Doctors report difficulty differentiating COVID-19 from other viral infections, impacting clinical laboratory test orders
Because the SARS-CoV-2 coronavirus is in the same family of viruses that cause the common cold and influenza, virologists expected this virus—which caused the global COVID-19 pandemic—would evolve and mutate into a milder form of infection. Early evidence from this influenza season seems consistent with these expectations in ways that will influence how clinical laboratories offer tests for different respiratory viruses.
While new variants of the SARS-CoV-2 virus continue to appear, indications are that early in this flu season individuals infected with the more recent variants are experiencing milder symptoms when compared to the last few years. Doctors report they find it increasingly difficult to distinguish COVID-19 infections from allergies or the common cold because patients’ symptoms are less severe, according to NBC News.
This, of course, makes it challenging for doctors to know the most appropriate clinical laboratory tests to order to help them make accurate diagnoses.
“It isn’t the same typical symptoms that we were seeing before. It’s a lot of congestion, sometimes sneezing, usually a mild sore throat,” Erick Eiting, MD, Vice Chair of Operations for Emergency Medicine at Mount Sinai Hospital in New York City, told NBC News. “Just about everyone who I’ve seen has had really mild symptoms. The only way that we knew that it was COVID was because we happened to be testing them.” Knowing which tests for respiratory viruses that clinical laboratories need to perform may soon be the challenge for doctors. (Photo copyright: Mt. Sinai.)
Milder COVID-19 Symptoms Follow a Pattern
Previous hallmarks of a COVID-19 infection included:
Loss of taste,
loss of smell,
dry cough,
fever,
sore throat,
diarrhea,
body aches,
headaches.
However, physicians now observe milder symptoms of the infection that follow a distinct pattern and which are mostly concentrated in the upper respiratory tract.
Grace McComsey, MD, Vice President of Research and Associate Chief Scientific Officer at University Hospitals Health System (UH) in Cleveland, Ohio, told NBC News that some patients have described their throat pain as “a burning sensation like they never had, even with Strep in the past.”
“Then, as soon as the congestion happens, it seems like the throat gets better,” she added.
In addition to the congestion, some patients are experiencing:
headache,
fever,
chills,
fatigue,
muscle aches,
post-nasal drip.
McComsey noted that fatigue and muscle aches usually only last a couple of days, but that the congestion can sometimes last a few weeks. She also estimated that only around 10-20% of her newest COVID patients are losing their sense of smell or taste, whereas early in the pandemic that number was closer to 60-70% of her patients.
Doctors also noted that fewer patients are requiring hospitalization and that many recover without the use of antivirals or other treatments.
“Especially since July, when this recent mini-surge started, younger people that have upper respiratory symptoms—cough, runny nose, sore throat, fever and chills—99% of the time they go home with supportive care,” said Michael Daignault, MD, an emergency physician at Providence Saint Joseph Medical Center in Burbank, California.
Milder SARS-CoV-2 Variants Should Still be Taken Seriously
Doctors have varying opinions regarding why the current COVID-19 variants are milder. Some believe the recent variants simply aren’t as good at infecting the lungs as previous variants.
“Overall, the severity of COVID-19 is much lower than it was a year ago and two years ago,” Dan Barouch, MD, PhD, Director of the Center for Virology and Vaccine Research at Beth Israel Deaconess Medical Center, told NBC News. “That’s not because the variants are less robust. It’s because the immune responses are higher.”
McComsey added that she doesn’t think mild cases should be ignored as she is still seeing new cases of long COVID with rapid heart rate and exercise intolerance being among the most common lingering symptoms. Re-infections also add to the risks associated with long COVID.
“What we’re seeing in long COVID clinics is not just the older strains that continue to be symptomatic and not getting better—we’re adding to that number with the new strain as well,” McComsey said. “That’s why I’m not taking this new wave any less seriously.”
Clinical Laboratory COVID-19 Testing May Decrease
According to Andrew Read, PhD, Interim Senior Vice President for Research and Evan Pugh University Professor of Biology and Entomology at Pennsylvania State University, there is nothing unexpected or startling about the coronavirus acquiring new mutations.
“When a mutation confers an interesting new trick that’s got an advantage, it’s going to be popping up in many different places,” Read told the New York Times. “Everything we see is just consistent with how you imagine virus evolution proceeding in a situation where a new virus has jumped into a novel host population.”
Data from the Centers for Disease Control and Prevention’s COVID-19 Data Tracker—which reports weekly hospitalizations, deaths, emergency department (ED) visits, and COVID-19 test positivity results—shows infection trends fluctuating, but overall, they are decreasing.
