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1.
Front Immunol ; 12: 697622, 2021.
Article in English | MEDLINE | ID: covidwho-1518482

ABSTRACT

Objectives: The longitudinal and systematic evaluation of immunity in coronavirus disease 2019 (COVID-19) patients is rarely reported. Methods: Parameters involved in innate, adaptive, and humoral immunity were continuously monitored in COVID-19 patients from onset of illness until 45 days after symptom onset. Results: This study enrolled 27 mild, 47 severe, and 46 deceased COVID-19 patients. Generally, deceased patients demonstrated a gradual increase of neutrophils and IL-6 but a decrease of lymphocytes and platelets after the onset of illness. Specifically, sustained low numbers of CD8+ T cells, NK cells, and dendritic cells were noted in deceased patients, while these cells gradually restored in mild and severe patients. Furthermore, deceased patients displayed a rapid increase of HLA-DR expression on CD4+ T cells in the early phase, but with a low level of overall CD45RO and HLA-DR expressions on CD4+ and CD8+ T cells, respectively. Notably, in the early phase, deceased patients showed a lower level of plasma cells and antigen-specific IgG, but higher expansion of CD16+CD14+ proinflammatory monocytes and HLA-DR-CD14+ monocytic-myeloid-derived suppressor cells (M-MDSCs) than mild or severe patients. Among these immunological parameters, M-MDSCs showed the best performance in predicting COVID-19 mortality, when using a cutoff value of ≥10%. Cluster analysis found a typical immunological pattern in deceased patients on day 9 after onset, which was characterized as the increase of inflammatory markers (M-MDSCs, neutrophils, CD16+CD14+ monocytes, and IL-6) but a decrease of host immunity markers. Conclusions: This study systemically characterizes the kinetics of immunity of COVID-19, highlighting the importance of immunity in patient prognosis.


Subject(s)
COVID-19/immunology , SARS-CoV-2 , Adaptive Immunity , Aged , Aged, 80 and over , Antibodies, Viral/blood , B-Lymphocytes/immunology , COVID-19/blood , COVID-19/classification , COVID-19/physiopathology , Cytokines/blood , Dendritic Cells/immunology , Female , Humans , Immunity, Innate , Immunoglobulin G/blood , Killer Cells, Natural/immunology , Lymphocyte Count , Male , Middle Aged , SARS-CoV-2/immunology , Severity of Illness Index , T-Lymphocytes/immunology
2.
mBio ; : e0297521, 2021 Nov 16.
Article in English | MEDLINE | ID: covidwho-1518123

ABSTRACT

Several severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants have arisen that exhibit increased viral transmissibility and partial evasion of immunity induced by natural infection and vaccination. To address the specific antibody targets that were affected by recent viral variants, we generated 43 monoclonal antibodies (mAbs) from 10 convalescent donors that bound three distinct domains of the SARS-CoV-2 spike. Viral variants harboring mutations at K417, E484, and N501 could escape most of the highly potent antibodies against the receptor binding domain (RBD). Despite this, we identified 12 neutralizing mAbs against three distinct regions of the spike protein that neutralize SARS-CoV-2 and variants of concern (VOCs), including B.1.1.7 (alpha), P.1 (gamma), and B.1.617.2 (delta). Notably, antibodies targeting distinct epitopes could neutralize discrete variants, suggesting that different variants may have evolved to disrupt the binding of particular neutralizing antibody classes. These results underscore that humans exposed to the first pandemic wave of prototype SARS-CoV-2 possess neutralizing antibodies against current variants and that it is critical to induce antibodies targeting multiple distinct epitopes of the spike that can neutralize emerging variants of concern. IMPORTANCE We describe the binding and neutralization properties of a new set of human monoclonal antibodies derived from memory B cells of 10 coronavirus disease 2019 (COVID-19) convalescent donors in the first pandemic wave of prototype SARS-CoV-2. There were 12 antibodies targeting distinct epitopes on spike, including two sites on the RBD and one on the N-terminal domain (NTD), that displayed cross-neutralization of VOCs, for which distinct antibody targets could neutralize discrete variants. This work underlines that natural infection by SARS-CoV-2 induces effective cross-neutralization against only some VOCs and supports the need for COVID-19 vaccination for robust induction of neutralizing antibodies targeting multiple epitopes of the spike protein to combat the current SARS-CoV-2 VOCs and any others that might emerge in the future.

