Quantitative Detection and Viral Load Analysis of SARS-CoV-2 in Infected Patients.
Clin Infect Dis
; 71(15): 793-798, 2020 07 28.
Article
em En
| MEDLINE
| ID: mdl-32221523
ABSTRACT
BACKGROUND:
Coronavirus disease 2019 (COVID-19) has become a public health emergency. The widely used reverse transcription-polymerase chain reaction (RT-PCR) method has limitations for clinical diagnosis and treatment.METHODS:
A total of 323 samples from 76 COVID-19-confirmed patients were analyzed by droplet digital PCR (ddPCR) and RT-PCR based 2 target genes (ORF1ab and N). Nasal swabs, throat swabs, sputum, blood, and urine were collected. Clinical and imaging data were obtained for clinical staging.RESULTS:
In 95 samples that tested positive by both methods, the cycle threshold (Ct) of RT-PCR was highly correlated with the copy number of ddPCR (ORF1ab gene, R2â =â 0.83; N gene, R2â =â 0.87). Four (4/161) negative and 41 (41/67) single-gene positive samples tested by RT-PCR were positive according to ddPCR with viral loads ranging from 11.1 to 123.2 copies/test. The viral load of respiratory samples was then compared and the average viral load in sputum (17â 429â ±â 6920 copies/test) was found to be significantly higher than in throat swabs (2552â ±â 1965 copies/test, Pâ <â .001) and nasal swabs (651â ±â 501 copies/test, Pâ <â .001). Furthermore, the viral loads in the early and progressive stages were significantly higher than that in the recovery stage (46â 800â ±â 17â 272 vs 1252â ±â 1027, Pâ <â .001) analyzed by sputum samples.CONCLUSIONS:
Quantitative monitoring of viral load in lower respiratory tract samples helps to evaluate disease progression, especially in cases of low viral load.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Pneumonia Viral
/
Infecções por Coronavirus
/
Betacoronavirus
Tipo de estudo:
Diagnostic_studies
Limite:
Adult
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Female
/
Humans
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Male
/
Middle aged
Idioma:
En
Revista:
Clin Infect Dis
Ano de publicação:
2020
Tipo de documento:
Article