Though only in the pilot study phase, results correlate with earlier studies where both dogs and humans were able to “smell” specific diseases in people
Man’s best friend has risked life and limb to save humans for centuries. Now, researchers in Germany have discovered that pooches may be useful in the fight against COVID-19 as well, along with the added benefit that such testing would be non-invasive. In fact, some people believe disease-sniffing dogs may give clinical laboratory testing a run for its money.
Further, even if this approach were not warranted as a clinical diagnostic procedure, trained dogs could be deployed at airports, train stations, sporting events, concerts, and other public places to identify individuals who may be positive for SARS-CoV-2, the coronavirus that causes the COVID-19 illness. Such an approach would make it feasible to “screen” large numbers of people as they are on the move. Those individuals could then undergo a more precise medical laboratory test as confirmation of infections.
After only one week of training, the dogs were able to accurately detect the presence of the infection 94% of the time.
According to a live interview, which featured Holger Volk, PhD, Department Chair and Clinical Director of the Small Animal Clinic at the University of Veterinary Medicine Hannover and Maren von Köckritz-Blickwede, PhD, Professor of Biochemistry of Infections and Head of Scientific Administration and Biosafety at the Research Center for Emerging Infections and Zoonoses at TiHo, “The samples were automatically distributed at random and neither the dog handlers involved nor the researchers on site knew which samples were positive and which were used for control purposes. The dogs were able to distinguish between samples from infected (positive) and non-infected (negative) individuals with an average sensitivity of 83% and a specificity of 96%. Sensitivity refers to the detection of positive samples. The specificity designates the detection of negative control samples.
In their published study, the authors wrote, “Within randomized and automated 1,012 sample presentations, dogs achieved an overall average detection rate of 94% with 157 correct indications of positive, 792 correct rejections of negative, 33 false positive and 30 false negative indications.” They concluded, “These preliminary findings indicate that trained detection dogs can identify respiratory secretion samples from hospitalized and clinically diseased SARS-CoV-2 infected individuals by discriminating between samples from SARS-CoV-2 infected patients and negative controls. This data may form the basis for the reliable screening method of SARS-CoV-2 infected people.”
In the live interview, Dr. Köckritz-Blickwede said, “We think that this works because the metabolic processes in the body of a diseased patient are completely changed,” adding, “We think that the dogs are able to detect a specific smell of the metabolic changes that occur in those patients.”
Using Dogs as Part of Clinical Laboratory Testing
The American Kennel Club (AKC) estimates that a dog’s sense of smell is 10,000 to 100,000 times greater than that of humans. This gives dog’s the ability to detect diseases in early stages of development.
“The next steps will be that we try to differentiate between sputum samples from COVID patients versus other diseases, like, for example from influenza patients,” said Köckritz-Blickwede. “That will be quite important to be able to differentiate that in the future.”
“This method could be employed in public areas such as airports, sport events, borders or other mass gatherings as an addition to laboratory testing, helping to prevent further spreading of the virus or outbreaks,” the live interview description states.
During a pandemic, employers might be able to use dogs to screen employees as they arrive for work. Dogs also could be used as an alternative or in addition to clinical laboratory testing to help prevent the spread of COVID-19. But more work must be done.
“What has to be crystal clear is that this is just a pilot study,” said Volk. “So, there is a lot of potential to take this further to really make it possible to use these dogs in the field.”
An article on the VCA Hospitals website, titled, “How Dogs Use Smell to Perceive the World,” states that dogs devote much of their brain power to the interpretation of smells and they have more than 100 million sensory receptor sites located in their nasal cavity.
By contrast, humans have only six million sensory receptor sites in their nasal cavity. The area of a dog’s brain that is dedicated to the analysis of odors is about 40 times larger than the comparable part of a human brain and dogs are capable of detecting odors thousands of times better than humans.
The article also further explains how dog’s olfactory glands are very unique when compared to other animals and humans. “Unlike humans, dogs have an additional olfactory tool that increases their ability to smell. Jacobson’s organ is a special part of the dog’s olfactory apparatus located inside the nasal cavity and opening into the roof of the mouth behind the upper incisors. This amazing organ serves as a secondary olfactory system designed specifically for chemical communication.
