A Machine-Generated View of the Role of Blood Glucose Levels in the Severity of COVID-19

Abstract:

SARS-CoV-2 started spreading toward the end of 2019 causing COVID-19, a disease that reached pandemic proportions among the human population within months. The reasons for the spectrum of differences in the severity of the disease across the population, and in particular why the disease affects more severely the aging population and those with specific preconditions are unclear. We developed machine learning models to mine 240,000 scientific articles openly accessible in the CORD-19 database, and constructed knowledge graphs to synthesize the extracted information and navigate the collective knowledge in an attempt to search for a potential common underlying reason for disease severity. The machine-driven framework we developed repeatedly pointed to elevated blood glucose as a key facilitator in the progression of COVID-19. Indeed, when we systematically retraced the steps of the SARS-CoV-2 infection, we found evidence linking elevated glucose to each major step of the life-cycle of the virus, progression of the disease, and presentation of symptoms.

Specifically, elevations of glucose provide ideal conditions for the virus to evade and weaken the first level of the immune defense system in the lungs, gain access to deep alveolar cells, bind to the ACE2 receptor and enter the pulmonary cells, accelerate replication of the virus within cells increasing cell death and inducing an pulmonary inflammatory response, which overwhelms an already weakened innate immune system to trigger an avalanche of systemic infections, inflammation and cell damage, a cytokine storm and thrombotic events. We tested the feasibility of the hypothesis by manually reviewing the literature referenced by the machine-generated synthesis, reconstructing atomistically the virus at the surface of the pulmonary airways, and performing quantitative computational modeling of the effects of glucose levels on the infection process.

We conclude that elevation in glucose levels can facilitate the progression of the disease through multiple mechanisms and can explain much of the differences in disease severity seen across the population. The study provides diagnostic considerations, new areas of research and potential treatments, and cautions on treatment strategies and critical care conditions that induce elevations in blood glucose levels.

Source: Logette E, Lorin C, Favreau C, et al. A Machine-Generated View of the Role of Blood Glucose Levels in the Severity of COVID-19. Front Public Health. 2021;9:695139. Published 2021 Jul 28. doi:10.3389/fpubh.2021.695139 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8356061/ (Full text)

Relationship Between Myocardial Injury During Index Hospitalization for SARS-CoV-2 Infection and Longer-Term Outcomes

Abstract:

Background: Myocardial injury in patients with COVID-19 is associated with increased mortality during index hospitalization; however, the relationship to long-term sequelae of SARS-CoV-2 is unknown. This study assessed the relationship between myocardial injury (high-sensitivity cardiac troponin T level) during index hospitalization for COVID-19 and longer-term outcomes.

Methods and Results: This is a prospective cohort of patients who were hospitalized at a single center between March and May 2020 with SARS-CoV-2. Cardiac biomarkers were systematically collected. Outcomes were adjudicated and stratified on the basis of myocardial injury. The study cohort includes 483 patients who had high-sensitivity cardiac troponin T data during their index hospitalization. During index hospitalization, 91 (18.8%) died, 70 (14.4%) had thrombotic complications, and 126 (25.6%) had cardiovascular complications. By 12 months, 107 (22.2%) died. During index hospitalization, 301 (62.3%) had cardiac injury (high-sensitivity cardiac troponin T≧14 ng/L); these patients had 28.6%, 32.2%, and 33.2% mortality during index hospitalization, at 6 months, and at 12 months, respectively, compared with 4.1%, 4.9%, and 4.9% mortality for those with low-level positive troponin and 0%, 0%, and 0% for those with undetectable troponin. Of 392 (81.2%) patients who survived the index hospitalization, 94 (24%) had at least 1 readmission within 12 months, of whom 61 (65%) had myocardial injury during the index hospitalization. Of 377 (96%) patients who were alive and had follow-up after the index hospitalization, 211 (56%) patients had a documented, detailed clinical assessment at 6 months. A total of 78 of 211 (37.0%) had ongoing COVID-19-related symptoms; 34 of 211 (16.1%) had neurocognitive decline, 8 of 211 (3.8%) had increased supplemental oxygen requirements, and 42 of 211 (19.9%) had worsening functional status.

Conclusions: Myocardial injury during index hospitalization for COVID-19 was associated with increased mortality and may predict who are more likely to have postacute sequelae of COVID-19. Among patients who survived their index hospitalization, the incremental mortality through 12 months was low, even among troponin-positive patients.

