Viral reservoir could be behind persistence, says study, which also suggests a blood biomarker could be found for clinical laboratory testing
Microbiologists and virologists working closely with physicians treating long COVID-19 patients will gain new insights in a study that found coronavirus spike protein in COVID-19 patients’ blood up to 12 months after diagnosis. The researchers believe their findings could be used to develop a clinical laboratory biomarker for long COVID-19.
Researchers at Brigham and Women’s Hospital and Massachusetts General Hospital said medical experts are not sure why some people have unwelcome symptoms weeks and months after a positive COVID-19 diagnosis, while others clear the infection without lingering effects.
The scientists believe if this work is validated, clinical laboratories might gain an assay to use in the diagnosis of long COVID-19.
“The half-life of spike protein in the body is pretty short, so its presence indicates that there must be some kind of active viral reservoir,” said David Walt, PhD (above), Professor of Pathology, Brigham and Women’s Hospital, and lead author of the study that found coronavirus spike protein in long COVID patients. The study findings indicate a potential clinical laboratory biomarker for long COVID-19. (Photo copyright: Brigham and Women’s Hospital.)
Viral Reservoir Possibly Behind Long COVID-19
The study suggests that SARS-CoV-2 finds a home in the body, particularly the gastrointestinal tract, “through viral reservoirs, where it continues to release spike protein and trigger inflammation,” Medical News Today reported.
Lead author of the study David Walt, PhD, Professor of Pathology, Brigham and Women’s Hospital and the Hansjörg Wyss Professor Biologically Inspired Engineering at Harvard Medical School, told The Guardian he “was motivated to carry out the study after earlier research by his colleagues detected genetic material from the COVID virus (viral RNA) in stool samples from children with multisystem inflammatory syndrome (a rare but serious condition that often strikes around four weeks after catching COVID) as well as spike protein and a marker of gut leakiness in their blood.”
Long COVID—also known as long-haul COVID, post-COVID-19, or its technical name, post-acute sequelae of COVID-19 or PASC—can involve health problems continuing weeks, months, or even years after a positive diagnosis, according to the federal Centers for Disease Control and Prevention (CDC).
Symptoms of long COVID, according to the researchers, include:
fatigue,
loss of smell,
memory loss,
gastrointestinal distress, and
shortness of breath.
“If someone could somehow get to that viral load and eliminate it, it might lead to resolution of symptoms,” Walt told the Boston Globe, which noted that the researchers may explore a clinical trial involving antiviral drugs for treatment of long COVID-19.
Clues from Earlier Studies on Long COVID-19
Medical conditions that persisted following a COVID-19 infection have been studied for some time. In fact, in an earlier study, Walt and others found children who developed a multisystem inflammation syndrome weeks after being infected by SARS-CoV-2, according to their 2021 paper published in The Journal of Clinical Investigation, titled, “Multisystem Inflammatory Syndrome in Children Is Driven by Zonulin-Dependent Loss of Gut Mucosal Barrier.”
Although these earlier studies provided clues, the cause of PASC remains unclear, the researchers noted. They planned to take a more precise look at PASC biology by using appropriate sampling and patient recruitment.
“Disentangling the complex biology of PASC will rely on the identification of biomarkers that enable classification of patient phenotypes. Here, we analyze plasma samples collected from PASC and COVID-19 patients to determine the levels of SARS-CoV-2 antigens and cytokines and identify a blood biomarker that appears in the majority of PASC patients,” the researchers wrote.
Finding a Marker of a Persistent Infection
The researchers used plasma samples from 63 people with a previous SARS-CoV-2 diagnosis (37 also had PASC), Medical News Today reported. Over a 12-month period, the researchers’ findings included:
Detection in 65% of PASC samples of full-length spike, S1 spike, and nucleocapsid throughout the year of testing.
Spike detected in 60% of PASC patient samples, and not found in the COVID-19 samples.
In an interview with Scientific American, bioengineer Zoe Swank PhD, post-doctoral researcher, Brigham and Women’s Hospital, and co-author of the study, said, “Our main hypothesis is that the spike protein is not causing the symptoms, but it’s just a marker that is released because you still have infection of some cells with SARS-CoV-2.”
In that article, Swank shared the scientists’ intent to do more research involving hundreds of samples over the course of the COVID-19 pandemic from many hospitals and people.
COVID-19 Not the Only Virus That Hangs On
Having a long-haul COVID-19 marker is a “game-changer,” according to an infectious disease expert who was not involved in the study.
“There has not so far been a clear, objective marker that is measurable in the blood of people experiencing long COVID-19,” Michael Peluso, MD, Assistant Professor, Medicine, University of California San Francisco, told Scientific American. “I hope their findings will hold up. It really would make a difference for a lot of people if a marker like this could be validated,” he added.
