evidence: Nasal swabs are preferred over mouth swabs as a more accurate way of testing for COVID-19. [...] We rated as Pants on Fire a claim that "the spot where they are ‘getting a sample’ for the COVID-19 test is called your Blood-Brain Barrier." The swabs do not go anywhere near the blood-brain barrier, the name given to the unique protective properties found in blood vessels that supply blood to the central nervous system. And there is no evidence that getting a COVID-19 test could cause anything more serious than temporary irritation. [...] USA Today, "Fact check: Though nasal test for COVID-19 swabs deep into the nose, nothing is implanted," July 11, 2020