C, et al. Clinical characteristics of 138 hospitalized patients with 2019 novel coronavirus-infected pneumonia in Wuhan, China. JAMA.

No abstract

No abstract

Long-term SARS-CoV-2 shedding was observed from the upper respiratory tract of a female immunocompromised patient with chronic lymphocytic leukemia and acquired hypogammaglobulinemia. Shedding of infectious SARS-CoV-2 was observed up to 70 days, and genomic and subgenomic RNA up to 105 days past initial diagnosis. The infection was not cleared after a first treatment with convalescent plasma, suggesting limited impact on SARS-CoV-2 in the upper respiratory tract within this patient. Several weeks after a second convalescent plasma transfusion, SARS-CoV-2 RNA was no longer detected. We observed marked within-host genomic evolution of SARS-CoV-2, with continuous turnover of dominant viral variants. However, replication kinetics in Vero E6 cells and primary human alveolar epithelial tissues were not affected. Our data indicate that certain immunocompromised patients may shed infectious virus for longer durations than previously recognized. Detection of subgenomic RNA is recommended in persistently SARS-CoV-2 positive individuals as a proxy for shedding of infectious virus.

Background Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the cause of coronavirus disease 2019 (COVID-19), is associated with respiratory-related disease and death. Assays to detect virus-specific antibodies are important to understand the prevalence of infection and the course of the immune response. Methods Quantitative measurements of plasma or serum antibodies to the nucleocapsid and spike proteins were analyzed using luciferase immunoprecipitation system assays in 100 cross-sectional or longitudinal samples from patients with SARS-CoV-2 infection. A subset of samples was tested both with and without heat inactivation. Results At >14 days after symptom onset, antibodies against SARS-CoV-2 nucleocapsid protein showed 100% sensitivity and 100% specificity, whereas antibodies to spike protein were detected with 91% sensitivity and 100% specificity. Neither antibody levels nor the rate of seropositivity were significantly reduced by heat inactivation of samples. Analysis of daily samples from 6 patients with COVID-19 showed anti-nucleocapsid and spike protein antibodies appearing between days 8 and 14 after initial symptoms. Immunocompromised patients generally had a delayed antibody response to SARS-CoV-2, compared with immunocompetent patients. Conclusions Antibody to the nucleocapsid protein of SARS-CoV-2 is more sensitive than spike protein antibody for detecting early infection. Analyzing heat-inactivated samples with a luciferase immunoprecipitation system assay is a safe and sensitive method for detecting SARS-CoV-2 antibodies.

No abstract

word count: 198 37 38for use under a CC0 license. ABSTRACT 39Background: SARS-CoV-2, the cause of coronavirus disease 2019 , is associated 40 with respiratory-related morbidity and mortality. Assays to detect virus-specific antibodies are 41 important to understand the prevalence of infection and the course of the immune response. 42 Methodology: Quantitative measurements of plasma or serum antibodies by luciferase 43 immunoprecipitation assay systems (LIPS) to the nucleocapsid and spike proteins were analyzed 44 in 100 cross-sectional or longitudinal samples from SARS-CoV-2-infected patients. A subset of 45 samples was tested with and without heat inactivation.46Results: Fifteen or more days after symptom onset, antibodies against SARS-CoV-2 47 nucleocapsid protein showed 100% sensitivity and 100% specificity, while antibodies to spike 48 protein were detected with 91% sensitivity and 100% specificity. Neither antibody levels nor the 49 rate of seropositivity were significantly reduced by heat inactivation of samples. Analysis of 50 daily samples from six patients with COVID-19 showed anti-nucleocapsid and spike antibodies 51 appearing between day 8 to day 14 after initial symptoms. Immunocompromised patients 52 generally had a delayed antibody response to SARS-CoV-2 compared to immunocompetent 53 patients. 54Conclusions: Antibody to the nucleocapsid protein of SARS-CoV-2 is more sensitive than 55 spike protein antibody for detecting early infection. Analyzing heat-inactivated samples by LIPS 56 is a safe and sensitive method for detecting SARS-CoV-2 antibodies. 57 58 feature of COVID-19 SARS-CoV-2 is virus-associated pneumonitis [5-7]. Unlike other highly 64 pathogenic coronaviruses such as SARS/SARS-CoV-1 and Middle East respiratory syndrome 65 coronavirus (MERS-CoV) [8], SARS-CoV-2 spreads more rapidly and reached six of the seven 66 continents, including North America [9], within three months of the initial outbreak. Nucleic 67 acid-based testing of oropharyngeal or nasopharyngeal swabs and saliva is useful for diagnosing 68 acute infection. SARS-CoV-2 virus RNA can often be detected in upper respiratory secretions at 69 the time of the first appearance of symptoms, peaks during the first week, and later declines with 70 time [10, 11]. RNA from SARS-CoV-2, like the related SARS-CoV-1 [12], can also be detected 71 in blood [11, 13], and high levels of circulating viral RNA are associated with more severe 72 disease [13]. 73 Assessment of the antibody response to SARS-CoV-2 should complement the RNA-74 based tests and improve our understanding of the disease course, contribute to epidemiological 75 studies and inform vaccine development. Antibodies to the nucleocapsid protein are the most 76 sensitive target for serologic diagnosis of infection with SARS-CoV-1 [14, 15]. Antibodies 77 against the spike protein of SARS-CoV-1, the target of neutralizing antibody and vaccine 78 development, emerge at a later time than those against the nucleocapsid protein. Recently, 79 several groups have reported serological dia...

No abstract