Belgium – Covid-19 coronavirus: using saliva samples to detect SARS-CoV-2 as an alternative to sampling via a deep nasal swab?
24 September 2020
The Belgian federal taskforce on testing and shortages commissioned a study that was launched on 28 May 2020 on the use of saliva samples as an alternative to sampling via a deep nasal swab (nasopharyngeal) to detect SARS-CoV-2 using PCR molecular detection tests.
The purpose of the study, supported by Sciensano, a public research institution, and the Federal Agency for Medicines and Health Products (FAMPH), was to detect how sensitive SARS-CoV-2 detection is in saliva samples (via a saliva swab and with a simple saliva receptacle) in different populations and during the infection cycle when compared to sampling through the nose. The collecting of saliva samples has several advantages in comparison to classic sampling via a nasal swab: it is much easier, less intrusive and unpleasant for the patient and it is minimises risk for healthcare professionals since patients can collect their own samples.
According to a press release published by the FAMPH on 6 August 2020, the study found that subjects with a low viral RNA load were detected via a conventional nasopharyngeal swab, but not with saliva. In contrast, the results for subjects with medium to high viral RNA loads were satisfactory. As a result, the study concludes as following: saliva samples are less sensitive than nasopharyngeal samples to detect the presence of the SARS-CoV-2 RNA, however, saliva sampling might have value to identify asymptomatic individuals with medium to high viral load in the context of systematic screening campaigns.
The following partners of the national testing platform participated in the study:
- The national reference center for respiratory pathogens.
- The Belgian military.
A prior version of this post was originally published by the same authors in Practical Law – Life Sciences, October 2020 Issue (Thomson Reuters).