February 5, 2021 I Biomarker for patients with an increased risk of bleeding, detecting antibodies in minutes, self-swabbing just as accurate as those taken by healthcare workers, routine screening of asymptomatic healthcare personnel not an effective strategy, and breath-sampling whistle captures aerosols for COVID-19 testing. Plus: Startup develops test using genetically modified brewer’s yeast and George Mason University expands saliva-based testing on campus after successful results in the Fall.
Research News
A new study in Scientific Reports has found that a subset of COVID-19 patients have an increased bleeding risk. The study included 118 COVID-19 patients and 30 health controls with approximately half of the COVID-19 patients on mechanical ventilation and a quarter of the COVID-19 patients were able to breathe room air. They found that, compared with patients breathing room air, the patients requiring supplemental oxygen had significantly higher levels of plasminogen activator-inhibitor-1 (PAI-1), which is associated with stabilizing blood clots. Those patients with high levels of PAI-1 and tissue-type plasminogen activator (tPA), which is responsible for removing clots, were associated with worse lung function, and high tPA independently correlated with mortality. The levels of either molecule can increase independently of the other, but the research also found a change in one can have consequences on the other, according to the authors of the study. DOI:10.1038/s41598-020-80010-z
University of Illinois Grainger College of Engineering researchers have developed a fast and cost-effective COVID-19 antibody test. The research group reports that their method is a simple 15-minute sample-to-answer test that costs less than $2 per test and is used with a desktop detection system that is suitable for point-of-care settings like clinics and physician offices. They also say that this new developed method is highly sensitive and requires only a fingerstick of blood, and it could also be adapted to detect other molecules, such as antibodies to other viral pathogens, biomarkers for cardiac disease, and biomarkers for cancer. This research is published and detailed in Talanta. DOI:10.1016/j.talanta.2020.122004
A new smartphone-based COVID-19 test that delivers results in about 10 minutes has been developed by researchers at the University of Arizona. The method uses a smartphone microscope to analyze saliva samples. The technology, described in Nature Protocols, builds upon a previous version of the method where users introduce antibodies with fluorescent beads to a potentially contaminated water sample and several antibodies attach to each pathogen particle if enough particles of the pathogen are present in the sample. Under a microscope, the user can then count these clumps of fluorescent beads. Their updated version includes a 3D-printed housing for the microscope attachment and microfluidic paper chips. The new version also uses artificial intelligence (AI) to set the danger threshold and account for environmental differences, such as the type of smartphone and the quality of the paper. DOI:10.1038/s41596-020-00460-7
A team of researchers led at the University of Washington (UW) Medicine have created new protein-based biosensors that glow when mixed with components of SARS-CoV-2 or specific COVID-19 antibodies. These devices recognize specific molecules on the surface of the virus, bind to them, then emit light through a biochemical reaction. The team created the new biosensors in an effort to directly detect SARS-CoV-2 in patient samples without the need for genetic amplification. The same team of UW researchers also created biosensors that glow when mixed with COVID-19 antibodies. They demonstrated that these sensors do not react to other antibodies that might also be in the blood, including those that target other viruses. This sensitivity is important for avoiding false-positive test results, say the researchers. This work is published in Nature. DOI:10.1038/s41586-021-03258-z
At-home swabs are just as accurate at those taken by healthcare workers, according to a team of Australian investigators. Their research, published in the Journal of Clinical Microbiology, found a pooled sensitivity of 91% and specificity of 98% for self-collected upper airway swabs compared to healthcare worker swabs. The study was systematic review and meta-analysis of 20 previous studies comprising swabs of more than 3,500 individuals, comparing self-swabs with swabs collected by healthcare personnel for diagnosis of a range of upper airway pathogens. Findings were similar when only SARS-CoV-2 data was considered. The researchers believe that this level of diagnostic performance should reassure clinicians when considering at-home testing for COVID-19, and self-swabbing could offer numerous advantages that include a reduced likelihood of transmission and less discomfort for patients. DOI:10.1128/JCM.02304-20
Routine screening of asymptomatic health care workers, without a known exposure to COVID-19, is not a recommended strategy for preventing transmission of the virus, according to a new review co-authored by an infectious disease specialist at Massachusetts General Hospital (MGH). The review, published in Infection Control & Hospital Epidemiology, determined that such testing is not likely to affect transmission of COVID-19 in health care settings and could have negative consequences. After compiling data from MGH’s voluntary testing program, the researchers found that infection rates of asymptomatic health care personnel ranged from only 0.2% to 0.4%. They explain that this low prevalence means that numerous people would need to be tested to detect just one asymptomatic case, and the literature suggests that the risk of health care personnel and patients transmitting the virus to one another is very low when effective safety protocols are followed. The researchers suggest that hospitals continue to focus on interventions that are known to reduce the spread of SARS-CoV-2, such as wearing masks, testing when indicated, and screening symptomatic patients. DOI:10.1017/ice.2020.1428