“The nerves from Jacobsen’s organ lead directly to the brain and are different from the other nerves in the nose in that they do not respond to ordinary smells. In fact, these nerve cells respond to a range of substances that often have no odor at all. In other words, they work to detect “undetectable” odors.”
VCA Hospitals is a chain of veterinary hospitals with more than 1,000 facilities located in 46 states and five Canadian provinces.
Dogs are amazing, that’s for sure. But for canines to become widely used to detect infections there would have to be a way to validate each dog’s ability to detect diseases, so that the diagnostics would be consistent across all the dogs being used.
So, while there appears to be potential for utilizing a dog’s uncanny sense of smell to detect disease—including COVID-19—more research is needed before development of clinical testing can take place. And, perhaps, a set of canine billing codes.
The KCL researchers’ new models for predicting which patients will need hospitalization and breathing support may be useful for pathologists and clinical laboratory scientists
One more window into understanding the SARS-CoV-2 coronavirus may have just opened. A British study identified six distinct “clusters” of symptoms that the research scientists believe may help predict which patients diagnosed with COVID-19 will require hospitalization and respiratory support. If further research confirms these early findings, pathologists and medical laboratory managers may gain new tools to diagnose infections faster and more accurately.
Launched in March in the United Kingdom and extended to the United States and Sweden, the app has attracted more than four million users who track their health and potential COVID symptoms on a daily basis.
Increased Accuracy in Predicting COVID-19 Hospitalizations
KCL researchers identified six distinct “types” of COVID-19, each distinguished by a particular cluster of symptoms. They include headaches, muscle pains, fatigue, diarrhea, confusion, loss of appetite, shortness of breath, and more. The researchers also found that COVID-19 disease progression and outcome also vary significantly between people, ranging from mild flu-like symptoms or a simple rash to severe or fatal conditions.
Using app data logged by 1,600 users in March and April, the researchers developed an algorithm that combined information on age, gender, body mass index (BMI), and pre-existing conditions with recorded symptoms from the onset of the illness through the first five days. The researchers then tested the algorithm using a second independent dataset of 1,000 users, logged in May.
In a news release, the KCL researchers identified the six clusters of symptoms as:
Flu-like with No Fever: Headache, loss of smell, muscle pains, cough, sore throat, chest pain, no fever.
Flu-like with Fever: Headache, loss of smell, cough, sore throat, hoarseness, fever, loss of appetite.
Gastrointestinal: Headache, loss of smell, loss of appetite, diarrhea, sore throat, chest pain, no cough.
Severe Level One, Fatigue: Headache, loss of smell, cough, fever, hoarseness, chest pain, fatigue.
Severe Level Two, Confusion: Headache, loss of smell, loss of appetite, cough, fever, hoarseness, sore throat, chest pain, fatigue, confusion, muscle pain.
Severe Level Three, Abdominal and Respiratory: Headache, loss of smell, loss of appetite, cough, fever, hoarseness, sore throat, chest pain, fatigue, confusion, muscle pain, shortness of breath, diarrhea, abdominal pain.
Using the data, the researchers were able to more accurately predict—78.8% versus 69.5%—which of the six symptom clusters placed patients at higher risk of requiring hospitalization and breathing support (ventilation or additional oxygen) than with prediction models based on personal characteristics alone. For example, nearly 50% of the patients in cluster six (Severe Level Three, Abdominal and Respiratory) ended up in the hospital, compared with 16% of those in cluster one (Flu-like with No Fever).
According to the Zoe website, the ongoing research is led by:
Prof. Tim Spector, FMedSci, Professor of Genetic Epidemiology at King’s College London and Director of TwinsUK, an adult registry of twins in the United Kingdom;
Andrew Chan, MD, Professor of Medicine at Harvard Medical School, Professor of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health and Chief of the Clinical and Translational Epidemiology Unit, CTEU Massachusetts General Hospital; and
Encouraging Everyone to Use the COVID-Symptom Study App
The study points out that—broadly speaking—people with cluster four, five, or six COVID-19 symptoms tended to be older and frailer and were more likely to be overweight and have pre-existing conditions, such as diabetes or lung disease, than those with cluster one, two, or three symptoms.