Source: Weber B, Siddiqi H, Zhou G, Vieira J, Kim A, Rutherford H, Mitre X, Feeley M, Oganezova K, Varshney AS, Bhatt AS, Nauffal V, Atri DS, Blankstein R, Karlson EW, Di Carli M, Baden LR, Bhatt DL, Woolley AE. Relationship Between Myocardial Injury During Index Hospitalization for SARS-CoV-2 Infection and Longer-Term Outcomes. J Am Heart Assoc. 2022 Jan 4;11(1):e022010. doi: 10.1161/JAHA.121.022010. Epub 2021 Dec 31. PMID: 34970914. https://www.ahajournals.org/doi/10.1161/JAHA.121.022010 (Full text)

Combined triple treatment of fibrin amyloid microclots and platelet pathology in individuals with Long COVID/ Post-Acute Sequelae of COVID-19 (PASC) can resolve their persistent symptoms

Abstract:

We recognise that fibrin(ogen) amyloid microclots and platelet hyperactivation, that we have previously observed in COVID-19 and Long COVID/Post-Acute Sequelae of COVID-19 (PASC) patients, might form a suitable set of foci for the clinical treatment of the symptoms of long COVID/PASC. We first report on the comorbidities and symptoms found in a cohort of 845 South African Long COVID/PASC patients who filled in the South African Long COVID/PASC registry, of which hypertension and high cholesterol levels (dyslipidaemia) were the most important comorbidities. The gender balance (70% female) and the most commonly reported Long COVID/PASC symptoms (fatigue, brain fog, loss of concentration and forgetfulness, shortness of breath, as well as joint and muscle pains) were comparable to those reported elsewhere. This suggests that our sample was not at all atypical. Using a previously published scoring system for fibrin amyloid microclots and platelet pathology, we analysed blood samples from 70 patients, and report the presence of significant fibrin amyloid microclots and platelet pathology in all cases; these were associated with Long COVID/PASC symptoms that persisted after the recovery from acute COVID-19.

A subset of 24 patients was treated with one month of dual antiplatelet therapy (DAPT) (Clopidogrel 75mg/Aspirin 75mg) once a day, as well as a direct oral anticoagulant (DOAC) (Apixiban) 5 mg twice a day. A proton pump inhibitor (PPI) pantoprazole 40 mg/day was also prescribed for gastric protection. Such a regime must only be followed under strict and qualified medical guidance to obviate any dangers, especially haemorrhagic bleeding, and of the therapy as a whole. Thromboelastography (TEG®) was used to assist in determining their clotting status.

Each of the 24 treated cases reported that their main symptoms were resolved and fatigue as the main symptom was relieved, and this was also reflected in a decrease of both the fibrin amyloid microclots and platelet pathology scores. Nine patients were genotyped for genetic variation in homocysteine metabolism implicated in hypertension, a common COVID-19 co-morbidity reported in both patients found to be homozygous for the risk-associated MTHFR 677 T-allele. Fibrin amyloid microclots that block capillaries and inhibit the transport of O2 to tissues, accompanied by platelet hyperactivation, provide a ready explanation for the symptoms of Long COVID/PASC. The removal and reversal of these underlying endotheliopathies provide an important treatment option that seems to be highly efficacious, and warrants controlled clinical studies.

Source: Pretorius, Etheresia & Venter, Chantelle & Laubscher, Gert & Kotze, Maritha & Moremi, Kelebogile & Oladejo, Sunday & Watson, Liam & Rajaratnam, Kanshu & Watson, Bruce & Kell, Douglas. Combined triple treatment of fibrin amyloid microclots and platelet pathology in individuals with Long COVID/ Post-Acute Sequelae of COVID-19 (PASC) can resolve their persistent symptoms. Preprint from 28 Dec 2021 https://assets.researchsquare.com/files/rs-1205453/v1_covered.pdf?c=1640805028 (Full text)

Fatigue and Cognitive Impairment in Post-COVID-19 Syndrome: A Systematic Review and Meta-Analysis

Abstract:

Importance: COVID-19 is associated with clinically significant symptoms despite resolution of the acute infection (i.e., post-COVID-19 syndrome). Fatigue and cognitive impairment are amongst the most common and debilitating symptoms of post-COVID-19 syndrome.

