tetano
Editor, Senior Moderator
Open Forum Infect Dis
. 2020 Aug 26;7(10)
faa379.
doi: 10.1093/ofid/ofaa379. eCollection 2020 Oct.
The Yield and Consistency of the Detection of SARS-CoV-2 in Multiple Respiratory Specimens
Haixia Zhang[SUP] 1 [/SUP], Meiling Chen[SUP] 2 [/SUP], Yanhua Zhang[SUP] 1 3 [/SUP], Jing Wen[SUP] 1 3 [/SUP], Yajie Wang[SUP] 4 [/SUP], Liming Wang[SUP] 3 5 [/SUP], Jinjin Guo[SUP] 4 [/SUP], Chen Liu[SUP] 4 [/SUP], Daijing Li[SUP] 1 3 [/SUP], Ying Wang[SUP] 1 3 [/SUP], Jing Bai[SUP] 1 3 [/SUP], Guiju Gao[SUP] 3 [/SUP], Sa Wang[SUP] 3 [/SUP], Di Yang[SUP] 3 [/SUP], Fengting Yu[SUP] 3 5 [/SUP], Liting Yan[SUP] 3 5 [/SUP], Gang Wan[SUP] 2 [/SUP], Fujie Zhang[SUP] 3 5 [/SUP]
Affiliations
Abstract
Background: Few studies have compared the yield of reverse transcription polymerase chain reaction (RT-PCR) assays in nasopharyngeal swabs, oropharyngeal swabs, and sputum for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) detection.
Methods: We conducted an observational study in Beijing Ditan Hospital, China. Specimens including nasopharyngeal swabs, oropharyngeal swabs, and sputum from confirmed coronavirus 2019 patients were collected for RT-PCR testing. Disease duration was calculated from the date of symptom onset to the date of specimen collection and divided into 3 groups: ≤14 days, 14-21 days, and >21 days. We compared positive rates across the 3 specimens collected. The kappa coefficient was used to evaluate the consistency of RT-PCR results between different specimens.
Results: A total of 291 specimens were collected and tested from 43 confirmed patients. Among specimens collected with a disease duration of ≤14 days, the positive rate was highest in sputum (79.2%); this rate was significantly higher than that in nasopharyngeal swabs (37.5%; P = .003) and oropharyngeal swabs (20.8%; P < .001). Similar findings were observed with the disease durations of 14-21 days and >21 days. The consistency of testing results between nasopharyngeal swabs and oropharyngeal swabs was low with the disease durations of ≤14 days and >21 days. The consistency between the sputum and oropharyngeal swabs and between the sputum and nasopharyngeal swabs was very low across all 3 disease durations, with statistical significance.
Conclusions: Compared with nasopharyngeal swabs and oropharyngeal swabs, sputum had the highest yield of SARS-CoV-2 detection. Nasopharyngeal swabs and oropharyngeal swabs had a similar yield. If sputum is not feasible, a nasopharyngeal swab can be recommended for the detection of SARS-CoV-2, and early testing is needed.
Keywords: SARS-CoV-2; nasopharyngeal swabs; oropharyngeal swabs; positive rate; sputum.
. 2020 Aug 26;7(10)
faa379.doi: 10.1093/ofid/ofaa379. eCollection 2020 Oct.
The Yield and Consistency of the Detection of SARS-CoV-2 in Multiple Respiratory Specimens
Haixia Zhang[SUP] 1 [/SUP], Meiling Chen[SUP] 2 [/SUP], Yanhua Zhang[SUP] 1 3 [/SUP], Jing Wen[SUP] 1 3 [/SUP], Yajie Wang[SUP] 4 [/SUP], Liming Wang[SUP] 3 5 [/SUP], Jinjin Guo[SUP] 4 [/SUP], Chen Liu[SUP] 4 [/SUP], Daijing Li[SUP] 1 3 [/SUP], Ying Wang[SUP] 1 3 [/SUP], Jing Bai[SUP] 1 3 [/SUP], Guiju Gao[SUP] 3 [/SUP], Sa Wang[SUP] 3 [/SUP], Di Yang[SUP] 3 [/SUP], Fengting Yu[SUP] 3 5 [/SUP], Liting Yan[SUP] 3 5 [/SUP], Gang Wan[SUP] 2 [/SUP], Fujie Zhang[SUP] 3 5 [/SUP]
Affiliations
- PMID: 33072810
- PMCID: PMC7499703
- DOI: 10.1093/ofid/ofaa379
Abstract
Background: Few studies have compared the yield of reverse transcription polymerase chain reaction (RT-PCR) assays in nasopharyngeal swabs, oropharyngeal swabs, and sputum for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) detection.
Methods: We conducted an observational study in Beijing Ditan Hospital, China. Specimens including nasopharyngeal swabs, oropharyngeal swabs, and sputum from confirmed coronavirus 2019 patients were collected for RT-PCR testing. Disease duration was calculated from the date of symptom onset to the date of specimen collection and divided into 3 groups: ≤14 days, 14-21 days, and >21 days. We compared positive rates across the 3 specimens collected. The kappa coefficient was used to evaluate the consistency of RT-PCR results between different specimens.
Results: A total of 291 specimens were collected and tested from 43 confirmed patients. Among specimens collected with a disease duration of ≤14 days, the positive rate was highest in sputum (79.2%); this rate was significantly higher than that in nasopharyngeal swabs (37.5%; P = .003) and oropharyngeal swabs (20.8%; P < .001). Similar findings were observed with the disease durations of 14-21 days and >21 days. The consistency of testing results between nasopharyngeal swabs and oropharyngeal swabs was low with the disease durations of ≤14 days and >21 days. The consistency between the sputum and oropharyngeal swabs and between the sputum and nasopharyngeal swabs was very low across all 3 disease durations, with statistical significance.
Conclusions: Compared with nasopharyngeal swabs and oropharyngeal swabs, sputum had the highest yield of SARS-CoV-2 detection. Nasopharyngeal swabs and oropharyngeal swabs had a similar yield. If sputum is not feasible, a nasopharyngeal swab can be recommended for the detection of SARS-CoV-2, and early testing is needed.
Keywords: SARS-CoV-2; nasopharyngeal swabs; oropharyngeal swabs; positive rate; sputum.