3.
J Mol Cell Biol ; 2021 Oct 23.
Article in English | MEDLINE | ID: covidwho-1483467

ABSTRACT

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, has become a global public health crisis. Some patients who have recovered from COVID-19 subsequently test positive again for SARS-CoV-2 RNA after discharge from hospital. How such retest-positive (RTP) patients become infected again is not known. In this study, 30 RTP patients, 20 convalescent patients, and 20 healthy controls were enrolled for the analysis of immunological characteristics of their peripheral-blood mononuclear cells. We found that absolute numbers of CD4+ T cells, CD8+ T cells, and natural killer cells were not substantially decreased in RTP patients, but the expression of activation markers on these cells was significantly reduced. The percentage of granzyme B-producing T cells was also lower in RTP patients than in convalescent patients. Through transcriptome sequencing, we demonstrated that high expression of inhibitor of differentiation 1 (ID1) and low expression of interferon-induced transmembrane protein 10 (IFITM10) were associated with insufficient activation of immune cells and the occurrence of RTP. These findings provide insight into the impaired immune function associated with COVID-19 and the pathogenesis of RTP, which may contribute to a better understanding of the mechanisms underlying RTP.

4.
Drug Dev Ind Pharm ; : 1-22, 2021 Oct 04.
Article in English | MEDLINE | ID: covidwho-1450327

ABSTRACT

PURPOSE: Through the method of network pharmacology, the active components and targets of Shenqi wan (SQW) were excavated, the relationship with COVID-19 was discussed, and the possible mechanism of SQW in the treatment of COVID-19 was revealed from the aspects of multi-components, multi-targets, and multi-pathways. METHODS: Firstly, the active components of SQW were screened from TCMSP and the 2020 edition of Chinese Pharmacopoeia, and the related targets of the components were obtained. Then the disease targets related to COVID-19 were screened from GeneCards and OMIM. Venny was used to map the relationship between component-target and disease-target, and String was used to analyzing the interaction of common targets. The network was constructed and analyzed by Cytoscape, the function of GO and KEGG genes was enriched by Metascape, and the molecular docking was verified by CB-Dock. RESULTS: Finally, 45 active components of SQW were obtained, and 72 potential targets were related to COVID-19, ACE2, IL6, NOS3, and CRP may be the key targets. GO enrichment of 1715 projects, such as lipopolysaccharide stress response, active oxygen metabolism, positive regulation of cell migration, and other GO enrichment. 136 KEGG pathways were obtained, TNF signaling pathway, IL-17 signaling pathway, HIF-1 signaling pathway. Molecular docking showed that kaempferol, quercetin, luteolin, astragaloside, calyx isoflavone glucoside, matrine, and other COVID-19-related targets such as ACE2, 3CLpro, PLpro, PTGS2 have good binding ability. CONCLUSION: According to the above results, it is suggested that SQW may play a role in the treatment of COVID-19 by directly or indirectly combining kaempferol, quercetin, and luteolin with ACE2, 3CLpro, PLpro, and PTGS2 to regulate multiple biological functions and signaling pathways.

5.
Drug Evaluation Research ; 43(9):1685-1692, 2020.
Article in Chinese | CAB Abstracts | ID: covidwho-1395260

ABSTRACT

Objective: Analyzed the prescriptions of traditional Chinese medicine (TCM) for patients diagnosed with Novel Coronavirus Pneumonia (COVID-19), and the medication patterns were statistically analyzed to provide reference for the treatment of COVID-19.