Objective: To quantify the proportion of individuals experiencing fatigue and cognitive impairment 12 or more weeks following COVID-19 diagnosis, and to characterize the inflammatory correlates and functional consequences of post-COVID-19 syndrome.

Data sources: Systematic searches were conducted without language restrictions from database inception to June 8, 2021 on PubMed/MEDLINE, The Cochrane Library, PsycInfo, Embase, Web of Science, Google/Google Scholar, and select reference lists.

Study selection: Primary research articles which evaluated individuals at least 12 weeks after confirmed COVID-19 diagnosis and specifically reported on fatigue, cognitive impairment, inflammatory parameters, and/or functional outcomes were selected.

Data extraction & synthesis: Two reviewers independently extracted published summary data and assessed methodological quality and risk of bias. A meta-analysis of proportions was conducted to pool Freeman-Turkey double arcsine transformed proportions using the random-effects restricted maximum-likelihood model.

Main outcomes & measures: The co-primary outcomes were the proportions of individuals reporting fatigue and cognitive impairment, respectively, 12 or more weeks after COVID-19 infection. The secondary outcomes were inflammatory correlates and functional consequences of post-COVID-19 syndrome.

Results: The literature search yielded 10,979 studies, and 81 studies were selected for inclusion. The fatigue meta-analysis comprised 68 studies, the cognitive impairment meta-analysis comprised 43 studies, and 48 studies were included in the narrative synthesis. Meta-analysis revealed that the proportion of individuals experiencing fatigue 12 or more weeks following COVID-19 diagnosis was 0.32 (95% CI, 0.27, 0.37; p < 0.001; n = 25,268; I2=99.1%). The proportion of individuals exhibiting cognitive impairment was 0.22 (95% CI, 0.17, 0.28; p < 0.001; n = 13,232; I2=98.0). Moreover, narrative synthesis revealed elevations in proinflammatory markers and considerable functional impairment in a subset of individuals.

Conclusions & relevance: A significant proportion of individuals experience persistent fatigue and/or cognitive impairment following resolution of acute COVID-19. The frequency and debilitating nature of the foregoing symptoms provides the impetus to characterize the underlying neurobiological substrates and how to best treat these phenomena.

Study Registration PROSPERO (CRD42021256965).

Source: Ceban F, Ling S, Lui LMW, Lee Y, Gill H, Teopiz KM, Rodrigues NB, Subramaniapillai M, Di Vincenzo JD, Cao B, Lin K, Mansur RB, Ho RC, Rosenblat JD, Miskowiak KW, Vinberg M, Maletic V, McIntyre RS. Fatigue and Cognitive Impairment in Post-COVID-19 Syndrome: A Systematic Review and Meta-Analysis. Brain Behav Immun. 2021 Dec 29;101:93–135. doi: 10.1016/j.bbi.2021.12.020. Epub ahead of print. PMID: 34973396; PMCID: PMC8715665. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8715665/ (Full text)

Sulodexide in the treatment of patients with long COVID 19 symptoms and endothelial dysfunction: The results of TUN-EndCOV study

Abstract:

Background: Endothelial dysfunction is probably one of the mechanisms of long COVID-19 symptoms. Sulodexide has pleiotropic properties within the vascular endothelium that can prove beneficial in the long COVID-19 symptoms.

Purpose: We aimed to evaluate the effect of sulodexide when used in patients with endothelial dysfunction and long COVID-19 symptoms.

Methods: We conducted a prospective multicenter longitudinal case-control study. Endothelial function was evaluated with DTM “E4-Diagnose” Polymath based on the Endothelium Quality Index (EQI). A group of patients with endothelial dysfunction (EQI < 2.0) received sulodexide. All the patients were followed-up 21 days after inclusion. Primary outcomes were defined as endothelial function amelioration (delta EQI) and long COVID-19 symptoms evolution during the follow-up.

Results: A total of 410 patients were included in this study. Patients were included at an average time of 1.89 ± 1.2 month after COVID-19 infection. At inclusion, 210 (51.2%) patients had an EQI < 2. The median age was 49 ± 13.8 (18–80) years. Among the patients with endothelial dysfunction, only 79 patients received sulodexide. Patients in sulodexide group had lower EQI than the non-medical intervention group (0.94 ± 0.6 vs. 1.52 ± 0.4; P < 10−3). They were more diabetic, hypertensive, had more coronary artery disease and received more long-term medications (aspirin, Bblockers and statins) than the others (P = 0.01, 0.002, 0.01, 0.009, 0.001 and 0.01, respectively). At the 21-days follow-up, patients in sulodexide group presented lower long COVID symptoms especially chest pain, palpitations, fatigue and neuro-cognitive difficulties associated to a significant amelioration of endothelial function (delta EQI 1.26 ± 1.07 vs. 0.22 ± 0.7; P < 10−3).

