Antigen test v antibody test
[QUOTE=RiceRocket99;2521868]My head started to hurt after thinking about what you wrote haha. I don't have a medical background, so I can't provide any feedback. Guess I'll have to do some research on this. I don't fly out till February (3 months stay is up). I got time.[/QUOTE]RiceRocket99 is correct in that the CDC order permits either a negative PCR or a negative antigen test to enter US on an airplane. Both of these tests, when negative, show that you are not currently infected with the virus. The antigen test is far preferable to PCR test because it is faster (some places in US you get the results in 15 minutes) and cheaper. Zeos1 appears to be confusing antigen tests with antibody tests. Antibody test is a blood test that looks for antibodies in your system that fought off the virus. Having a positive antibody test is good because it means that your virus infection / Covid case is behind you and so it is unlikely (though not impossible) that you will get re-infected. Said differently, a positive antibody test means that you have some level of natural immunity to the virus. The CDC order will not allow you to enter the US via airplane on the basis of a positive antibody test. Likewise, the order will not allow you to enter the US via airplane just on the basis that you have already been vaccinated.
Antibody vs. Antigenic tests
In the last posts, I noted "antigen" tests were confused with "antibody" tests, for example but not only by Zeos1 ([URL]http://www.internationalsexguide.nl/forum/showthread.php?583-Medellin-Reports&p=2521844&viewfull=1#post2521844[/URL]).
Antigen tests seek specific proteins from the surface of the virus called "antigen". PCR tests seek the DNA. Antigen tests are intended to find if the virus is present, as PCR tests, but are less reliable than PCR.
What Zeos1 and other posters meant to mention is the test for antibodies, but he used the word "antigen". I don't want to be pedantic, but the difference is substantial.
CDC- PCR Not needed prior to re-entry
[QUOTE=Zeos1;2521892]I did. The headline says it all. A PCR test, or proof of recovery. Proof of recovery is a positive antigen test. A negative antigen test is useless. It means you have never had Covid, says nothing about whether you have it at the time of test.
So what will work for everyone is a negative PCR test. Which means you don't currently have it. By all means get the other one if you know or think you have had Covid. But if it doesn't show that then you will need the PCR test for sure.[/QUOTE]Zeos,
The CDC website:
[URL]https://www.cdc.gov/coronavirus/2019-ncov/travelers/testing-international-air-travelers.html[/URL]
When you scroll down:
"What is a verifiable test result?
A verifiable test result must be in the form of written documentation (paper or electronic copy) of a laboratory test result. Testing must be performed using a viral test (NAAT or antigen), and negative results must be provided to the airline prior to boarding. The test result documentation must include information that identifies the person, a specimen collection date and the type of test. A negative test result must show test was done within the 3 days before the flight. A positive test result must show the test was done within the 3 months before the flight. ".
Somebody correct me if I'm wrong, but zeos saying "a negative antigen test is useless". Is incorrect.
The website clearly states you can show the "negative results of an antigen test" prior to boarding.
And I believe the antigen (rapid) test can be those fast tests that can show results in an hour, not the PCR that take a few days.
Ill be in MDE next month, looking for clarification. so far what I have concluded:
-negative PCR test 96 hours or less before entry to colombia
-Negative antigen (rapid) test 72 hours prior to entry into the United States