Tim Spector, FMedSci, Head of the Department of Twin Research and Genetic Epidemiology, and Professor of Genetic Epidemiology at King’s College London, encourages everyone to download the COVID Symptom Study app and help increase the data available to researchers.
“Data is our most powerful tool in the fight against COVID-19,” Spector said in the KCL news release. “We urge everyone to get in the habit of using the app daily to log their health over the coming months, helping us to stay ahead of any local hotspots or a second wave of infections.”
As the body of knowledge surrounding COVID-19 grows, clinical laboratory professionals would be well advised to remain informed on further research regarding not only the potential for COVID-19 variants to exist, but also the evolving guidance on infection prevention and testing.
Pooled testing could become a critical tool for clinical laboratories to spot the SARS-CoV-2 coronavirus among asymptomatic and pre-symptomatic individuals
COVID-19 testing for individuals has expanded in the US, but the number of people actually tested remains a small proportion of the country’s total population and clinical laboratory testing supply shortages continue to hamper progress. A technique known as pooled testing may help. Federal experts hope it will substantially increase the number of individuals who are tested for the SARS-CoV-2 coronavirus before it makes a possible resurgence in the fall.
One-by-one, some of the nation’s largest clinical laboratory organizations are developing the capability to do pooled testing. For example, on July 18, the Food and Drug Administration (FDA) announced it had issued Quest Diagnostics (NYSE:DGX) an Emergency Use Authorization (EUA) for its SARS-CoV-2 rRT-PCR test, and that it is valid for up to four individual samples as a pooled test.
Quest’s rRT-PCR test was the first COVID-19 diagnostic test to be authorized for use with pooled samples, the FDA noted in a new release.
Following the announcement of Quest’s EUA, on July 24 the FDA announced LabCorp’s (NYSE:LH) EUA for its COVID-19 real-time reverse transcription polymerase chain reaction (rRT-PCR) test. The test, the EUA states, is intended for the “qualitative detection of nucleic acid from SARS-CoV-2 in upper and lower respiratory specimens” in individuals suspected of COVID-19, using “a matrix pooling strategy (i.e., group pooling strategy), containing up to five individual upper respiratory swab specimens (nasopharyngeal, mid-turbinate, anterior nares or oropharyngeal swabs) per pool and 25 specimens per matrix.”
Exponentially Increasing Testing
In pooled testing, instead of performing a coronavirus test on every specimen received by a clinical laboratory, samples from each individual specimen are taken and then combined with samples from other specimens. A single test is then performed on the entire collection of specimen samples.
If the results of the pooled samples are negative for coronavirus, it is safe to assume that all the specimens in the batch are negative for the virus. If the pooled sample comes back positive, then it will be necessary to go back to the original specimens in that pooled sample and test each specimen individually.
In an exclusive interview with Dark Daily’s sister print publication The Dark Report, Steven H. Hinrichs, MD, Chair of the Department of Pathology and Microbiology at the University of Nebraska Medical Center (UNMC), noted that one pitfall of pooled testing is that it works best in areas of low virus prevalence.
“For pooled testing, the ideal level of low prevalence would be an infection rate below 10%,” he said, adding, “For COVID-19 test manufacturers, pooled testing has the potential to reduce the number of standard tests labs run by roughly 40% to 60%, depending on the population being tested.
“Cutting the number of COVID-19 tests would be a disadvantage for test manufacturers, because pooled tests would identify large numbers of uninfected individuals who would not require standard testing with EUA tests.
“On the other hand, this policy would be a significant advantage for US labs because pooled testing would cut the number of standard tests,” he continued. “Clinical labs would save money on tests, reagents, and other supplies. It would also ease the burden on the lab’s technical staff,” Hinrichs concluded.
“In our study, we show that it’s reasonable to pool five samples, although we realized that some people may want to pool 10 samples at once,” noted Hinrichs. “But even if one sample is positive in a pool of five, then testing five samples at once saves 80% of our costs if all of those samples are negative. But, if one sample is positive, each of those five samples needs to be retested using the standard test,” Hinrichs explained.