Conclusion: Sulodexide in patients with long COVID-19 may be a good intervention to ameliorate chest pain, palpitations, fatigue and neuro-cognitive difficulties associated to endothelial dysfunction.

Source: S. Charfeddine, H. Ibn Hadjamor, S. Torjmen, S. Kraiem, R. Hammami, A. Bahloul, N. Kallel, N. Moussa, I. Touil, J. Jdidi, S. Abdesselem, L. Abid. Sulodexide in the treatment of patients with long COVID 19 symptoms and endothelial dysfunction: The results of TUN-EndCOV study,
Archives of Cardiovascular Diseases Supplements. Volume 14, Issue 1, 2022, Page 127, ISSN 1878-6480,
https://doi.org/10.1016/j.acvdsp.2021.10.007. (https://www.sciencedirect.com/science/article/pii/S1878648021006455)

Endothelial dysfunction is the key of long COVID-19 symptoms: The results of TUN-EndCOV study

Abstract:

Background: The COVID-19 disease is a multisystem disease due to in part to the vascular endothelium injury. Lasting effects and long-term sequalae could persist after the infection and may be due to persistent endothelial dysfunction.

Purpose: Our study focused on the study of endothelial function measurement by digital thermal monitoring (DTM) of endothelial quality index with E4 diagnosis Polymath in a large cohort of long COVID-19 patients to determine whether long COVID-19 symptoms are due to endothelial dysfunction.

Methods: This is a prospective multicenter longitudinal observational cohort study. Endothelial function was evaluated with “E4-Diagnose” Polymath Tunisia based on the Endothelium Quality Index (EQI). A complete echocardiographic evaluation analysis was performed. Primary outcomes were defined as the occurrence of long COVID-19 symptoms in patients with endothelial dysfunction measured by EQI.

Results: A total of 798 patients were included in this study. Patients were included at an average time of 68.93 ± 43.1 days. The mean EQI was 2.02 ± 0.99 [0–5]. A total of 397 (49.7%) patients had poor or very poor EQI and 211 (26.4%) patients had very poor EQI. The median age was 49.94 ± 14.2 (18–80) years. A total of 618 patients (77.4%) had long COVID-19 symptoms. Patients with long COVID-19 symptoms had a reduced EQI (1.99 ± 0.97 vs. 2.09 ± 1.05, P = 0.24). Among long COVID-19 symptoms, fatigue was the most common symptom reported in 42.2%. Fatigue and chest pain were significantly associated to the endothelial dysfunction (P = 0.04 and 0.001 respectively). Patients with chest pain had significantly lower EQI (1.74 ± 1.0 vs. 2.09 ± 0.9, P ≤ 10−3) and LVGLS (−16.35 ± 3.0 vs. −17.16 ± 2.5, P = 0.04).

Conclusion: Long COVID-19 symptoms specifically chest pain and fatigue are due to persistent poor endothelial quality index. These findings allow a better care of patients with long COVID-19 symptoms.

Source: S. Charfeddine, H. Ibnhadjamor, S. Torjmen, S. Kraiem, R. Hammami, A. Bahloul, N. Kallel, N. Moussa, I. Touil, S. Milouchi, J. Elghoul, Z. Meddeb, Y. Thabet, J. Jdidi, K. Bouslema, S. Abdesselem, L. Abid. Endothelial dysfunction is the key of long COVID-19 symptoms: The results of TUN-EndCOV study. Archives of Cardiovascular Diseases Supplements, Volume 14, Issue 1, 2022, Page 126, ISSN 1878-6480, https://doi.org/10.1016/j.acvdsp.2021.10.004. (https://www.sciencedirect.com/science/article/pii/S187864802100642X)

Impaired systemic oxygen extraction long after mild COVID-19: potential perioperative implications

Editor:

