Project description:Post-acute sequelae of COVID-19 (PASC) represent an emerging global crisis. However, quantifiable risk-factors for PASC and their biological associations are poorly resolved. We executed a deep multi-omic, longitudinal investigation of 309 COVID-19 patients from initial diagnosis to convalescence (2-3 months later), integrated with clinical data, and patient-reported symptoms. We resolved four PASC-anticipating risk factors at the time of initial COVID-19 diagnosis: type 2 diabetes, SARS-CoV-2 RNAemia, Epstein-Barr virus viremia, and specific autoantibodies. In patients with gastrointestinal PASC, SARS-CoV-2-specific and CMV-specific CD8+ T cells exhibited unique dynamics during recovery from COVID-19. Analysis of symptom-associated immunological signatures revealed coordinated immunity polarization into four endotypes exhibiting divergent acute severity and PASC. We find that immunological associations between PASC factors diminish over time leading to distinct convalescent immune states. Detectability of most PASC factors at COVID-19 diagnosis emphasizes the importance of early disease measurements for understanding emergent chronic conditions and suggests PASC treatment strategies.
Project description:Most patients infected with SARS-CoV-2 are asymptomatic or mildly symptomatic. However, the early and late antibody kinetics, and the association between antibody levels, clinical symptoms, and disease phase in these patients have not yet been fully defined. Confirmed SARS-CoV-2 patients and their household contacts were evaluated over a period four months. The evaluation procedure included symptom monitoring, viral load and serology analysis every ten days. A total of 1334 serum samples were collected from 135 patients and analyzed using three assays for IgG-N, IgG-S and IgM antibodies. Of the study participants, 97% were seropositive during the study, and two distinct clusters were identified. These clusters were significantly different in their inflammatory related symptoms. Peak IgG-S was 40.0 AU/ml for the non-inflammatory cluster and 71.5 AU/ml for the inflammatory cluster (P = 0.006), whereas IgG-N peaks were 4.3 and 5.87 (P = 0.023) respectively. Finally, a decision tree model was designed to predict the disease phase based on the serological titer levels, and had an overall accuracy of 80.7%. The specific profile of seroconversion and decay of serum antibodies can be used to predict the time-course from the acute infection.
Project description:We perform shotgun transcriptome sequencing of human RNA obtained from nasopharyngeal swabs of patients with COVID-19, and identify a molecular signature associated with disease severity
Project description:Although a substantial proportion of severe COVID-19 pneumonia survivors exhibit long-term pulmonary sequalae, the underlying mechanisms or associated local and systemic immune correlates are not known. Here, we have performed high dimensional characterization of the pathophysiological and immune traits of aged COVID-19 convalescents, and correlated the local and systemic immune profiles with pulmonary function and lung imaging. In this cohort of aged COVID-19 convalescents, chronic lung impairment was accompanied by persistent systemic inflammation and respiratory immune alterations. Detailed evaluation of the lung immune compartment revealed dysregulated respiratory CD8+ T cell responses that likely underlie the impaired lung function following acute COVID-19 during aging. Single cell transcriptomic analysis identified the potential pathogenic subsets of respiratory CD8+ T cells causing persistent tissue conditions following COVID-19. Our results have revealed key pathophysiological and immune traits that support the development of lung sequelae following SARS-CoV2 pneumonia during aging, with implications for the treatment of chronic COVID-19 symptoms.
Project description:ObjectivesDetailed knowledge on the prevalence of asymptomatic cases of coronavirus disease 2019 (COVID-19) and the clinical characteristics of mild COVID-19 is essential for effective control of the COVID-19 pandemic. We determined the prevalence of asymptomatic cases of COVID-19 and characterized the symptoms of patients with mild COVID-19.MethodsStudy participants were recruited from a community facility designated for the isolation of patients without moderate-to-severe symptoms of COVID-19 in South Korea. The prevalence of asymptomatic patients at admission and the detailed symptoms of mild COVID-19 were evaluated through a questionnaire-based survey. Diagnosis of COVID-19 was confirmed by real-time RT-PCR.ResultsOf the 213 individuals with COVID-19, 41 (19.2%) were asymptomatic until admission. Among the remaining patients with mild COVID-19, the most common symptom was cough (40.1%; 69/172), followed by hyposmia (39.5%; 68/172) and sputum (39.5%; 68/172). Of the 68 individuals with hyposmia, 61 (90%) had accompanying symptoms such as hypogeusia, nasal congestion or rhinorrhoea. Fever (>37.5°C) was only observed in 20 (11.6%) individuals.ConclusionsAs much as one-fifth of individuals with COVID-19 remained asymptomatic from exposure to admission. Hyposmia was quite frequent among individuals with mild COVID-19, but fever was not. Social distancing should be strongly implemented to prevent disease transmission from asymptomatic individuals or those with mild and inconspicuous symptoms.