However, COVID-19 is not the only virus that could persist. Ebola also may linger in areas that skirt the immune system, such as the eye interior and central nervous system, according to a World Health Organization fact sheet.
Thus, medical laboratory leaders may want to follow the Brigham and Women’s Hospital research to see if the scientists validate their finding, discover a biomarker for long-haul COVID-19, and pursue a clinical trial for antiviral drugs. Such discoveries could have implications for how diagnostic professionals work with physicians to care for long COVID patients.
Clinical laboratories continue to report positive COVID-19 tests for individuals that have been vaccinated and even previously infected with the same variant of the coronavirus
Researchers across the globe continue to study the SARS-CoV-2 coronavirus and its many variants. Their goals are to curb the spread of the disease and develop new therapies and treatments for optimal patient outcomes. Now, a study conducted by scientists at the University of Missouri (UM) provides deeper insight into the processes the virus uses to mutate and overpower the human immune system. These findings could lead to improved antivirals and clinical laboratory tests for COVID-19.
The UM team identified specific mutations occurring within the virus’ spike protein that help Omicron subvariants evade existing antibodies and create an infection. These mutations may explain why some people who have had previous COVID-19 infections and/or who are fully vaccinated continue to test positive for SARS-CoV-2, and why the virus continues to evolve.
“Omicron now has more than 130 sublineages and they have been here for quite a while. We are now just finally able to detect them and differentiate among them with this research,” said Kamlendra Singh, PhD, associate research professor in the Department of Veterinary Pathobiology at UM’s College of Veterinary Medicine, in a UM press release.
“Previous variants, including Alpha, Beta, Gamma, and Delta, contributed to many of the mutations occurring now with these Omicron variants. So, our research shows how the virus has evolved over time with new mutations,” he added.
“Throughout the pandemic, the [SARS-CoV-2] virus has continued to get smarter and smarter. Even with vaccines, it continues to find new ways to mutate and evade existing antibodies,” said Kamlendra Singh, PhD (above), Associate Research Professor, College of Veterinary Medicine at University of Missouri, in a UM press release. This research team’s findings may help clinical laboratories further develop their SARS-CoV-2 antibody tests. (Photo copyright: University of Missouri.)
Antibodies for One Variant, but Not for Another
The scientists began their investigation by researching online databases that track COVID-19 cases and analyzing the protein sequences from more than 10 million Omicron-related samples that were collected from around the world since November of last year.
They examined the available sequences, structures of spike/receptor and spike/antibody complexes of the samples, and then conducted molecular dynamics simulations. The team utilized 3D modeling to locate where mutations occur and created structures of the spike protein to determine how the mutations are affected by antibodies and vaccinations.
The researchers found that the Omicron variant continues to mutate and has become extremely efficient at adaptation. Reinfections are happening because many individuals do not possess the antibodies for the new subvariants that continue to develop.
“Vaccinated individuals, or those who have previously tested positive, may have the antibodies for one variant but not necessarily for any of the other variants,” Singh explained. “The various mutations may seem like only subtle differences, but they are very important.”
The UM scientists’ research shows it is possible to differentiate Omicron subvariants from each other and pinpoint how certain mutations might become problematic for patients. According to Singh, many people can be infected with multiple variants at the same time. He is hopeful that their work will make it possible for vaccines and other treatments to specifically target different strains of the virus.
Singh also believes that the coronavirus is most likely never going to disappear from society and that new variants and their sublineages will continue to appear and evolve.
“The ultimate solution going forward will likely be the development of small molecule, antiviral drugs that target parts of the virus that do not mutate,” Singh said. “While there is no vaccine for HIV, there are very effective antiviral drugs that help those infected live a healthy life, so hopefully the same can be true with COVID-19.”
Omicron Subvariants May Be Here to Stay
“I am proud of my team’s efforts, as we have identified specific mutations for various variants throughout the pandemic, and it feels good to be contributing to research that is assisting with the situation,” Singh said. “We will continue to help out, as there will surely be new variants in the future.”
Singh is also part of a team that developed a supplement called CoroQuil-Zn, which was designed to reduce a patient’s viral load after being infected with SARS-CoV-2. The drug is currently being used in parts of India and is awaiting approval from the US Food and Drug Administration (FDA).
Clinical laboratories that perform antibody testing for SARS-CoV-2 infections should be aware that the coronavirus will likely be moving among humans for many years to come. This recent research may aid in the development of new antivirals, treatments, and vaccines that target specific subvariants for the best patient outcomes.