The extraordinary number of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infections world-wide has made it inevitable that patients who have recovered from COVID-19 will present for anaesthesia and surgery. Recent data indicate that in the United States alone, roughly one-third of the population had been infected by the end of 20201. With this in mind, we read with interest the recent correspondence by Silvapulle and colleagues2 underscoring the wide range of symptoms that often follow recovery from COVID-19 and the complexity of considering residual physiologic abnormalities when assessing perioperative risk. They note that patients suffering from “long COVID” have been reported to exhibit demonstrable abnormalities in several biomarkers as well as cardiac, neurologic, haematologic, renal, hepatic, and endocrine impairment. Based on current evidence, the authors suggest that patients previously experiencing mild COVID-19 but without clear evidence of these sequelae can be regarded as having minimal additional perioperative risk. In this context, the relatively young person who suffered mild COVID-19 a year earlier, complains of exertional fatigue but admits to being sedentary and unfit, and has no objective evidence of cardiopulmonary disease or other organ dysfunction will likely raise little concern.

While the morbidity and mortality associated with severe COVID-19 has appropriately received considerable attention, most SARS-CoV-2 infections result in relatively mild, self-limited symptoms not requiring hospitalization. Nonetheless, some of these patients subsequently experience persistent fatigue and reduced exercise capacity that is not attributable to cardiopulmonary impairment diagnosed by conventional means3. Several mechanisms have been proposed including anaemia, deconditioning, and red blood cell abnormalities4. However, many of the studies describing these mechanisms were conducted in patients following hospitalization and/or within a few months of recovery.

A central focus of perioperative management has always been maintenance of systemic oxygen delivery (DO2) and tissue perfusion. Toward this end, research has defined how the fundamental relationships between DO2, tissue oxygen consumption (VO2), and oxygen extraction (EO2) shift from the intraoperative setting where VO2 tends to be reduced, to the postoperative period when VO2 increases5. Although a range of postoperative complications has been linked to suboptimal tissue DO26,  7, the incidence of these complications appears relatively low in relation to the documented incidence of perioperative hypoxaemia8,  9, particularly when considered in light of potential coincidence with other common factors such as anaemia, hypovolaemia, and transient hypotension. A contributing factor may be that, as with most physiological systems, evolutionary pressure has yielded compensatory mechanisms for reduced DO2 to many organs. Under most circumstances, when DO2 is low, VO2 is maintained by augmented EO2 to prevent tissue hypoxia10. This compensatory EO2 reserve persists until limits that vary among tissue beds are reached and VO2 becomes DO2-dependent. Ultimately, in the perioperative setting where alterations in regional VO2/DO2 balance occur with regularity it is probable that this EO2 reserve is working continuously ‘behind the scenes’ for organ protection.

But what if this seemingly occult protective mechanism is impaired? Clinical experience imparts heightened suspicion of tissue vulnerability in patients with defined end-organ impairment or risk factors for reduced functional reserve such as aging, smoking, diabetes mellitus, or hypertension. But how does this affect that relatively young person who admits to being sedentary and unfit but has no objective evidence of cardiopulmonary disease, and whose only other notable medical history is mild COVID-19 a year earlier? A recent report proposed the existence of a specific “long COVID phenotype” with exertional intolerance and dyspnoea despite normal pulmonary function11, raising the question of whether there is more to this patient than meets the eye.

Read the rest of this article HERE.

Source: Paul M. Heerdt, Ben Shelley, Inderjit Singh. Impaired systemic oxygen extraction long after mild COVID-19: potential perioperative implications. Published: December 27, 2021. DOI:https://doi.org/10.1016/j.bja.2021.12.036

Disturbances in sleep, circadian rhythms and daytime functioning in relation to coronavirus infection and Long-COVID – A multinational ICOSS study

Abstract:

This protocol paper describes the second survey produced by the International Covid Sleep Study (ICOSS) group with the aim to examine the associations between SARS-CoV-2 infection and sleep, sleepiness, and circadian problems as potential predisposing factors for more severe COVID-19 disease profile and for development of Long-COVID in the general population. The survey consists of 47 questions on sleep, daytime sleepiness, circadian rhythm, health, mental wellbeing, life habits, and socioeconomic situation before and during the pandemic, and conditional questions to those reporting having had coronavirus infection, being vaccinated, or suffering from particular sleep symptoms or sleep disorders. Surveys will be administered online between May and November 2021 in Austria, Brazil, Bulgaria, Canada, China, Croatia, Finland, France, Germany, Israel, Italy, Japan, Norway, Portugal, Sweden and USA. Data collected by the survey will give valuable information on the open questions regarding COVID-19 disease risk factors, symptomatology and evolution of Long-COVID, and on other long-term consequences related to the pandemic.

