Viral and host factors related to the clinic outcome of the SARS-CoV-2 infection (preprint)

At least three months have been passed since the outbreak of the severe acute respiratory disease, COVID-19 in Wuhan city, China in December 2019, caused by the infection of a novel coronavirus, SARS-CoV-2. 1,2 . Due to its rapid spread throughout China and abroad, knowledge sharing for both its epidemiology and clinic manifestations is urgently need. Here we analyzed the clinical, molecular and immunological data from 326 confirmed cases of SARS-CoV-2 infection in Shanghai. Genomic sequences assembled from 112 quality samples together with uploaded sequences in Global Initiative on Sharing All Influenza Data (GISAID) showed a stable evolution and suggested two major lineages with differential exposure history during the earliest outbreak in Wuhan. Nevertheless, they exhibited similar virulence and clinical outcomes. Lymphocytopenia, especially the reduced CD4+ and CD8+ T cell counts upon admission, was predictive of disease progression. High level of IL-6 and IL-8 during treatment was observed in severe and critical patients and correlated with decreased lymphocyte count. The determinants of disease severity seemed to stem mostly from host factors such age, lymphocytopenia and its associated cytokine storm whereas viral genetic variation did not significantly affect the outcomes. This comprehensive analysis on the molecular, immunological and clinical data provides a panorama of the key determinants related to the disease outcomes which should be helpful for improving the current combat against this extremely aggressive pandemic.Authors Xiaonan Zhang, Yun Tan, Yun Ling, Gang Lu, Feng Liu, and Zhigang Yi contributed equally to this work.

The feasibility of convalescent plasma therapy in severe COVID-19 patients: a pilot study (preprint)

Currently, there are no approved specific antiviral agents for 2019 novel coronavirus disease (COVID-19). In this study, ten severe patients confirmed by real-time viral RNA test were enrolled prospectively. One dose of 200 mL convalescent plasma (CP) derived from recently recovered donors with the neutralizing antibody titers above 1:640 was transfused to the patients as an addition to maximal supportive care and antiviral agents. The primary endpoint was the safety of CP transfusion. The second endpoints were the improvement of clinical symptoms and laboratory parameters within 3 days after CP transfusion. The median time from onset of illness to CP transfusion was 16.5 days. After CP transfusion, the level of neutralizing antibody increased rapidly up to 1:640 in five cases, while that of the other four cases maintained at a high level (1:640). The clinical symptoms were significantly improved along with increase of oxyhemoglobin saturation within 3 days. Several parameters tended to improve as compared to pre-transfusion, including increased lymphocyte counts (0.65*109/L vs. 0.76*109/L) and decreased C-reactive protein (55.98 mg/L vs. 18.13 mg/L). Radiological examinations showed varying degrees of absorption of lung lesionswithin 7 days. The viral load was undetectable after transfusion in seven patients who had previous viremia. No severe adverse effects were observed. This study showed CP therapy was welltolerated and could potentially improve the clinical outcomes through neutralizing viremia in severe COVID-19 cases. The optimal dose and time point, as well as the clinical benefit of CP therapy, needs further investigation in larger well-controlled trials.