Association of early virus nucleic acid in throat swabs and clinical characteristics in COVID-19 patients early in their illness

Abstract:

Objective：To investigate the relationship between early laboratory indexes and clinical manifestations and radiographic characteristics in coronavirus disease 2019（COVID-19）. Methods：In this retrospective study，30 confirmed cases of COVID-19 in Second Xiangya Hospital（Changsha） from January 24th to February 9th，2020 were enrolled，viral loads in throat swabs of the patients and their correlation with clinical manifestations and imaging characteristics were analyzed. Results：On admission，4 out of 30 COVID-19 patients（13.33%） had no clinical symptoms，23 patients（76.67%） had fever. Imaging findings were observed in 20 patients（66.67%），while no obvious abnormalities were observed in 10 patients（33.33%）. Ct value of viral nucleic acid in throat swabs of asymptomatic COVID-19 patientswas basically the same as in those patients with clinical symptoms. Compared with patients with no abnormality in imaging，patients with imaging manifestation of pneumonia had significantly increased Ct value（P=0.001） of viral nucleic acid and body temperature（P=0.014）. After adjusted for gender and age by logistic regression model，Ct value of viral nucleic acid in throat swabs was positively correlated with the imaging characteristics of pneumonia（OR=1.34，95%CI=1.07-1.66，P=0.009）. Conclusion：Asymptomatic COVID-19 patients had a similar level of viral load of throat swabs as symptomatic COVID-19 patients at an early stage. The viral load of throat swabs was negatively correlated with pulmonary imaging characteristics at an early stage of COVID-19 patients.