Study on the Age of SARS-CoV-2 in Respiratory and Digestive Tract Samples: A Retrospective Study guixian-wu1,dongqin-lv*,susu-He,qian-chen,lin-ling,shaungquan-yan,xiaomai-wu,yongpo-jiang

Abstract Background: An acute respiratory disease, caused by a novel coronavirus (SARS-CoV-2, previously known as 2019-nCoV), the coronavirus disease 2019 (COVID-19), has spread throughout China and received worldwide attention. After nearly 2 months efforts by the Chinese government and people from all walks of life, the epidemic in China has gradually been controlled. The awareness of the disease has gradually increased. We have detected the SARS-CoV-2 gene in the patient's sputum, throat swabs and feces, blood and even urine samples, but whether the SARS-CoV-2 RNA is detected in the upper and lower respiratory tracts and the extrapulmonary age is unknown.Methods: We collected data from 146 patients admitted to the Public Health Center of Taizhou Hospital, Zhejiang University, China from January 23, 2020 to March 11, 2020, and confirmed the diagnosis of new-type coronavirus pneumonia by RT-PCR. The final selection was made after screening. For a total of 134 confirmed patients, we collected their clinical data and sputum, nasopharyngeal swabs or throat swabs, fecal nucleic acid test results, and calculated the age of each specimen.Results: A total of 134 confirmed patients were included in the study; of them, 93 were of the common type, and 41 were critically ill. There were no significant differences between males and females, P = 0.853) and their epidemiological history (P = 0.441). The average age of severe patients was 55.85 ± 13.28 years, which was higher than that of common patients at 44.06 ± 12.86 years (P = 0.00). The results showed that the time of SARS-CoV-2 RNA in the upper respiratory tract was 15.1 ± 7.23 days for common patients and 20.56 ± 6.59 days for severe patients, which was longer than that of common patients (P = 0.00). The time of SARS-CoV-2 RNA in the lower respiratory tract was 27.45 ± 10.06 days for common patients and 29.78 ± 10.11 days for severe patients. There was no statistical difference (P = 0.328); SARS-CoV-2 RNA existed in the digestive tract. The time was 22.6 ± 7.69 days for common patients and 27.24 ± 7.86 days for severe patients, which was longer than that of common patients (P = 0.01). SARS-CoV-2 existed for a shorter time in the upper respiratory and digestive tracts than in the lower respiratory tract.CONCLUSION: SARS-CoV-2 is present in the lower respiratory tract for longer than the upper respiratory　and digestive tracts, and there were no statistical differences in the lower respiratory tract between common and severe patients.