During an American Society for Microbiology (ASM) virtual conference, Deborah Birx, MD, White House Coronavirus Response Coordinator, said, “Pooling would give us the capacity to go from a half a million tests per day to potentially five million individuals tested per day,” STAT reported.
Advantages of using pooled testing for the coronavirus include:
Expanding the number of individuals tested,
Stretching laboratory supplies, and
Reducing the costs associated with testing.
Health officials believe that individuals who have COVID-19 and are asymptomatic are largely responsible for the rising number of coronavirus cases in the US, STAT reported.
“It allows you to test more frequently in a population that may have a low prevalence of disease,” Benjamin Pinsky, MD, PhD, Associate Professor, Departments of Pathology and Medicine at Stanford University School of Medicine, told STAT. “That would allow you to test a lot of negatives, but also identify individuals who are then infected, before they develop symptoms.”
Pooled testing also could be advantageous for communities where COVID-19 is not prevalent, in neighborhoods that need to be tested during an outbreak, and for schools, universities, organizations, and businesses that want to remain safely open while periodically monitoring individuals for the virus, CNN reported.
“The goal is to increase the capacity of testing in a relatively straightforward fashion,” Pinsky told STAT. “The caveat is that by pooling the sample, you’re going to reduce the sensitivity of the test.”
According to Pinsky, “pooling only makes sense in places with low rates of COVID-19, where you expect the large majority of tests to be negative. Otherwise, too many of the pools would come back positive for it to work as a useful surveillance tool,” STAT reported.
As Clinical Lab Testing Increases, Pooled Testing for COVID-19 Could Be Critical
Pooled testing has been used in other countries, including China, to test larger amounts of people for COVID-19.
“If you look around the globe, the way people are doing a million tests or 10 million tests is they’re doing pooling,” Birx said during the ASM virtual conference, CNN reported.
In a press release, the American Clinical Laboratory Association (ACLA) stated that about 300,000 tests for COVID-19 were performed per day in labs across the US in late June. That number was up from approximately 100,000 tests being performed daily in early April.
“All across the country, clinical laboratories are increasing the number of labs processing tests, purchasing additional testing platforms, and expanding the number of suppliers to provide critical testing materials,” said Julie Khani, ACLA President in the press release. “However, the reality of this ongoing global pandemic is that testing supplies are limited. Every country across the globe is in need of essential testing supplies, like pipettes and reagents, and that demand is likely to increase in the coming months.”
Clinical laboratory managers will want to keep an eye on these developments. As the need for COVID-19 testing increases, pooled testing may provide an efficient, cost-effective way to spot the coronavirus, especially among those who are asymptomatic or pre-symptomatic and who display no symptoms.
Pooled testing could become a critical tool in the diagnosis of COVID-19 and potentially decrease the overall number of deaths.
Understanding how superspreading occurs can help clinical lab leaders slow and even prevent the spread of SARS-CoV-2 within their communities and health systems
Clinical laboratories understand the critical importance of preventing the spread of infection. However, according to the Boston Globe, researchers worldwide are learning that roughly 80% of new COVID-19 cases are caused by just 10% of infected people. Those people are called superspreaders.
It’s critical that medical laboratory managers are aware of the role superspreaders play in transmitting SARS-CoV-2, the coronavirus that causes the COVID-19 illness.
Clinical lab leaders who understand how superspreading occurs can take steps to protect staff, patients, and anyone who visits the facility. Because lab personnel such as couriers and phlebotomists, among others, come into contact with large numbers of people daily, understanding how to identify superspreaders could limit transmissions of the coronavirus within the laboratory, as well as within hospital networks.
Superspreading versus Plodding
Influenza and other viruses tend to spread in a way that epidemiologists call “plodding.” One person infects another, and the virus slowly spreads throughout the population. However, scientists around the globe are finding that SARS-CoV-2 transmission does not fit that pattern. Instead, a few infected people appear to be transmitting the virus to dozens of other people in superspreading events, Boston Globe reported.
