Medical Faculty, Institute of Medical Microbiology and Hospital Hygiene, Otto-von-Guericke-University Magdeburg, Leipziger Str. 44, 39120, Magdeburg, Germany.
Institute of Transfusion Medicine and Immunohematology, Otto-von-Guericke University Hospital, Leipziger Strasse 44, 39120, Magdeburg, Germany.
Infection. 2021 Jun;49(3):527-531. doi: 10.1007/s15010-021-01600-1. Epub 2021 Mar 18.
The optimal diagnostic specimen to detect SARS-CoV-2 by PCR in the upper respiratory tract is unclear. Mouthwash fluid has been reported as an alternative to nasopharyngeal and oropharyngeal swabs. We compared mouthwash fluid with a combined oro-nasopharyngeal swab regarding test performance.
In a large refugee facility, we retested individuals with a previous positive test for SARS-CoV-2 and their quarantined close contacts. All individuals were asymptomatic at the time of testing. First, a mouthwash (gargling for at least 5 s) with sterile water was performed. Then, with a single flocked swab the back of the throat and subsequently the nasopharynx were sampled. Samples were inactivated and analysed on a Roche cobas 6800 system with the Roche SARS-CoV-2 test.
Of 76 individuals, 39 (51%) tested positive for SARS-CoV-2 by oro-nasopharyngeal swab. Mouthwash detected 13 of 76 (17%) infections, but did not detect any additional infection. Samples that were positive in both tests, had lower cycle threshold (Ct)-values for oro-nasopharyngeal samples, indicating a higher virus concentration, compared to samples only positive in oro-nasopharyngeal swabs.
Mouthwash is not as sensitive as combined oro-nasopharyngeal swab in detecting upper respiratory tract infection.
通过 PCR 在上呼吸道检测 SARS-CoV-2 时，最佳的诊断标本尚不清楚。漱口水已被报道可替代鼻咽和口咽拭子。我们比较了漱口水与组合式口鼻咽拭子在检测性能方面的差异。
在一个大型难民营设施中，我们对先前 SARS-CoV-2 检测呈阳性的个体及其被隔离的密切接触者进行了复测。所有个体在检测时均无症状。首先，用无菌水进行漱口（至少漱口 5 秒）。然后，用单个植绒拭子对咽喉后部和随后的鼻咽部进行采样。采集的样本经灭活处理后，在罗氏 cobas 6800 系统上使用罗氏 SARS-CoV-2 检测进行分析。
在 76 名个体中，39 名（51%）通过鼻咽拭子检测出 SARS-CoV-2 呈阳性。漱口水检测出 76 名个体中的 13 名（17%）感染，但未检测到任何额外的感染。在两种检测均呈阳性的样本中，与仅在鼻咽拭子中呈阳性的样本相比，鼻咽样本的循环阈值（Ct）值更低，表明病毒浓度更高。
与组合式口鼻咽拭子相比，漱口水在检测上呼吸道感染时的敏感性较低。
