Why did countries initially presume that detecting COVID-19 requires a deep nasal swab?
According to a recent paper:
To validate the use of saliva for SARS-CoV-2
detection, we tested nasopharyngeal and saliva samples from confirmed
COVID-19 patients and self-collected samples from healthcare workers
on COVID-19 wards. When we compared SARS-CoV-2
detection from patient-matched nasopharyngeal and saliva
samples, we found that saliva yielded greater detection sensitivity
and consistency throughout the
course of infection. Furthermore, we report less variability in
self-sample collection of saliva. Taken together, our findings
demonstrate that saliva is a viable and more
sensitive alternative to nasopharyngeal swabs and could enable at-home
self-administered sample collection for accurate large-scale
SARS-CoV-2 testing.
This made me wonder... why did countries initially presume that deep nasal swabs are the default route for detecting the virus? Why didn't we start out with basic saliva samples and then try out invasive sampling, rather than the other way around?
(1)1 Comments
Sorted by latest first Latest Oldest Best
From the paper you linked to
nasopharyngeal swabs are commonly used in respiratory virus diagnostics
So clearly it was preferred for Covid-19 because of the "received wisdom" from other respiratory virus illnesses. (To pick a random example, the 2005 WHO guidlines for avian influenza don't mention saliva samples, but various kinds of swabs and washes (for the upper respiratory tract): nasal swab,
nasopharyngeal swab, nasopharyngeal aspirate, nasal wash, throat swab.)
If you want to ask why saliva sampling is not a method more widely used (instead of, or, in addition to nasopharyngeal swabs) in other respiratory virus diagnostics, modify your question according (incl. tag).
Terms of Use Privacy policy Contact About Cancellation policy © freshhoot.com2025 All Rights reserved.