The nasal and pharyngeal swab techniques during the COVID-19-pandemic - the ENT-perspective - SARS-CoV-2, Coronavirus, nasal swab, pharyngeal swab, complications

Abstract

Since the beginning of the SARS-CoV-2 pandemic, swabs or other samples have increasingly been taken from the upper aero-digestive tract, since high viral loads exist here, especially in the early stages of the disease. As diagnostic options, swabs from the anterior nose, from the nasopharynx, from the oropharynx or the extraction of throat rinse water or saliva are possible. The laboratory methods available are antigen tests that can be read in a few minutes or more lengthy RT-PCR methods in a lab. Swabs are carried out by physicians, medical staff, laypeople and in the self-test, in each case according to prior instructions. Many of these factors therefore have an influence on the informative value and the sensitivity of the entire diagnostic process. The PCR laboratory method is more sensitive than the antigen method; the swabs from the nasopharynx are considered the most valid smear site; correct execution of a test can be achieved even with non-professional individuals with good instructions. Complications with such swabs are reported very rarely, given the assumed number of procedures performed. Short-term nosebleeds after traumatic smears can be assumed without publications about it being found. Broken parts of swabs had to be removed by an ENT doctor. There are only very few reports on injuries to the skullbase with CSF-leaks, including 2 times with anomalies such as meningoceles. The choice of a suitable diagnostic medium depends on many parameters such as availability, the timing of the result, a smear test by knowledgeable staff or a self-test, and a number of other practical considerations.