7.
EXCLI J ; 20: 894-906, 2021.
Article in English | MEDLINE | ID: covidwho-1261489

ABSTRACT

Sleep is believed to benefit the host defense against pathogens. We aimed to investigate the association of sleep quality with clinical outcomes among hospitalized patients with COVID-19. We conducted a prospective cohort study in 205 adult hospitalized patients with diagnosed moderate COVID-19, with follow-up until hospital discharge or death. Pittsburgh Sleep Quality Index (PSQI) assessed sleep quality before and after infection. The primary outcome was the incidence of severe or critical pneumonia, and the secondary outcomes were duration of hospital stay and laboratory measurements during the follow up. Among the 205 included hospitalized patients, 185 (90.2 %) experienced poorer sleep quality after infection than before according to the PSQI score, and 25 (12.2 %) developed severe or critical pneumonia during follow-up. In Cox regression models, the adjusted hazard ratio of developing severe or critical pneumonia associated with each 1 score increment in the PSQI score before and after infection was 1.23 (95% CI: 1.09, 1.39) and 1.35 (95 % CI: 1.08, 1.67), respectively. Poorer sleep quality was also significantly associated with a prolonged hospital stay and more serious dysregulations in immune system indicated by several laboratory markers. Poorer sleep quality, either in the daily time or after infection with SARS-CoV-2, was associated with worse clinical outcomes. These findings highlight the importance of good sleep in confronting the emerging pandemic of COVID-19.

8.
Immunity ; 54(6): 1290-1303.e7, 2021 06 08.
Article in English | MEDLINE | ID: covidwho-1237724

ABSTRACT

Dissecting the evolution of memory B cells (MBCs) against SARS-CoV-2 is critical for understanding antibody recall upon secondary exposure. Here, we used single-cell sequencing to profile SARS-CoV-2-reactive B cells in 38 COVID-19 patients. Using oligo-tagged antigen baits, we isolated B cells specific to the SARS-CoV-2 spike, nucleoprotein (NP), open reading frame 8 (ORF8), and endemic human coronavirus (HCoV) spike proteins. SARS-CoV-2 spike-specific cells were enriched in the memory compartment of acutely infected and convalescent patients several months post symptom onset. With severe acute infection, substantial populations of endemic HCoV-reactive antibody-secreting cells were identified and possessed highly mutated variable genes, signifying preexisting immunity. Finally, MBCs exhibited pronounced maturation to NP and ORF8 over time, especially in older patients. Monoclonal antibodies against these targets were non-neutralizing and non-protective in vivo. These findings reveal antibody adaptation to non-neutralizing intracellular antigens during infection, emphasizing the importance of vaccination for inducing neutralizing spike-specific MBCs.


Subject(s)
Antibodies, Viral/immunology , Antibody Formation/immunology , B-Lymphocytes/immunology , COVID-19/immunology , Host-Pathogen Interactions/immunology , Immunodominant Epitopes/immunology , SARS-CoV-2/immunology , Antibodies, Neutralizing/immunology , Antibody Formation/genetics , B-Lymphocytes/metabolism , Computational Biology/methods , Cross Reactions/immunology , Epitope Mapping , Female , Gene Expression Profiling , High-Throughput Nucleotide Sequencing , Host-Pathogen Interactions/genetics , Humans , Immunodominant Epitopes/genetics , Immunologic Memory , Male , Neutralization Tests , Single-Cell Analysis/methods , Spike Glycoprotein, Coronavirus/immunology , Transcriptome
9.
Signal Transduct Target Ther ; 6(1): 181, 2021 05 10.
Article in English | MEDLINE | ID: covidwho-1223081

ABSTRACT

Over 40% of the coronavirus disease 2019 (COVID-19) COVID-19 patients were asymptomatically infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the immune responses of these asymptomatic individuals is a critical factor for developing the strategy to contain the COVID-19 pandemic. Here, we determined the viral dynamics and antibody responses among 143 asymptomatic individuals identified in a massive screening of more than 5 million people in eight districts of Wuhan in May 2020. Asymptomatic individuals were admitted to the government-designated centralized sites in accordance with policy. The incidence rate of asymptomatic infection is ~2.92/100,000. These individuals had low viral copy numbers (peaked at 315 copies/mL) and short-lived antibody responses with the estimated diminish time of 69 days. The antibody responses in individuals with persistent SARS-CoV-2 infection is much longer with the estimated diminish time of 257 days. These results imply that the immune responses in the asymptomatic individuals are not potent enough for preventing SARS-CoV-2 re-infection, which has recently been reported in recovered COVID-19 patients. This casts doubt on the efficacy of forming "herd-immunity" through natural SARS-CoV-2 infection and urges for the development of safe and effective vaccines.