A new AI-Severity Score for the assessment of COVID-19 patients has been developed by Owkin, a French-American startup pioneering AI and Federated Learning in medical research, and is published in Nature Communications. The machine learning model, trained on multimodal data sets that include computerized tomography (CT) scans of the lungs, is a plug and play that predicts the severity of a patient’s disease prognosis with a performance that surpasses all other currently published score benchmarks, according to the developers. They propose that use of these scores could support hospital resource management and planning and, when managed well, the severity score could save lives by predicting those at the highest risk for severe disease progression. DOI:10.1038/s41467-020-20657-4
Industry News
Electronic health records can be a valuable predictor of probability of death from COVID-19. This is according to a study conducted by Massachusetts General Hospital researchers. The study, published in npj Digital Medicine, describes how artificial intelligence (AI) technology was able to identify factors such as age, history of pneumonia, gender, race and comorbidities like diabetes and cancer as predictors of poor outcomes in COVID-19 patients. The team developed a set of models to forecast the most severe COVID-19 outcomes based on past medical records and to help understand the differences in risk factors across different age groups. They determined age to be the most important predictor of mortality. A history of pneumonia, uncontrolled diabetes and cancer were also identified as significant risk factors. The researchers found that race altered the odds of mortality only in the oldest cohort of patients, as African Americans were associated with a higher chance of death in that age group. Source
Meridian Bioscience announced that it will increase production capacity of the company’s SARS-CoV-2 molecular diagnostic test on its Revogene platform after receiving a $5.5 million award from the National Institutes of Health (NIH) Rapid Acceleration of Diagnostics (RADx) initiative and an additional grant from JobsOhio. The funding will aid in expanding production of Revogene test kits in the Quebec City facility and build a new semi-automated, state-of-the-art, two-line production facility near the corporate headquarters in Cincinnati, Ohio. The expansion is expected to yield a maximum capacity of 800,000 test kits per month by the end of 2021. Press Release
Oak Ridge National Laboratory (ORNL) and the University of Tennessee Health Science Center are developing a breath-sampling whistle that could make COVID-19 screening simple to do at home. The technology incorporates a unique hydrogel material to capture aerosols from exhaled breath and preserve samples, which could either be sent to a lab for analysis or transferred to an accompanying test kit that could detect the SARS-CoV-2 virus. The prototype has been 3D printed at ORNL’s Center for Nanophase Materials Sciences and designed for low-cost mass production. Press Release
A test that detects SARS-CoV-2 antibodies in 10 minutes and costs only a fifth of the market average has been developed by University of São Paulo researchers and Brazilian startup Biolinker. The device works similarly to rapid tests currently available in pharmacies. It analyzes a drop of blood, and two red LEDs light up if it detects the presence of immunoglobulin G (IgG) antibodies. The more antibodies present in the blood, the brighter the red color. The team combined a gold nanoparticle, which originates the red color, with a piece of the SARS-CoV-2 spike protein recognized by human antibodies. The researchers believe that the test could also be used to monitor COVID-19 vaccination response. Press Release
BioinFood is working on a rapid COVID-19 diagnostic test that is based on a biosensor consisting of a genetically modified brewer’s yeast, which changes color if a human ACE2 receptor expressed by the yeast’s membrane binds to the spike glycoprotein present on the surface of SARS-CoV-2. The test will likely be saliva-based and sensitivity is expected to be high, with the ability to detect the virus only a few days after infection. They plan to have the yeast emit red light for easier detection and foresee the capability for in-home use. Once the working hypothesis formulated in University of Campinas (UNICAMP) laboratories has been fully validated, BioinFood’s scientists expect the test to be brought to market and freely available for purchase by mid-2021. Press Release
George Mason University announced that it is introducing a rapid-result, saliva-based COVID-19 test that will greatly expand testing capabilities on its campuses this Spring. The use of the saliva test with the recently acquired Fluidigm system, designed to analyze large numbers of test samples, will help the university increase testing capacity from 1,000 tests per week to a goal of 10,000 by March. Mason was a model during the Fall semester for its efforts to combat the spread of the virus, with some of the lowest COVID-19 case numbers among Virginia’s largest higher education institutions, and no known transmission in its classrooms. The team at Mason is also validating a novel test that measures the body’s antibody response to the virus and COVID vaccine that will help researchers understand a person’s post-vaccination response and how long immunity lasts. Press Release