctor.
Though DTC genetic tests remain popular, Consumer Reports is now warning consumers to view the genealogical or medical insights gleaned through these tests with caution. “If you go in there thinking that this test is going to tell you who you are, you’re going to be wrong,” Wendy Roth, PhD (above), Associate Professor of Sociology at the University of Pennsylvania, told the publication. (Photo copyright: University of Pennsylvania.)
As Consumer Reports notes, doctor-ordered genetic health risk (GHR) testing typically aims to answer a specific question about a patient’s risk for a certain disease. DTC at-home genetic testing, on the other hand, examines a “whole range of variants that have been linked—sometimes quite loosely—to a number of traits, some not related to your health at all.
“Think of it this way: When your doctor orders genetic testing, it’s akin to fishing for a particular fish, in a part of the ocean where it’s known to live,” Consumer Reports noted, “A DTC test is more like throwing a net into the ocean and seeing what comes back.”
In its article, Consumer Reports addressed four common DTC genetic test claims:
The Tests Can Find Far-Flung Relatives: While the tests can unearth people in its database whom you might be related to, 9% of respondents in the Consumer Reports survey discovered unsettling information about a relative.
Testing Can Uncover Where Your Ancestors Are From: Genetic tests may show the percentage of your DNA that comes from Europe or Asia or Africa, but accuracy depends on how many DNA samples a company has from a particular region. As genetic test manufacturers’ reference databases widen, a customer’s genetic ancestry test results can “change over time.” Also, finding a particular variation in genetic code does not definitively place someone in a specific region, or ethnic or racial group.
Genetic Tests Can Reveal Your Risk for Certain Diseases: Testing companies such as 23andMe are authorized by the Food and Drug Administration (FDA) to offer physician-mediated tests, which are analyzed in a federally-certified clinical laboratory. However, test results may provide a false sense of security because DTC tests look for only select variants known to cause disease.
The Tests Can Tell What Diet Is Best for You: Incorporating genetic information into diet advice has the potential to be transformative, but the science is not yet there to offer personalized nutritional advice.
Consumer Reports pointed to a 2020 study published in the MDPI journal Nutrients, titled, “Direct-to-Consumer Nutrigenetics Testing: An Overview,” which evaluated 45 DTC companies offering nutrigenetics testing and found a need for “specific guidelines” and “minimum quality standards” for the services offered. For example, the study authors noted that more than 900 genetic variants contribute to obesity risk. However, weight-loss advice from DTC test companies was based on a “limited set of genetic markers.”
In the Consumer Reports article, Mwenza Blell, PhD, a biosocial medical anthropologist and Rutherford Fellow and NUAcT Fellow at Newcastle University in the United Kingdom, said “genetic ancestry tests are closer to palm reading than science.”
Seattle Cancer Care Alliance and an Associate Professor of Oncology at the University of Washington, fears consumers “miss important limitations on a test’s scope” or “misunderstand critical nuances in the results.”
Cheng says the ability to use flexible or health savings accounts (HSAs) to cover the cost of 23andMe’s GHR assessments, as well as the FDA’s approval of 23andMe’s Personal Genome Service Pharmacogenetic Reports test on medication metabolism, may have added to the confusion.
“This may further mislead people into thinking these tests are clinically sound. Again, they are not,” Cheng wrote.
As an oncologist, Cheng is particularly concerned about consumer GHR testing for heritable cancer risk, which screen for only a handful of genetic variants.
“The results are inadequate for most people at high risk of cancers associated with inherited mutations in BRCA1 or BRCA2 genes, including families whose members have experienced ovarian cancer, male breast cancer, multiple early breast cancers, pancreatic cancer, or prostate cancer,” Cheng wrote. “Put simply, this recreational test has zero value for the majority of people who may need it for true medical purposes.”
DTC genetic health-risk assessments may one day lead to consumers collecting samples at home for tests that aid in the diagnosis of disease. In the meantime, clinical laboratory professionals can play a role in educating the public about the limitations of current DTC genetic test offerings.
The palm-sized device could one day be engineered to track down explosives and gas leaks or could even be used by medical laboratories to detect disease
Here’s a technology breakthrough with many implications for diagnostics and clinical laboratory testing. Researchers at the at the University of Washington (UW) are pushing the envelope on what can be achieved by combining technology with biology. They developed “Smellicopter,” a flying drone that uses a living moth antenna to hunt for odors.
According to their published study, the UW scientists believe an odor-guided drone could “reduce human hazard and drastically improve performance on tasks such as locating disaster survivors, hazardous gas leaks, incipient fires or explosives.”
“Nature really blows our human-made odor sensors out of the water,” lead author Melanie Anderson, a UW doctoral student in mechanical engineering, told UW News. “By using an actual moth antenna with Smellicopter, we’re able to get the best of both worlds: the sensitivity of a biological organism on a robotic platform where we can control its motion.”