Project description:It is important to evaluate the durability of the protective immune response elicited by primary infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Here, we systematically evaluated the SARS-CoV-2-specific memory B cell and T cell responses in healthy controls and individuals recovered from asymptomatic or symptomatic infection approximately 6 months prior. Comparatively low frequencies of memory B cells specific for the receptor-binding domain (RBD) of spike glycoprotein (S) persisted in the peripheral blood of individuals who recovered from infection (median 0.62%, interquartile range 0.48-0.69). The SARS-CoV-2 RBD-specific memory B cell response was detected in 2 of 13 individuals who recovered from asymptomatic infection and 10 of 20 individuals who recovered from symptomatic infection. T cell responses induced by S, membrane (M), and nucleocapsid (N) peptide libraries from SARS-CoV-2 were observed in individuals recovered from coronavirus disease 2019 (COVID-19), and cross-reactive T cell responses to SARS-CoV-2 were also detected in healthy controls.
Project description:BackgroundIt is expected that GPs are increasingly confronted with a large group of patients with symptoms persisting three weeks after initial symptoms of a mild (managed in the outpatient setting) COVID-19 infection. Currently, research on these persistent symptoms mainly focuses on patients with severe infections (managed in an inpatient setting) whereas patients with mild disease are rarely studied.ObjectiveThe main objective of this systematic review was to create an overview of the nature and frequency of persistent symptoms experienced by patients after mild COVID-19 infection.MethodsSystematic literature searches were performed in Pubmed, Embase and PsychINFO on 2 February 2021. Quantitative studies, qualitative studies, clinical lessons and case reports were considered eligible designs.ResultsIn total, nine articles were included in this literature review. The frequency of persistent symptoms in patients after mild COVID-19 infection ranged between 10% and 35%. Symptoms persisting after a mild COVID-19 infection can be distinguished into physical, mental and social symptoms. Fatigue was the most frequently described persistent symptom. Other frequently occurring persistent symptoms were dyspnoea, cough, chest pain, headache, decreased mental and cognitive status and olfactory dysfunction. In addition, it was found that persisting symptoms after a mild COVID-19 infection can have major consequences for work and daily functioning.ConclusionThere is already some evidence that symptoms of mild COVID-19 persist after 3 weeks in a third of patients. However, there is a lack of data about symptoms persisting after 3 months (long-COVID). More research is needed to help GPs in managing long-COVID.
Project description:The immune responses and mechanisms limiting symptom progression in asymptomatic cases of SARS-CoV-2 infection remain unclear. We comprehensively characterized transcriptomic profiles, cytokine responses, neutralization capacity of antibodies and cellular immune phenotypes of asymptomatic patients with acute SARS-CoV-2 infection to identify potential protective mechanisms. Compared to symptomatic patients, asymptomatic patients had higher counts of mature neutrophils and lower proportion of CD169+ expressing monocytes in the peripheral blood. Systemic levels of pro-inflammatory cytokines were also lower in asymptomatic patients, accompanied by milder pro-inflammatory gene signatures. Mechanistically, a more robust systemic Th2 cell signature with a higher level of virus-specific Th17 cells and a weaker yet sufficient neutralizing antibody profile against SARS-CoV-2 was observed in asymptomatic patients. In addition, asymptomatic COVID-19 patients had higher systemic levels of growth factors that are associated with cellular repair. Together, asymptomatic patients mount less pro-inflammatory and more protective immune responses against SARS-CoV-2 indicative of disease tolerance. Insights from this study highlight key immune pathways that could serve as therapeutic targets to prevent disease progression in COVID-19.
Project description:We performed longitudinal plasma proteomics analysis and determined absolute protein levels in a Canadian cohort (n=74) at admission day to hospital for acute COVID-19 and at 3 and 6 months after diagnosis of acute COVID-19. We measured plasma protein on a triple quadrupole mass spectrometer operated in multiple reaction monitoring mode and used internal standards to deduce protein absolute concentrations. We used a validated panel of 269 surrogate heavy labeled peptides. We also measured % predicted forced vital capacity (FVC, %) and diffusing capacity of the lungs for carbon monoxide (DLCO, %) by routine pulmonary function testing. We did functional enrichment and pathway analyses and determined proteins that were increased or decreased from hospital admission to 3-months and 6-months, compared females to males and determined associations of proteins with FVC% and DLCO%.