“You can think about throwing a match at kindling. You throw one match, it might not light the kindling. You throw another match, it may not light the kindling. But then one match hits the right spot and all of a sudden the fire goes up,” Ben Althouse, PhD, principal scientist and co-chair of epidemiology at the Institute for Disease Modeling in Bellevue, Wash., told the Boston Globe.
But because roughly 90% of infected people aren’t spreading the virus, identifying who the superspreaders are can be a challenge. Nevertheless, limiting situations in which superspreading is likely to occur could greatly reduce the spread of infection.
Examples of Superspreading Events
One of the first big outbreaks in the United States was an example of a superspreading event. The Biogen (NASDAQ:BIIB) leadership conference in late February in Boston resulted in at least 99 cases of COVID-19 just in Massachusetts, reported the Boston Globe.
Several superspreading events have occurred in houses of worship. One well-documented example prompted a CDC Morbidity and Mortality Weekly Report, titled, “High SARS-CoV-2 Attack Rate Following Exposure at a Choir Practice—Skagit County, Washington.” The 122-member choir met for practice twice in March. On March 3 no one had symptoms, but one person had cold-like symptoms at the March 10 practice. Eventually, 53 members tested positive for SARS-CoV-2.
On May 30, a Texas family held a birthday party, Medical Xpress reported. Twenty-five people attended the party, which only lasted a few hours. The family followed the state’s guidelines for gatherings, however one of the hosts was infected with the SARS-CoV-2 coronavirus and wasn’t aware of it. Seven attendees contracted it, and those seven spread the virus to an additional 10 family members. A total of 18 members of a single family were infected.
There are commonalities among the documented superspreading events. Most occur indoors, often in poorly ventilated areas. Some activities cause more respiratory droplets to be expelled than others, such as singing. Some respiratory droplets are released simply by breathing, and many more are expelled when a person talks. Talking louder expels even more droplets into the air.
Are Some People More Likely to Spread the Coronavirus than Others?
The fact that so few people are responsible for the majority of transmissions of the virus raises questions. Do some people simply have more virus particles to shed? Is biology a factor?
One factor may be how long the SARS-CoV-2 coronavirus is in the body before symptoms of the COVID-19 illness manifest.
“If people got sick right away after they were infected, they might stay at home in bed, giving them few opportunities to transmit the virus,” noted Scientific American in “How ‘Superspreading’ Events Drive Most COVID-19 Spread.” However, CDC states on its website that “The incubation period for COVID-19 is thought to extend to 14 days, with a median time of 4-5 days from exposure to symptoms onset. One study reported that 97.5% of persons with COVID-19 who develop symptoms will do so within 11.5 days of SARS-CoV-2 infection.”
During that time, infected individuals may transmit the virus to dozens of other people. The CDC estimates that about 40% of transmission occurs in pre-symptomatic people, Scientific American reported.
But it’s not all bad news. The fact that circumstances may be more important than biology might be good news for clinical laboratories. “Knowing that COVID-19 is a superspreading pandemic could be a good thing. It bodes well for control,” Nelson told the Boston Globe.
Clinical laboratory managers are encouraged to follow CDC recommended safety protocols, titled, “Guidance for General Laboratory Safety Practices during the COVID-19 Pandemic.” They include social distancing, setting up one-way paths through lab areas, sanitizing shared surfaces such as counters and benchtops, and implementing flexible leave policies so that sick employees can stay home.
Following these guidelines, and being aware of superspreaders, can help medical laboratories and anatomic pathology groups keep staff and customers free of infection.
New rule for 2021 would accelerate CMS’ effort to direct patient care to lower-cost settings and improving access to care
Medicare is using data to assess where it spends the most money on clinical services. Then, guided by that data, it wants to take steps to encourage better, proactive care for patients, including directing clinical care into lower-cost settings. This has implications for clinical laboratories because such efforts can move patients into alternative care settings and make it more difficult for labs to collect lab test specimens.
In pursuing the goal of better, more proactive care, the federal Centers for Medicare and Medicaid Services (CMS) proposed changing Medicare payments for dialysis to encourage more at-home dialysis services. The initiative confirms that CMS will be steadfast in its efforts to identify high-cost diseases and sites of care, and to direct that care into lower-cost settings that reduce Medicare expenditures without sacrificing care quality.