Subject(s)
Antibodies, Viral/immunology , Asymptomatic Infections/epidemiology , COVID-19/immunology , Immunity/immunology , Aged , Antibodies, Viral/blood , Antibodies, Viral/genetics , COVID-19/blood , COVID-19/physiopathology , COVID-19/virology , China/epidemiology , Female , Humans , Male , Middle Aged , Pandemics , SARS-CoV-2/immunology , SARS-CoV-2/pathogenicity
10.
Turk J Gastroenterol ; 32(2): 148-154, 2021 02.
Article in English | MEDLINE | ID: covidwho-1220242

ABSTRACT

BACKGROUND: Patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes coronavirus disease 2019 (COVID-19), have fever, dry cough, dyspnea, and fatigue. The disease has now become a global pandemic. The purpose of this study was to explore the relationship between COVID-19 and gastrointestinal (GI) symptoms. METHODS: We collected and analyzed data on patients with laboratory-confirmed COVID-19 by high-throughput sequencing or reverse transcription-polymerase chain reaction. We reviewed electronic medical records of 405 hospitalized COVID-19 patients in the Third Hospital of Wuhan. RESULTS: Among the 405 confirmed patients, 210 had no GI symptoms, 195 had GI symptoms, and the first symptom of 155 patients was GI. The prevalence of vascular and digestive diseases in the group with GI symptoms was significantly higher than in the group without GI symptoms. In patients with GI symptoms, the proportion with fever, cough, dysphoria, chest tightness, poor appetite, chest pain, and pharyngeal pain was significantly higher than in those without GI symptoms. There was no significant difference in imaging between the 2 groups. In patients with GI symptoms, the proportion with increased procalcitonin (PCT) level and decreased lymphocyte count was significantly higher than in those without GI symptoms. CONCLUSION: COVID-19 patients with GI symptoms had significantly more vascular and digestive system diseases and were more likely to have clinical manifestations of fever, cough, poor appetite, chest tightness, chest pain, insomnia, and pharyngeal pain. There were more patients with diarrhea, nausea, and vomiting. Patients with GI symptoms were more likely to have increased PCT and decreased lymphocyte count.


Subject(s)
COVID-19/complications , Gastrointestinal Diseases/epidemiology , Gastrointestinal Diseases/virology , SARS-CoV-2 , Adult , Aged , COVID-19/blood , COVID-19/virology , China/epidemiology , Diarrhea/blood , Diarrhea/epidemiology , Diarrhea/virology , Female , Humans , Lymphocyte Count , Male , Middle Aged , Nausea/blood , Nausea/epidemiology , Nausea/virology , Procalcitonin/blood , Vomiting/blood , Vomiting/epidemiology , Vomiting/virology
12.
mBio ; 12(1)2021 01 19.
Article in English | MEDLINE | ID: covidwho-1038406

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is currently causing a global pandemic. The antigen specificity of the antibody response mounted against this novel virus is not understood in detail. Here, we report that subjects with a more severe SARS-CoV-2 infection exhibit a larger antibody response against the spike and nucleocapsid protein and epitope spreading to subdominant viral antigens, such as open reading frame 8 and nonstructural proteins. Subjects with a greater antibody response mounted a larger memory B cell response against the spike, but not the nucleocapsid protein. Additionally, we revealed that antibodies against the spike are still capable of binding the D614G spike mutant and cross-react with the SARS-CoV-1 receptor binding domain. Together, this study reveals that subjects with a more severe SARS-CoV-2 infection exhibit a greater overall antibody response to the spike and nucleocapsid protein and a larger memory B cell response against the spike.IMPORTANCE With the ongoing pandemic, it is critical to understand how natural immunity against SARS-CoV-2 and COVID-19 develops. We have identified that subjects with more severe COVID-19 disease mount a more robust and neutralizing antibody response against SARS-CoV-2 spike protein. Subjects who mounted a larger response against the spike also mounted antibody responses against other viral antigens, including the nucleocapsid protein and ORF8. Additionally, this study reveals that subjects with more severe disease mount a larger memory B cell response against the spike. These data suggest that subjects with more severe COVID-19 disease are likely better protected from reinfection with SARS-CoV-2.