Source: Merikanto I, Dauvilliers Y, Chung F, Holzinger B, De Gennaro L, Wing YK, Korman M, Partinen M; 2nd ICOSS members. Disturbances in sleep, circadian rhythms and daytime functioning in relation to coronavirus infection and Long-COVID – A multinational ICOSS study. J Sleep Res. 2021 Dec 28:e13542. doi: 10.1111/jsr.13542. Epub ahead of print. PMID: 34964184. https://pubmed.ncbi.nlm.nih.gov/34964184/

Multisystem Involvement in Post-acute Sequelae of COVID-19 (PASC)

Abstract:

Objective: To describe cerebrovascular, neuropathic and autonomic features of post-acute sequelae of COVID-19 (PASC).

Methods: This retrospective study evaluated consecutive patients with chronic fatigue, brain fog and orthostatic intolerance consistent with PASC. Controls included postural tachycardia syndrome patients (POTS) and healthy participants. Analyzed data included surveys and autonomic (Valsalva maneuver, deep breathing, sudomotor and tilt tests), cerebrovascular (cerebral blood flow velocity (CBFv) monitoring in middle cerebral artery), respiratory (capnography monitoring) and neuropathic (skin biopsies for assessment of small fiber neuropathy) testing and inflammatory/autoimmune markers.

Results: Nine PASC patients were evaluated 0.7±0.3 years after a mild COVID-19 infection, treated as home observations. Autonomic, pain, brain fog, fatigue and dyspnea surveys were abnormal in PASC and POTS (n=10), compared to controls (n=15). Tilt table test reproduced the majority of PASC symptoms. Orthostatic CBFv declined in PASC (-20.0±13.4%) and POTS (-20.3±15.1%), compared to controls (-3.0±7.5%,p=0.001) and was independent of end-tidal carbon dioxide in PASC, but caused by hyperventilation in POTS. Reduced orthostatic CBFv in PASC included both subjects without (n=6) and with (n=3) orthostatic tachycardia. Dysautonomia was frequent (100% in both PASC and POTS) but was milder in PASC (p=0.013). PASC and POTS cohorts diverged in frequency of small fiber neuropathy (89% vs. 60%) but not in inflammatory markers (67% vs. 70%). Supine and orthostatic hypocapnia was observed in PASC.

Interpretation: PASC following mild COVID-19 infection is associated with multisystem involvement including: 1) cerebrovascular dysregulation with persistent cerebral arteriolar vasoconstriction; 2) small fiber neuropathy and related dysautonomia; 3) respiratory dysregulation; 4) chronic inflammation.

Source: Novak P, Mukerji SS, Alabsi HS, Systrom D, Marciano SP, Felsenstein D, Mullally WJ, Pilgrim DM. Multisystem Involvement in Post-acute Sequelae of COVID-19 (PASC). Ann Neurol. 2021 Dec 24. doi: 10.1002/ana.26286. Epub ahead of print. PMID: 34952975. https://pubmed.ncbi.nlm.nih.gov/34952975/

Year-long COVID-19 infection reveals within-host evolution of SARS-CoV-2 in a patient with B cell depletion

Abstract:

B-cell depleting therapies may lead to prolonged disease and viral shedding in individuals infected with SARS-CoV-2 and this viral persistence raises concern for viral evolution. We report on the sequencing of early and late samples from a 335-day infection in an immunocompromised patient. The virus accumulated a unique deletion in the amino-terminal domain of the spike protein, and complete deletion of ORF7b and ORF8, the first report of its kind in an immunocompromised patient. Overall, the unique viral mutations found in this study highlight the importance of analyzing viral evolution in protracted SARS-CoV-2 infection, especially in immunosuppressed hosts.

Source: Nussenblatt V, Roder AE, Das S, de Wit E, Youn JH, Banakis S, Mushegian A, Mederos C, Wang W, Chung M, Pérez-Pérez L, Palmore T, Brudno JN, Kochenderfer JN, Ghedin E. Year-long COVID-19 infection reveals within-host evolution of SARS-CoV-2 in a patient with B cell depletion. J Infect Dis. 2021 Dec 23:jiab622. doi: 10.1093/infdis/jiab622. Epub ahead of print. PMID: 34940844. https://pubmed.ncbi.nlm.nih.gov/34940844/