Findings could lead to new clinical laboratory involvement in diagnostics targeted at overweight patients
Does the SARS-CoV-2 coronavirus make us fat so it can better take over our bodies? It sounds like the plot for a science fiction horror movie! But a team of scientists in the Pacific Northwest say that is exactly what the virus does, and their findings could lead to clinical laboratories playing a role in evaluating how the virus highjacks fat cells to aid in its invasion of humans.
They found that certain types of lipids support replication of the COVID-19 virus. Their study illustrates how lipids may play a more important role in the human body than scientists previously understood.
“This is exciting work, but it’s the start of a very long journey,” said Fikadu Tafesse, PhD (left), Assistant Professor of Molecular Microbiology and Immunology, OHSU School of Medicine and corresponding author of the study in an OHSU press release. “We have an interesting observation, but we have a lot more to learn about the mechanisms of this disease.” Clinical laboratories may eventually be part of a new diagnostic process for overweight COVID-19 patients. (Photo copyright: Oregon Health and Science University.)
Does Obesity Promote COVID-19 Infection?
The OHSU and PNNL scientists performed their research by examining the effect of SARS-CoV-2 on more than 400 lipids in two different cell lines. They observed that individuals with a high body mass index (BMI) appear to be more sensitive to the COVID-19 virus.
The researchers discovered there is a tremendous shift in lipid levels in those cell lines when the virus was present, with some fats increasing by a massive 64 times! Nearly 80% of the fats in one cell line were changed by the virus and more than half of the fats were altered in the other cell line.
The lipids that were most affected by the COVID-19 virus were triglycerides which are critical to human health. Triglycerides are basically tiny bundles of fat that allow the body to store energy and maintain healthy cell membranes. When a body needs energy, these fat parcels are broken up into useful, raw materials to provide the required energy.
“Lipids are an important part of every cell. They literally hold us together by keeping our cells intact, and they’re a major source of energy storage for our bodies,” said Jennifer Kyle, PhD, in the OHSU press release. Kyle is a research scientist at PNNL who specializes in all stages of lipidomic research. “They are an attractive target for a virus,” she noted.
Stopping SARS-CoV-2 Replication
The scientists discovered that SARS-CoV-2 alters our fat-processing system by boosting the number of triglycerides in our cells and changing the body’s ability to utilize stored fat as fuel. The team also analyzed the effects of lipid levels in 24 of the virus’ 29 proteins. They identified several proteins that had a strong influence on triglyceride levels.
The team then searched databases and identified several compounds that interfered with the body’s fat-processing system by cutting off the flow of fatty fuel. They found that several of these compounds were successful at stopping the SARS-CoV-2 virus from replicating.
A synthetic organic compound known as GSK2194069, which selectively and potently inhibits fatty acid synthase (FAS), and a weight-loss medication called Orlistat, were both able to stop viral replication in the lab.
Although the scientists believe their work is an important step in understanding the SARS-CoV-2 coronavirus, they also note that their results occurred in cell culture (in vitro) and not in people (in vivo). Therefore, more research is needed to determine if the compounds will work in the same manner in human trials.
“As the virus replicates, it needs a continuous supply of energy. More triglycerides could provide that energy in the form of fatty acids. But we don’t know exactly how the virus uses these lipids to its advantage,” Tafesse said in the press release.
“Our findings fill an important gap in our understanding of host dependency factors of coronavirus infection. … In light of the evolving nature of SARS-CoV-2, it is critical that we understand the basic biology of its life cycle in order to illuminate additional avenues for protection and therapy against this global pandemic pathogen, which spreads quickly and mutates with ease,” the OHSU/PNNL scientists wrote in Nature Communications.
More research is needed to validate the findings of this study and to better understand the dynamic between lipids and SARS-CoV-2 infection. However, it is reasonable to assume that, in the future, some COVID-19 patients may require a clinical laboratory work-up to determine how the coronavirus may be hijacking their fat cells to exacerbate the illness.
Healthcare industry watchdog Group Leapfrog says that if CMS suppresses the data “all of us will be in the dark on which hospitals put us most at risk”
For some time, hospitals and clinical laboratories have struggled with transparency regulation when it comes to patient outcomes, test prices, and costs. So, it is perplexing that while that Centers for Medicare and Medicaid Services (CMS) pushes for more transparency in the cost of hospital care and quality, the federal agency also sought to limit public knowledge of 10 types of medical and surgical harm that occurred in hospitals during the COVID-19 pandemic.
