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Background2019-Novel coronavirus (2019-nCoV) outbreaks create challenges for hospital laboratories because thousands of samples must be evaluated each day. Sample types, interpretation methods, and corresponding laboratory standards must be established. The possibility of other infections should be assessed to provide a basis for clinical classification, isolation, and treatment. Accordingly, in the present study, we evaluated the testing methods for 2019-nCoV and co-infections. MethodsWe used a fluorescence-based quantitative PCR kit urgently distributed by the Chinese CDC to detect 8274 close contacts in the Wuhan region against two loci on the 2019-nCoV genome. We also analyzed 613 patients with fever who underwent multiple tests for 13 respiratory pathogens; 316 subjects were also tested for 2019-nCoV. FindingsAmong the 8274 subjects, 2745 (33.2%) had 2019-nCoV infection; 5277 (63.8%) subjects showed negative results in the 2019-nCoV nucleic acid test (non-2019-nCoV); and 252 cases (3.0%) because only one target was positive, the diagnosis was not definitive. Eleven patients who originally had only one positive target were re-examined a few days later; 9 patients (81.8%) were finally defined as 2019-nCoV-positive, and 2 (18.2%) were finally defined as negative. The positive rates of nCoV-NP and nCovORF1ab were 34.7% and 34.7%, respectively. nCoV-NP-positive only and nCovORF1ab-positive cases accounted for 1.5% and 1.5%, respectively. In the 316 patients with multiple respiratory pathogens, 104 were positive for 2019-nCov and 6/104 had co-infection with coronavirus (3/104), influenza A virus (2/104), rhinovirus (2/104), and influenza A H3N2 (1/104); the remaining 212 patients had influenza A virus (11/202), influenza A H3N2 (11/202), rhinovirus (10/202), respiratory syncytial virus (7/202), influenza B virus (6/202), metapneumovirus (4/202), and coronavirus (2/202). InterpretationClinical testing methods for 2019-nCoV require improvement. Importantly, 5.8% of 2019-nCoV infected and 18.4% of non-2019-nCoV-infected patients had other pathogen infections. It is important to treat combined infections and perform rapid screening to avoid cross-contamination of patients. A test that quickly and simultaneously screens as many pathogens as possible is needed. FundingNo founding was received Research in contextO_ST_ABSEvidence before this studyC_ST_ABSWe searched PubMed for articles published up to January 31, 2020 using the keywords "2019 novel coronavirus" or "2019-nCoV". No published study on the characteristics of 2019-nCoV tests or 2019-nCoV co-infections was found. We only noted recent laboratory findings for other tests of patients infected with 2019-nCoV. Added value of this studyPositive detection of nCoV-NP or nCovORF1ab is presented, and individuals with/without 2019-nCoV infections or with inconclusive results were identified. Patients with inconclusive results may be diagnosed with 2019-nCoV infection or found to be negative for the infection after resampling and retesting in the next few days. Approximately 5.8% of the subjects diagnosed with 2019-nCoV had co-infection. Implications of all the available evidenceManagement of the population showing inconclusive results should be given attention; additionally, such results can be minimized by improving the sampling, sample pretreatment, and testing methodologies. When diagnosing 2019-nCoV subjects, the possibility of co-infection should be considered. Finally, better clinical detection methods are needed to simultaneously screen as many pathogens as possible.
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Objective@#To investigate the positive rate for 2019-nCoV tests and co-infections in Wuhan district.@*Methods@#A total of 8 274 cases in Wuhan were enrolled in this cross-sectional study during January 20 to February 9, 2020, and were tested for 2019-nCoV using fluorescence quantitative PCR. Both respiratory tract samples (nasopharynx, oropharynx, sputum and alveolar lavage fluid) and non-respiratory tract samples (urine, feces, anal swabs, blood and conjunctival sac swabs) were collected. If both orf1ab and N genes are positive, they are classified as nucleic acid test positive group; if both orf1ab and N genes are negative, they are classified as negative group; if single gene target is positive, they are classified as suspicious group. Individuals were divided into male group and female group according to sex. At the same time, 316 patients were tested for 13 respiratory pathogens by multiplex PCR.@*Results@#Among the 8 274 subjects, 2 745 (33.2%) were 2019-nCoV infected; 5 277 (63.8%) subjects showed negative results in the 2019-nCoV nucleic acid test; and 252 cases (3.05%) was not definitive (inconclusive result). The age of cases with COVID-19 patients and inconclusive cases was significantly higher than that of cases without 2019-nCoV infection (40 vs 56, t=27.569, P<0.001; 52 vs 56, t=6.774, P<0.001). The positive rate of 13 respiratory pathogens multiple tests was significantly lower in 104 subjects who were positive for 2019-nCoV compared with those in subjects who were negative for 2019-nCoV test (5.77% vs 18.39%, χ2=24.105, P=0.003). Four types of respiratory tract samples and five types of non-respiratory tract samples were found to be positive for 2019-nCoV nucleic acid test.@*Conclusion@#The 2019-nCoV nucleic acid positive rate in male is higher than in female. Co-infections should be pay close attention in COVID-19 patients. 2019-nCoV nucleic acid can be detected in non-respiratory tract samples.