Subject(s)
COVID-19/immunology , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , Adult , Antibodies, Neutralizing/immunology , Antibodies, Viral/blood , Antibodies, Viral/immunology , Antigens, Viral/immunology , B-Lymphocytes/immunology , COVID-19/blood , COVID-19/virology , Coronavirus Nucleocapsid Proteins/immunology , Cross Reactions , Epitopes/immunology , Female , Humans , Immunity, Humoral/immunology , Male , Middle Aged , Phosphoproteins/immunology
13.
Signal Transduct Target Ther ; 5(1): 283, 2020 12 04.
Article in English | MEDLINE | ID: covidwho-957563

ABSTRACT

In face of the everlasting battle toward COVID-19 and the rapid evolution of SARS-CoV-2, no specific and effective drugs for treating this disease have been reported until today. Angiotensin-converting enzyme 2 (ACE2), a receptor of SARS-CoV-2, mediates the virus infection by binding to spike protein. Although ACE2 is expressed in the lung, kidney, and intestine, its expressing levels are rather low, especially in the lung. Considering the great infectivity of COVID-19, we speculate that SARS-CoV-2 may depend on other routes to facilitate its infection. Here, we first discover an interaction between host cell receptor CD147 and SARS-CoV-2 spike protein. The loss of CD147 or blocking CD147 in Vero E6 and BEAS-2B cell lines by anti-CD147 antibody, Meplazumab, inhibits SARS-CoV-2 amplification. Expression of human CD147 allows virus entry into non-susceptible BHK-21 cells, which can be neutralized by CD147 extracellular fragment. Viral loads are detectable in the lungs of human CD147 (hCD147) mice infected with SARS-CoV-2, but not in those of virus-infected wild type mice. Interestingly, virions are observed in lymphocytes of lung tissue from a COVID-19 patient. Human T cells with a property of ACE2 natural deficiency can be infected with SARS-CoV-2 pseudovirus in a dose-dependent manner, which is specifically inhibited by Meplazumab. Furthermore, CD147 mediates virus entering host cells by endocytosis. Together, our study reveals a novel virus entry route, CD147-spike protein, which provides an important target for developing specific and effective drug against COVID-19.


Subject(s)
Basigin/genetics , COVID-19/genetics , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , Animals , Basigin/immunology , COVID-19/immunology , COVID-19/pathology , COVID-19/virology , Host-Pathogen Interactions/immunology , Humans , Lung/immunology , Lung/pathology , Lung/virology , Mice , Pandemics , Protein Binding/immunology , Protein Domains/genetics , Protein Domains/immunology , SARS-CoV-2/pathogenicity , Spike Glycoprotein, Coronavirus/genetics , Virus Internalization
14.
Res Sq ; 2020 Sep 25.
Article in English | MEDLINE | ID: covidwho-807694

ABSTRACT

Discovery of durable memory B cell (MBC) subsets against neutralizing viral epitopes is critical for determining immune correlates of protection from SARS-CoV-2 infection. Here, we identified functionally distinct SARS-CoV-2-reactive B cell subsets by profiling the repertoire of convalescent COVID-19 patients using a high-throughput B cell sorting and sequencing platform. Utilizing barcoded SARS-CoV-2 antigen baits, we isolated thousands of B cells that segregated into discrete functional subsets specific for the spike, nucleocapsid protein (NP), and open reading frame (ORF) proteins 7a and 8. Spike-specific B cells were enriched in canonical MBC clusters, and monoclonal antibodies (mAbs) from these cells were potently neutralizing. By contrast, B cells specific to ORF8 and NP were enriched in naïve and innate-like clusters, and mAbs against these targets were exclusively non-neutralizing. Finally, we identified that B cell specificity, subset distribution, and affinity maturation were impacted by clinical features such as age, sex, and symptom duration. Together, our data provide a comprehensive tool for evaluating B cell immunity to SARS-CoV-2 infection or vaccination and highlight the complexity of the human B cell response to SARS-CoV-2.

