It’s a long standing problem with these kind of rapid diagnostics for respiratory illnesses: https://www.cbsnews.com/news/rapid-flu-tests-only-50-to-70-percent

It’s a long standing problem with these kind of rapid diagnostics for respiratory illnesses: https://www.cbsnews.com/news/rapid-flu-tests-only-50-to-70-percent-accurate-cdc-says/ https://www.cbsnews.com/news/rapid-flu-tests-only-50-to-70-p... Doing two swabs helps mitigate this, as does comparing anal and oral swabs. Here’s a more thorough breakdown: https://www.tandfonline.com/doi/full/10.1080/22221751.2020.1729071 https://www.tandfonline.com/doi/full/10.1080/22221751.2020.1...