ABSTRACT
Background Effective isolation and early treatment of coronavirus disease 2019 (COVID-19) relies on rapid, accurate, and straightforward diagnostic tools. In response to the rapidly increasing number of cases, reverse transcription-quantitative polymerase chain reaction (RT-qPCR) assays for multiple target genes have become widely available in the market. Methods In total, 236 COVID-19 patients with positive results in both RT-qPCR and rapid antigen diagnosis (Ag-RDT) were enrolled in the study. The cycle threshold (Ct) was compared with different onset times and target genes. Comparison between groups was evaluated with the Kruskal-Wallis test and Dunn test. The correlation between target genes was analyzed by Spearman. Results In samples of Ct ≤ 21, Ct was different for the nucleocapsid (N), open reading frame 1ab (ORF1ab), and envelope (E) genes (P < 0.05). Mild COVID-19 patients within 7 days of onset accounted for 67.80% of all enrolled patients. At the above stage, all target genes reached the trough of Ct, and N genes showed lower values than the other target genes. The Ct of the ORF1ab and N gene in asymptomatic patients differed from those of mild patients within 7 days and more than 14 days of onset. The kits used in the study showed strong consistency among target genes, with all correlation coefficients >0.870. Conclusion RT-qPCR confirmed that the N gene performed well in Ct ≤ 21 and samples within 7 days of onset. Ag-RDT was discriminatory for patients within 7 days of onset. This study facilitated early identification and control of COVID-19 prevalence among patients.
ABSTRACT
The temporal change patterns of laboratory data may provide insightful clues into the whole course of COVID-19. This study aimed to evaluate longitudinal change patterns of key laboratory tests in patients with COVID-19, and identify independent prognostic factors by examining the associations between laboratory findings and outcomes of patients. This multicenter study included 56 patients with COVID-19 treated in Jilin Province, China, from January 21, 2020 to March 5, 2020. The laboratory findings, epidemiological characteristics and demographic data were extracted from electronic medical records. The average value of eosinophils and carbon dioxide combining power continued to significantly increase, while the average value of cardiac troponin I and mean platelet volume decreased throughout the course of the disease. The average value of lymphocytes approached the lower limit of the reference interval for the first 5 days and then rose slowly thereafter. The average value of thrombocytocrit peaked on day 7 and slowly declined thereafter. The average value of mean corpuscular volume and serum sodium showed an upward trend from day 8 and day 15, respectively. Age, sex, lactate dehydrogenase, platelet count and globulin level were included in the final model to predict the probability of recovery. The above parameters were verified in 24 patients with COVID-19 in another area of Jilin Province. The risk stratification and management of patients with COVID-19 could be improved according to the temporal trajectories of laboratory tests.
Subject(s)
COVID-19 Testing/methods , COVID-19/diagnosis , COVID-19/therapy , Adult , COVID-19/blood , COVID-19/epidemiology , Carbon Dioxide/blood , China/epidemiology , Female , Globulins/metabolism , Humans , Male , Middle Aged , Platelet Count , Prognosis , SARS-CoV-2/isolation & purification , Troponin I/bloodABSTRACT
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the pathogen that causes coronavirus disease 2019 (COVID-19), which was first detected in Wuhan, China. Recent studies have updated the epidemiologic and clinical characteristics of COVID-19 continuously. In China, diagnostic tests and laboratory tests of specimens from persons under investigation are usually performed in a biosafety level 2 environment. Laboratory staff may be at greater risk of exposure due to a higher concentration and invasiveness of emerging pathogens. Current infection prevention strategies are based on lessons learned from severe acute respiratory syndrome, expert judgments, and related regulations. This article summarizes biosafety prevention and control measures performed in severe acute respiratory syndrome coronavirus 2 testing activities and provides practical suggestions for laboratory staff to avoid laboratory-acquired infections in dealing with public health emergencies.