ABSTRACT
Objective:To investigate the positive rate for 2019-nCoV tests and co-infections in Wuhan district.Methods:A total of 8 274 cases in Wuhan were enrolled in this cross-sectional study during January 20 to February 9 in 2020, and were tested for 2019-nCoV using fluorescence quantitative PCR. Both respiratory tract samples (nasopharynx, oropharynx, sputum and alveolar lavage fluid) and non-respiratory tract samples (urine, feces, anal swabs, blood and conjunctival sac swabs) were collected. If both orf1ab and N genes are positive, they are classified as nucleic acid test positive group; if both orf1ab and N genes are negative, they are classified as negative group; if single gene target is positive, they are classified as suspicious group. Individuals were divided into male group and female group according to sex. At the same time, 316 patients were tested for 13 respiratory pathogens by multiplex PCR.Results:Among the 8 274 subjects, 2 745 (33.17%) were 2019-nCoV infected; 5 277 (63.77%) subjects showed negative results in the 2019-nCoV nucleic acid test; and 252 cases (3.05%) was not definitive (inconclusive result). The age of cases with COVID-19 patients and inconclusive cases was significantly higher than that of cases without 2019-nCoV infection (56>40, t=27.569, P<0.001; 52>40, t=6.774, P<0.001). The positive rate of 13 respiratory pathogens multiple tests was significantly lower in 104 subjects who were positive for 2019-nCoV compared with those in subjects who were negative for 2019-nCoV test (5.77% vs 18.39%, χ 2=24.105, P=0.003). Four types of respiratory tract samples and five types of non-respiratory tract sampleswere found to be positive for 2019-nCoV nucleic acid test. Conclusion:The 2019-nCoV nucleic acid positive rate inmale is higher than infemale. Co-infections should be pay close attention in COVID-19 patients. 2019-nCoV nucleic acid can be detected in non-respiratory tract samples.
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Objective To investigate the effect of nucleocapsid (N) protein of severe acute respiratory syndrome-associated coronavirus (SARS-CoV) on the expression of cyclooxygenase-2 (COX-2). Methods 293T cells were co-transfected with reporter plasmid pCOX-2-Luc containing the luciferase gene under the control of COX-2 promoter and plasmids carrying individual genes of SARS-CoV, and luciferase activity was measured. Expression of COX-2 mRNA and protein was measured by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot. Results N protein of SARS-CoV enhanced COX-2 gene promoter activity, and upregulated COX-2 mRNA expression.COX-2 protein production in 293T cells was N protein concentration-dependent. Conclusion N protein of SARS-CoV could specifically activate COX-2 expression.
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Objective To explore the association between L-selectin gene P213S polymorphism and angina pectoris.Methods L-selectin gene P213S polymorphism in 138 patients with angina pectoris and 156 controls was detected by polymerase chain reaction restriction fragment length polymorphism(PCR-RFLP).The relationship between gene polymorphism of L-selectin and levels of serum lipids were also studied.Results L-selectin genotype frequencies of PP,PS,SS were 60.1%,36.3%,3.6% and 44.9%,48.1%,7.0% in angina pectoris group and control group respectively.Allele frequencies of P,S were 78.3%,21.7% and 68.9%,31.1% in angina pectoris group and control group respectively.There was significant differences of frequencies of genotype and allele of L-selectin P213S polymorphism between angina pectoris group and control group(P