And, though the initiative has the potential to decrease Medicare spending while improving patient compliance and quality of care, it may lead to logistical challenges for clinical laboratories that will have to collect specimens for testing from patients’ homes rather than dialysis centers.
Changing Government Barriers to Home Dialysis
A press release from the federal Department of Health and Human Services (HHS) states that Medicare spends roughly $114 billion annually on kidney disease, accounting for 20% of all fee-for-service spending. In the United States, 37-million patients suffer from chronic kidney disease and more than 726,000 have end-stage renal disease (ESRD).
“In-center dialysis can be more expensive and produce worse outcomes for patients than at-home dialysis or even a kidney transplant,” Healthcare Dive reported CMS Administrator Seema Verma telling reporters last year when President Trump announced he would sign an executive order overhauling kidney disease payment models.
In a news release, CMS pointed out that currently more than 85% of ESRD patients on Medicare travel to a facility to receive dialysis at least three times a week. On average, they spend 12 hours per week on dialysis machine away from home. The proposed rule (CMS-1732-P) for calendar year 2021 would expand the transitional add-on payment adjustment to include certain new home dialysis machines, CMS said.
COVID-19 and Threatening Traditional Dialysis Providers
Additionally, the ESRD population has the highest hospitalization rates due to COVID-19 among Medicare beneficiaries, Healthcare Finance reported.
In a statement, Kidney Care Partners (KCP) praised the changes that foster development of home dialysis machines and add new dollars for dialysis calcimimetic drugs. The coalition’s one “disappointment” was that CMS did not change the adjusters currently used in the ESRD Prospective Payment System (PPS) bundle. KCP contends the “underlying methodology used to create the current adjusters gets them wrong and leads to money being taken away from patient care.”
In its analysis of the rule change, Laffer Healthcare Intelligence warned that the federal government’s effort to “modern and optimize ESRD protocols” and its advocacy for home dialysis, artificial 3D-printed kidney development, and high rates of kidney transplants is putting “traditional facility-based dialysis providers at higher risk.”
In its healthcare investment newsletter, Laffer cited HHS Secretary Alex Azar’s “blunt language” in a March 19, 2019, speech to the National Kidney Foundation, in which Azar said his department’s plan was to “pay for Americans with kidney disease to actually get good outcomes, rather than the endless, life-consuming procedures,” as evidence of the federal mandate to overhaul the current system of kidney care.
Lower Cost versus Superior Care
But, according to Modern Healthcare, dialysis centers and patient advocacy groups are not all onboard with CMS’ plan to realign financial incentives to increase home dialysis and kidney transplants and shift providers to risk-based payments. Modern Healthcare’s review of comments on the proposed new payment models (one mandatory and four voluntary) found “some providers and patient groups think the [CMS] Innovation Center exaggerated the clinical evidence, and choosing whether to receive treatment at home or in a dialysis center should be based on patient choice, not financial rewards.”
But Strive Health co-founder and Chief Revenue Officer Robert Badal believes the new rule has the potential to “drive meaningful savings in dialysis costs and improvements in member care” for Medicare Advantage (MA) organizations.
“Skeptics of the new rule claim it may negatively impact access for members who dialyze in the outpatient setting, but this argument appears unfounded,” Badal wrote in an article posted on the Strive Health website. “Existing MA members with ESRD will maintain access to their dialysis provider, whether their provider is contracted or not, and continuity-of-care requirements ensure that dialysis providers will continue treatments and not displace the member. Even as such, we have talked to dozens of payors about the new rule, and the consensus has been a member-centric view of the changes. In fact, many payors are planning to keep their [participating] networks completely unchanged.”
The rule change builds on President Trump’s 2019 executive order launching his “Advancing American Kidney Health” initiative. Its goals are to:
Reduce the number of Americans developing ESRD by 25% by 2030;
Have 80% of new ESRD patients in 2025 either receiving dialysis at home or receiving a transplant; and
Double the number of kidneys available for transplant by 2030.
This proposed CMS rule change is further evidence that the shift from “volume to value” in healthcare may impact clinical laboratories and pathology groups in unexpected ways.