Decreased serum vitamin D level as a prognostic marker in patients with COVID-19 (preprint)

Background: The corona virus disease 2019 (COVID-19) pandemic, which is caused by severe acute respiratory syndrome coronavirus 2, is still localized outbreak and has resulted in a high rate of infection and severe disease in older patients with comorbidities. The vitamin D status of the population has been found to be an important factor that could influence outcome of COVID-19. However, whether vitamin D can lessen the symptoms or severity of COVID-19 still remains controversial. Methods: A total of 719 patients with confirmed COVID-19 were enrolled retrospectively in this study from April 13 to June 6, 2022 at Shanghai Forth People's Hospital. The circulating levels of 25(OH)D3, inflammatory factors, and clinical parameters were assayed. Time to viral RNA clearance (TVRC), classification and prognosis of COVID-19 were used to evaluate the severity of COVID-19 infection. Results: The median age was 76 years (interquartile range, IQR, 64.5-84.6), 44.1% of patients were male, and the TVRC was 11 days (IQR, 7-16) in this population. The median level of 25(OH)D3 was 27.15 (IQR, 19.31-38.89) nmol/L. Patients with lower serum 25(OH)D3 had prolonged time to viral clearance, more obvious inflammatory response, more severe respiratory symptoms and higher risks of impaired hepatic and renal function. Multiple regression analyses revealed that serum 25(OH)D3 level was negatively associated with TVRC independently. ROC curve showed the serum vitamin D level could predict the severity classification and prognosis of COVID-19 significantly.Conclusions: Serum 25(OH)D3 level is independently associated with the severity of COVID-19 in elderly, and it could be used as a predictor of the severity of COVID-19. In addition, supplementation with vitamin D might provide beneficial effects in old patients with COVID-19.

COVID-19 Detection Using CT Image Based On YOLOv5 Network (preprint)

Computer aided diagnosis (CAD) increases diagnosis efficiency, helping doctors providing a quick and confident diagnosis, it has played an important role in the treatment of COVID19. In our task, we solve the problem about abnormality detection and classification. The dataset provided by Kaggle platform and we choose YOLOv5 as our model. We introduce some methods on objective detection in the related work section, the objection detection can be divided into two streams: onestage and two stage. The representational model are Faster RCNN and YOLO series. Then we describe the YOLOv5 model in the detail. Compared Experiments and results are shown in section IV. We choose mean average precision (mAP) as our experiments' metrics, and the higher (mean) mAP is, the better result the model will gain. mAP@0.5 of our YOLOv5s is 0.623 which is 0.157 and 0.101 higher than Faster RCNN and EfficientDet respectively.