For the week of October 21, 2023, there were 16,186 hospitalizations due to COVID-19 compared to the highest week recorded (January 15, 2022) with 150,674 hospitalizations nationwide.
The highest number of deaths reported in a single week were 25,974 for the week of January 8, 2021, while 637 patients perished from COVID-19 during the week of October 21, 2023.
In January of 2021, COVID accounted for 13.8% of all ED visits and in October 2023, COVID-19 was responsible for 1.3% of ED visits.
“What I think we’re seeing is the virus continuing to evolve, and then leading to waves of infection, hopefully mostly mild in severity,” Barouch told The New York Times.
As severity of COVID-19 infections continues to fall, so, presumably, will demand for COVID-19 testing which has been a source of revenue for clinical laboratories for several years.
The 80 scientists and engineers that comprise the consortium believe synthetic biology can address key challenges in health and medicine, but technical hurdles remain
Synthetic biology now has a 20-year development roadmap. Many predict this fast-moving field of science will deliver valuable products that can be used in diagnostics—including clinical laboratory tests, therapeutics, and other healthcare products.
Eighty scientists from universities and companies around the world that comprise the Engineering Biology Research Consortium (EBRC) recently published the 20-year roadmap. They designed it to “provide researchers and other stakeholders (including government funders)” with what they hope will be “a go-to resource for engineering/synthetic biology research and related endeavors,” states the EBRC Roadmap website.
Medical laboratories and clinical pathologists may soon have new tools and therapies for targeting specific diseases. The EBRC defines synthetic biology as “the design and construction of new biological entities such as enzymes, genetic circuits, and cells or the redesign of existing biological systems. Synthetic biology builds on the advances in molecular, cell, and systems biology and seeks to transform biology in the same way that synthesis transformed chemistry and integrated circuit design transformed computing.”
Synthetic biology is an expanding field and there are predictions that it may produce research findings that can be adapted for use in clinical pathology diagnostics and treatment for chronic diseases, such as cancer.
Another goal of the roadmap is to encourage federal
government funding for synthetic biology.
“The question for government is: If all of these avenues are now open for biotechnology development, how does the US stay ahead in those developments as a country?” said Douglas Friedman, EBRC’s Executive Director, in a news release. “This field has the ability to be truly impactful for society and we need to identify engineering biology as a national priority, organize around that national priority, and take action based on it.”
Designing or Redesigning Life Forms for Specific
Applications
Synthetic biology is an interdisciplinary field that combines
elements of engineering, biology, chemistry, and computer science. It enables
the design and construction of new life forms—or redesign of existing ones—for
a multitude of applications in medicine and other fields.
Another recent example comes from the Wyss Institute at Harvard. Scientist there developed a direct-to-consumer molecular diagnostics platform called INSPECTR that, they say, uses programmable synthetic biosensors to detect infectious pathogens or host cells.
The Wyss Institute says on its website that the platform can
be packaged as a low-cost, direct-to-consumer test similar to a home pregnancy
test. “This novel approach combines the specificity, rapid development, and
broad applicability of a molecular diagnostic with the low-cost, stability, and
direct-to-consumer applicability of lateral flow immunoassays.”
In March, Harvard announced that it had licensed the technology to Sherlock Biosciences.
Howard Salis, PhD (above), Associate Professor of biological engineering and chemical engineering at Pennsylvania State University (Penn State), co-chaired the EBRC Roadmapping Working Group that produced the roadmap. In a Penn State news story, Salis explained synthetic biology’s potential. “There are both traditional and startup companies leveraging synthetic biology technologies to develop novel biotech products,” he said. “Organisms that produce biorenewable materials; diagnostics to detect the Zika virus, Ebola and tuberculosis; and soil bacteria that fix nitrogen into ammonia for improved plant growth.” (Photo copyright: Twitter.)
Fundamental Challenges with Synthetic Biology
The proponents of synthetic biology hope to make it easier
to design and build these systems, in much the same way computer engineers
design integrated circuits and processors. The EBRC Roadmap may help scientist
worldwide achieve this goal.
However, in “What is Synthetic/Engineering Biology?” the EBRC also identifies the fundamental challenges facing the field. Namely, the complexity and unpredictability inherent in biology, and a limited understanding of how biological components interact.
The EBRC roadmap report, “Engineering Biology: A Research
Roadmap for the Next-Generation Bioeconomy,” covers five categories of applications:
Health and medicine are of primary interest to pathologists.