And even though the CMS announced in its August 1 final rule (CMS-1771-F) that it was “pausing” its plans to suppress data relating to 10 measures that make up the Patient Safety and Adverse Events Composite (PSI 90), a part of the Hospital-Acquired Condition (HAC) Reduction Program, it is valuable for hospital and medical laboratory leaders to understand what the federal agency was seeking to accomplish.
According to USA Today, medical complications at hospitals such as pressure ulcers and falls leading to fractures would be suppressed in reports starting next year. Additionally, CMS “also would halt a program to dock the pay of the worst performers on a list of safety measures, pausing a years-long effort that links hospitals’ skill in preventing such complications to reimbursement,” Kaiser Health News reported.
The proposed rule’s executive summary reads in part, “Due to the impact of the COVID-19 PHE on measure data used in our value-based purchasing (VBP) programs, we are proposing to suppress several measures in the Hospital VBP Program and HAC Reduction Program … If finalized as proposed, for the FY 2023 program year, hospitals participating in the HAC Reduction Program will not be given a measure score, a Total HAC score, nor will hospitals receive a payment penalty.”
In a fact sheet, CMS noted that its intent in proposing the rule was neither to reward nor penalize providers at a time when they were dealing with the SARS-CoV-2 outbreak, new safety protocols for staff and patients, and an unprecedented rise in inpatient cases.
“We want the public to have complete trust in the data and will only be providing data we have determined has a high confidence of credibility and accuracy,” said CMS Chief Medical Officer Lee Fleisher, MD (above), Director of the CMS Center for Clinical Standards and Quality in a statement, Axios reported. Clinical laboratory leaders would find it more difficult to compare the performance of their hospitals against peer hospitals, should this proposed rule take effect as written. (Photo copyright: Lee Fleisher.)
Groups Opposed to the CMS Proposal
Like healthcare costs, quality data need to be accessible to the public, according to a health insurance industry representative. “Cost data, in the absence of quality data, are at best meaningless, and at worst, harmful. We see this limitation on collection and publication of data about these very serious safety issues as a step backward,” Robert Andrews, JD, CEO, Health Transformation Alliance, told Fortune.
The Leapfrog Group, a Washington, DC-based non-profit watchdog organization focused on healthcare quality and safety, urged CMS to reverse the proposal. The organization said on its website that it had collected 270 signatures on letters to CMS.
“Dangerous complications, such as sepsis, kidney harm, deep bedsores, and lung collapse, are largely preventable yet kill 25,000 people a year and harm 94,000,” wrote the Leapfrog Group in a statement. “Data on these complications is not available to the public from any other source. If CMS suppresses this data, all of us will be in the dark on which hospitals put us most at risk.”
Leah Binder, Leapfrog President/CEO, told MedPage Today she is concerned the suppression of public reporting of safety data may continue “indefinitely” because CMS does not want “to make hospitals unhappy with them.”
AHA Voices Support
Meanwhile, the American Hospital Association noted that the CMS “has made this proposal to forgo calculating certain hospital bonuses and penalties due to the impact of the pandemic,” Healthcare Dive reported.
“We agree with CMS that it would be unfair to base hospital incentives and penalties on data that have been skewed by the unprecedented impacts of the pandemic,” said Akin Demehin, AHA Senior Director, Quality and Safety Policy, in a statement to Healthcare Dive.
Though CMS’ plans to limit public knowledge of medical and surgical complications have been put on hold, medical laboratory leaders will want to stay abreast of CMS’ next steps with this final rule. Suppression of hospital harm during a period of increased demand for hospital transparency could trigger a backlash with healthcare consumers.
The federal agency shipped tests to five commercial clinical laboratory companies, augmenting efforts by public health labs
Medical laboratories in the US are ramping up their efforts to respond to an outbreak of monkeypox that has been spreading around the globe. Microbiologists and clinical laboratory scientists will be interested to learn that this infectious agent—which is new to the US—may be establishing itself in the wild rodent population in this country. If proved to be true, it means Americans would be at risk of infection from contact with rodents as well as other people.
The Centers for Disease Control and Prevention (CDC) announced on May 18 that it had identified the infection in a Massachusetts resident who had recently traveled to Canada. As of August 3, the federal agency was reporting 6,617 confirmed cases in the US.
“Because there are no other non-variola orthopoxviruses circulating in the US, a positive test result is presumed to be monkeypox,” states the APHL press release.
“As we focus on the US response, we keep a close watch on the global outbreak. Infectious diseases don’t respect borders, as we know,” said Chris Mangal (above), director of public health preparedness and response, APHL, in a press release. “I am proud of how LRN member laboratories have rapidly and effectively responded to this emergency. This is precisely what the LRN was intended to do. Should this outbreak continue to grow, preparing for expanded testing and increasing capacity beyond LRN laboratories is important to ensuring we are ready for a surge in testing.” (Photo copyright: Association of Public Health Laboratories.)
