[url=http://beobuild.rs/forum/viewtopic.php?p=775334#p775334:2mu1ylg3 je napisao(la):
MC_ » 16 Sep 2020 08:37 am[/url]":2mu1ylg3]Kad smo kod testova.
krajem februara imao sam sve simptome kovida. Juce sam obavio "brzi" test na antitela. Ispao sam negativan.
Da li je to realno i da li je brzi test pouzdan?
Ni jedan test nije potpuno pouzdan, a to još zavisi ne samo od samog testa nego i od toga kako je kod PCR testa uzet uzorak, da li se virus uopšte nalazi na tom mestu ili negde drugde u organizmu, a kod antigenskih od karakteristika imunog sistema, u kojoj je tačno meri čovek ranije bio izložen virusu i koliko je to davno bilo. Kad je u pitanju otkrivanje tekuće, a ne prošle zaraženosti, pouzdaniji je PCR test od antigenskog.
U tvom slučaju, verovatnoća pogrešnog rezultata je MOŽDA 20%, mada je test 7 meseci posle potencijalnog zaražavanja veoma dug period za trenutno znanje koliko traju antitela. Verovatno treba poći od toga da zaista nemaš antitela.
Diagnostic tests for current infection
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Molecular tests (also called PCR tests, viral RNA tests, nucleic acid tests)
What about accuracy? False negatives — that is, a test that says you don’t have the virus when you actually do have the virus — may occur. The reported rate of
false negatives is as low as 2% and as high as 37%. The reported rate of
false positives — that is, a test that says you have the virus when you actually do not —
is 5% or lower. A molecular test using a deep nasal swab is usually the best option, because it will have fewer false negative results than other diagnostic tests or samples from throat swabs or saliva. People who are in the hospital, though, may have other types of samples taken.
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Antigen tests
What about accuracy? The reported rate of
false negative results is as high as 50%, which is why antigen tests are not favored by the FDA as a single test for active infection. However, because antigen testing is quicker, less expensive, and requires less complex technology to perform than molecular testing, some experts recommend repeated antigen testing as a reasonable strategy. According to one test manufacturer, the
false positive rate of antigen testing is near zero. So, the recent experience of Ohio Governor Mike DeWine, who apparently had a false-positive result from an antigen test, is rare.
Tests for past infection
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Antibody tests (also called serologic testing)
What about accuracy? Having an antibody test too early can lead to false negative results. That’s because it takes a week or two after infection for your immune system to produce antibodies. The reported rate of
false negatives is 20%. However, the range of
false negatives is from 0% to 30% depending on the study and when in the course of infection the test is performed.
Research suggests antibody levels may wane over just a few months. And while a positive antibody test proves you’ve been exposed to the virus, it’s not yet known whether such results indicate a lack of contagiousness or long-lasting, protective immunity.
The true accuracy of tests for COVID-19 is uncertain
Unfortunately, it’s not clear exactly how accurate any of these tests are. There are several reasons for this:
https://www.health.harvard.edu/blog/whi ... 0081020734