Jul 21, 2021 · Friday 16th - Negative PCR Tuesday 20th - Positive PCR Wednesday 21st - Negative antigen test (lab tested Thursday 22nd - Negative PCR Monday 26th - Negative PCR. Daily rapid antigen tests (lateral flow) - all negative.

Jul 10, 2021 · "The specificity of antigen tests is generally as high as most NAATs, which means that false positive test results are unlikely when an antigen test is used according to the manufacturer’s instructions." So, maybe antigen isn't far behind, but it's not more specific. It's also good that PCR tests are more sensitive.

Jan 10, 2022 · That explains the scenario where someone was sick a couple of weeks ago and is now negative on the antigen test but positive on the PCR. The story is less clear with omicron because its possible that if omicron transmits at lower virus levels that there is a day or two at the beginning of infection where the antigen is still negative.

Oct 23, 2023 · Positive for pcr, negative for toxin but have symptoms I have all the symptoms of c diff, diarrhea, bloating , dizziness, and nausea. But the toxin test came back negative but the pcr test came back positive, my dr said to take antibiotics should I?

Sep 16, 2021 · That’s definitely a PCR test if it says dna in the title. But the current recommendation is to treat with a positive PCR if symptoms are present. If symptoms are not present I wouldn’t worry about retesting at all. PCR detects the presence of toxigenic c diff bacterial DNA/RNA.

Jul 15, 2021 · Flying Canada-US — PCR vs. Antigen Test I am going to be flying to the US from Canada soon and am a bit confused by the COVID testing requirements. It seems like a rapid, antigen test is enough to enter the US but Canada requires a PCR test for anyone returning.

Aug 25, 2021 · My parents are traveling to Switzerland (Geneva) in September for a wedding. Before entering the USA they need to get a Covid-19 test. They are both vaccinated. I see that at the pharmacies in Geneva it is possible to make a RDV for a PCR test or test rapide antigénique. I am wondering if the test rapide antigénique is valid to enter the US.

Apr 17, 2022 · Rapid NAAT vs Antigen Is there any issue with using a rapid NAAT test or an Antigen test? I can't find any antigen tests nearby and due to the holiday weekend, our PCR results from yesterday might not be here in time for our sailing tomorrow..

Jan 4, 2022 · Very basic/non realistic example: If your pretest probability is 5% based on disease prevalence, a negative antigen test can lower your probability to say, 3% (total guess, just to outline the idea), and a negative PCR can lower it something lower than that (like 2%) because of a higher sensitivity.

May 30, 2022 · Whereas, the antigen home kits detects the virus' antigen, which is initially detectable in first exposure. Therefore, it's recommended to do the antigen test for initial tests versus PCR. With two positive antigen results from two different kits, I …