Synthetic Biology in Health and Medicine
The Health and Medicine section of the report identifies
four broad societal challenges that the EBRC believes can be addressed by
synthetic biology. For each, the report specifies engineering biology
objectives, including efforts to develop new diagnostic technologies. They
include:
Existing and emerging infectious diseases: Objectives include development of tools for treating infections, improving immunity, reducing dependence on antibiotics, and diagnosing antimicrobial-resistant infections. The authors also foresee tools for rapid characterization and response to “known and unknown pathogens in real time at population scales.”
Non-communicable diseases and disorders, including cancer, heart disease, and diabetes: Objectives include development of biosensors that will measure metabolites and other biomolecules in vivo. Also: tools for identifying patient-specific drugs; tools for delivering gene therapies; and genetic circuits that will foster tissue formation and repair.
Environmental health threats, such as toxins, pollution, and injury: Objectives include systems that will integrate wearable tech with living cells, improve interaction with prosthetics, prevent rejection of transplanted organs, and detect and repair of biochemical damage.
Healthcare access and personalized medicine: The authors believe that synthetic biology can enable personalized treatments and make new therapies more affordable.
Technical Themes
In addition to these applications, the report identifies
four “technical themes,” broad categories of technology that will spur the
advancement of synthetic biology:
Gene editing, synthesis, and assembly: This refers to tools for producing chromosomal DNA and engineering whole genomes.
Biomolecule, pathway, and circuit engineering: This “focuses on the importance, challenges, and goals of engineering individual biomolecules themselves to have expanded or new functions,” the roadmap states. This theme also covers efforts to combine biological components, both natural and non-natural, into larger, more-complex systems.
Host and consortia engineering: This “spans the development of cell-free systems, synthetic cells, single-cell organisms, multicellular tissues and whole organisms, and microbial consortia and biomes,” the roadmap states.
Data Integration, modeling, and automation: This refers to the ability to apply engineering principles of Design, Build, Test and Learn to synthetic biology.
The roadmap also describes the current state of each
technology and projects likely milestones at two, five, 10, and 20 years into
the future. The 2- and 5-year milestones are based on “current or recently
implemented funding programs, as well as existing infrastructure and facilities
resources,” the report says.
The longer-term milestones are more ambitious and may
require “significant technical advancements and/or increased funding and
resources and new and improved infrastructure.”
Synthetic biology is a significant technology that could
bring about major changes in clinical pathology diagnostics and treatments.
It’s well worth watching.
Pathologists will be interested to learn that this latest version of the acoustic tweezer device requires about five hours to identify the CTCs in a sample of blood
Medical laboratory leaders and pathologists are well aware that circulating tumor cells (CTCs) released by primary tumors into the bloodstream are fragile and easily damaged. Many studies have sought to find ways to separate CTCs from surrounding cells. Such a process could then be used as an early-detection biomarker to detect cancer from a sample of blood.
One team of researchers believe it has a way to accomplish this. These researchers are using sound waves to gently detect and isolate CTCs in blood samples. In turn, this could make it possible to diagnose cancer using “liquid biopsies” as opposed to invasive conventional biopsies.
Innovative device uses acoustic sound waves to gently separate circulating cancer cells from white blood cells
In many respects, the ability to separate and identify circulating tumor cells (CTCs) is one of the holy grails of cancer diagnostics. It is widely believed that a clinical laboratory test that can effectively identify CTCs would contribute to earlier detection of cancer and improved outcomes for caner patients.
Pathologists will be interested to learn about a useful new tool that can flag circulating tumor cells. Researchers say that this approach enables them to determine if a cancerous tumor is going to spread, without tagging tumor cells with harsh chemicals. This gentler alternative to current diagnostic methods involves an innovative device that uses “tilted” sound waves to sort tumor cells from white blood cells, noted a report in Headlines & Global News.
Researchers at Penn State identified 160,000 ‘transcription initiation machines’ throughout the human genome
DNA “dark matter” may have something in common with comedian Rodney Dangerfield, who liked to say, “I don’t get no respect!” As many pathologists know, for years the human exome that has been the focus of most research. This is the 1% of the human genome that contains the genes that produce proteins and do other useful functions.
Meanwhile, the remaining 99% of the human genome—sometimes called “junk DNA” and generally known as dark matter—got relatively little attention from researchers. But that is changing. At Pennsylvania State University, a research team has discovered that coding and noncoding RNA, or genomic dark matter, originates at the same types of locations along the human genome. (more…)