17.
JCI Insight ; 5(10)2020 05 21.
Article in English | MEDLINE | ID: covidwho-118074

ABSTRACT

BACKGROUNDThe coronavirus disease 2019 (COVID-19), infected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has caused a severe outbreak throughout the world. The host immunity of COVID-19 patients is unknown.METHODSThe routine laboratory tests and host immunity in COVID-19 patients with different severity of illness were compared after patient admission.RESULTSA total of 65 SARS-CoV-2-positive patients were classified as having mild (n = 30), severe (n = 20), and extremely severe (n = 15) illness. Many routine laboratory tests, such as ferritin, lactate dehydrogenase, and D-dimer, were increased in severe and extremely severe patients. The absolute numbers of CD4+ T cells, CD8+ T cells, and B cells were gradually decreased with increased severity of illness. The activation markers such as HLA-DR and CD45RO expressed on CD4+ and CD8+ T cells were increased in severe and extremely severe patients compared with mild patients. The costimulatory molecule CD28 had opposite results. The percentage of natural Tregs was decreased in extremely severe patients. The percentage of IFN-γ-producing CD8+ T cells was increased in both severe and extremely severe patients compared with mild patients. The percentage of IFN-γ-producing CD4+ T cells was increased in extremely severe patients. IL-2R, IL-6, and IL-10 were all increased in extremely severe patients. The activation of DC and B cells was decreased in extremely severe patients.CONCLUSIONThe number and function of T cells are inconsistent in COVID-19 patients. The hyperfunction of CD4+ and CD8+ T cells is associated with the pathogenesis of extremely severe SARS-CoV-2 infection.FUNDINGThis work was funded by the National Mega Project on Major Infectious Disease Prevention (2017ZX10103005-007) and the Fundamental Research Funds for the Central Universities (2019kfyRCPY098).


Subject(s)
Coronavirus Infections/immunology , Coronavirus Infections/physiopathology , Pneumonia, Viral/immunology , Pneumonia, Viral/physiopathology , Betacoronavirus , CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , COVID-19 , Cytokines/metabolism , Diagnostic Tests, Routine , Female , Humans , Immunity , Lymphocyte Count , Male , Middle Aged , Pandemics , SARS-CoV-2 , Severity of Illness Index , T-Lymphocytes/immunology
18.
J Med Virol ; 92(9): 1572-1579, 2020 09.
Article in English | MEDLINE | ID: covidwho-23618

ABSTRACT

Coronavirus disease 2019 (COVID-19) broke out in Wuhan, Hubei, China in December 2019. Tens thousands of people have been infected with the disease. Our aim was to distinguish severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-positive patients from SARS-CoV-2-negative patients. We retrospectively compared the data of COVID-19 patients with those of suspected and confirmed SARS-CoV-2-negative patients (control patients). There were 78 COVID-19 patients and 26 control patients, whose median ages were significantly different (P = .001). The percentage of COVID-19 patients admitting exposure to Wuhan was obviously higher than that of control patients (X2 = 29.130; P < .001). Fever and cough appeared more frequently in COVID-19 patients than in the control patients. The routine blood workup parameters of COVID-19 patients did not change much and their mean counts were in the normal range. There were 38.5% of control patients had higher procalcitonin (PCT) levels than 0.5 ng/mL, which was significantly higher than that percentage of COVID-19 patients (X2 = 22.636; P < .05), and COVID-19 patients were also more likely to have decreased or normal urea and creatinine levels than control patients (X2 = 24.930, 8.480; P < .05).Younger age, exposure to Wuhan, fever, cough, and slight changes in routine blood workup parameters, urea and creatinine were important features discriminating COVID-19 from control patients. Slightly increased, but far less than 0.5 ng/mL, PCT levels also differentiated COVID-19 patients from control patients.


Subject(s)
COVID-19/diagnosis , COVID-19/virology , Pneumonia, Viral/diagnosis , SARS-CoV-2 , Adolescent , Adult , Aged , Biomarkers , COVID-19/complications , Diagnosis, Differential , Female , Humans , Male , Middle Aged , Patient Outcome Assessment , Pneumonia, Viral/etiology , Retrospective Studies , Symptom Assessment , Tomography, X-Ray Computed , Young Adult
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