Commercial Labs Get Involved
Seeking to bolster testing capacity, the federal Department of Health and Human Services (HHS) announced on June 22 that the CDC had begun shipping OrthopoxvirusPCR tests to five commercial lab companies. They include:
“By dramatically expanding the number of testing locations throughout the country, we are making it possible for anyone who needs to be tested to do so,” said HHS Secretary Xavier Becerra in an HHS press release.
Labcorp was first out of the gate, announcing on July 6 that it was offering the CDC-developed test for its customers, as well as accepting overflow from public labs. “We will initially perform all monkeypox testing in our main North Carolina lab and have the capacity to expand to other locations nationwide should the need arise,” said Labcorp chief medical officer and president Brian Caveney, MD, in a press release.
Mayo Clinic Laboratories followed suit on July 11, announcing that the clinic’s Department of Laboratory Medicine and Pathology would perform the testing at its main facility in Rochester, Minnesota.
“Patients can access testing through Mayo Clinic healthcare professionals and will soon be able to access testing through healthcare professionals who use Mayo Clinic Laboratories as their reference laboratory,” Mayo stated in a press release.
Then, Quest Diagnostics announced on July 13 that it was testing for the virus with an internally developed PCR test, with plans to offer the CDC test in the first half of August.
The lab-developed test “was validated under CLIA federal regulations and is now performed at the company’s advanced laboratory in San Juan Capistrano, Calif.,” Quest stated in a press release.
Public Health Emergency?
Meanwhile, the CDC announced on June 28 that it had established an Emergency Operations Center to respond to the outbreak. A few weeks later, on July 23, World Health Organization (WHO) Secretary-General Tedros Adhanom Ghebreyesus, PhD, declared that the outbreak represented “a public health emergency of international concern.”
He noted that international health regulations required him to consider five elements to make such a declaration.
“WHO’s assessment is that the risk of monkeypox is moderate globally and in all regions, except in the European region where we assess the risk as high,” he said in a WHO news release. “There is also a clear risk of further international spread, although the risk of interference with international traffic remains low for the moment. So, in short, we have an outbreak that has spread around the world rapidly, through new modes of transmission, about which we understand too little, and which meets the criteria in the International Health Regulations.”
Still, public health authorities have made it clear that this is not a repeat of the COVID-19 outbreak.
“Monkeypox virus is a completely different virus than the viruses that cause COVID-19 or measles,” the CDC stated in a June 9 advisory. “It is not known to linger in the air and is not transmitted during short periods of shared airspace. Monkeypox spreads through direct contact with body fluids or sores on the body of someone who has monkeypox, or with direct contact with materials that have touched body fluids or sores, such as clothing or linens. It may also spread through respiratory secretions when people have close, face-to-face contact.”
The New York Times reported that some experts disagreed with the CDC’s assessment that the virus “is not known to linger in the air.” But Professor of Environmental Health Donald Milton, MD, DrPH, of the University of Maryland, told The Times it is still “not nearly as contagious as the coronavirus.”
The Massachusetts resident who tested positive in May was not the first known case of monkeypox in the US, however, previous cases involved travel from countries where the disease is more common. Two cases in 2021—one in Texas and one in Maryland—involved US residents who had recently returned from Nigeria, the CDC reported. And a 2003 outbreak in the Midwest was linked to rodents and other small mammals imported to Texas from Ghana in West Africa.
“Labcorp and Quest don’t dispute that in many cases, their phlebotomists are not taking blood from possible monkeypox patients,” according to CNN. “What remains unclear, after company statements and follow-ups from CNN, is whether the phlebotomists are refusing on their own to take blood or if it is the company policy that prevents them. The two testing giants say they’re reviewing their safety policies and procedures for their employees.”
One symptom of monkeypox, the CDC states, is a rash resembling pimples or blisters. Clinicians are advised that two swabs should be collected from each skin lesion, though “procedures and materials used for collecting specimens may vary depending on the phase of the rash.”
“Effective communication and precautionary measures between specimen collection teams and laboratory staff are essential to maximizing safety when manipulating specimens suspected to contain monkeypox virus,” the CDC notes. “This is especially relevant in hospital settings, where laboratories routinely process specimens from patients with a variety of infectious and/or noninfectious conditions.”
Perhaps the negative reaction to the CDC’s initial response to the COVID-19 outbreak in the US is driving the federal agency’s swift response to this new viral threat. Regardless, clinical laboratories and pathology groups will play a key role in the government’s plan to combat monkeypox in America.