The researchers believe their Smellicopter is the first odor-sensing flying biohybrid robot system to incorporate a live moth antenna that capitalizes on the insect’s excellent odor-detecting and odor-locating abilities.
In their paper, titled, “A Bio-Hybrid Odor-Guided Autonomous Palm-Sized Air Vehicle,” published in the IOPscience journal Bioinspiration and Biomimetics, the researchers wrote, “Biohybrid systems integrate living materials with synthetic devices, exploiting their respective advantages to solve challenging engineering problems. … Our robot is the first flying biohybrid system to successfully perform odor localization in a confined space, and it is able to do so while detecting and avoiding obstacles in its flight path. We show that insect antennae respond more quickly than metal oxide gas sensors, enabling odor localization at an improved speed over previous flying robots. By using the insect antennae, we anticipate a feasible path toward improved chemical specificity and sensitivity by leveraging recent advances in gene editing.”
How Does it Work?
In nature, a moth uses its antennae to sense chemicals in its environment and navigate toward sources of food or a potential mate.
“Cells in a moth antenna amplify chemical signals,” said study co-author Thomas Daniel, PhD, UW Professor of Biology, in UW News. “The moths do it really efficiently—one scent molecule can trigger lots of cellular responses, and that’s the trick. This process is super-efficient, specific, and fast.”
To keep the moth antennae “alive,” scientists place Manduca sexta hawk moths (above) in a refrigerator to anesthetize them before removing their antennae. Once separated from the live moth, the antenna stays “biologically and chemically active” for up to four hours. Refrigerating the antennas further extends that time span, researchers explained in the UW News article. (Photo copyright: University of Washington.)
Because the moth antenna is hollow, researchers are able to add wires into the ends of the antenna. By connecting the antenna to an electrical circuit, they can measure the average signal from all of the cells in the antenna. When compared to a metal oxide gas sensor, the antenna-powered sensor responded more quickly to a floral scent. It also took less time to recover between tracking puffs of scent.
Anderson compared the antenna-drone circuitry to a human heart monitor.
“A lot like a heart monitor, which measures the electrical voltage that is produced by the heart when it beats, we measure the electrical signal produced by the antenna when it smells odor,” Anderson told WIRED. “And very similarly, the antenna will produce these spike-shaped pulses in response to patches of odor.”
Making a Drone Hunt Like a Moth
Anderson told WIRED her team programmed the drone to hunt for odors using the same technique moths employ to stay targeted on an odor, called crosswind casting.
“If the wind shifts, or you fly a little bit off-course, then you’ll lose the odor,” Anderson said. “And so, you cast crosswind to try and pick back up that trail. And in that way, the Smellicopter gets closer and closer to the odor source.”
However, the researchers had to figure out how to keep the commercially available $195 Crazyflie drone facing upwind. The fix, co-author and co-advisor Sawyer Fuller, PhD, UW Assistant Professor of Mechanical Engineering told UW News, was to add two plastic fins to create drag and keep the vehicle on course.
“From a robotics perspective, this is genius,” Fuller said. “The classic approach in robotics is to add more sensors, and maybe build a fancy algorithm or use machine learning to estimate wind direction. It turns out, all you need is to add a fin.”
A live moth antenna is attached to wires in an arc sharp on the “Smellicopter” drone (above), developed at the University of Washington in Seattle. The autonomous drone uses the moth antenna to navigate toward smells. By connecting the antenna to a circuit board, the UW researchers were able to study the drone’s response to a puff of floral scent. The Smellicopter tracking skills proved superior to that of a human-made sensor. (Photo copyright: University of Washington.)
Other Applications for Odor Detecting Robots
While any practical clinical application of this breakthrough is years away, the scientific team’s next step is to use gene editing to engineer moths with antennae sensitive to a specific desired chemical, such as those found in explosives.
“I think it is a powerful concept,” roboticist Antonio Loquercio, a PhD candidate in machine learning at the University of Zurich who researches drone navigation, told WIRED. “Nature provides us plenty of examples of living organisms whose life depends on this capacity. This could have as well a strong impact on autonomous machines—not only drones—that could use odors to find, for example, survivors in the aftermath of an earthquake or could identify gas leaks in a man-made environment.”
Could a palm-sized autonomous device one day be used to not only track down explosives and gas leaks but also to detect disease?
As clinical pathologists and medical laboratory scientists know, dogs have demonstrated keen ability to detect disease using their heightened sense of smell.
Therefore, it is not inconceivable that smell-seeking technology might one day be part of clinical laboratory testing for certain diseases.
This latest research is another example of how breakthroughs in unrelated fields of science offer the potential for creation of diagnostic tools that one day may be useful to medical laboratories.
