Thread: pandemic
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Old 03-16-2021, 12:31 PM   #33
Lakegeezer
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Quote:
Originally Posted by baygo View Post
Thanks for the link Baygo. I'm still trying to interpret what was written by the WHO. The relevant paragraph is:

WHO guidance Diagnostic testing for SARS-CoV-2 states that careful interpretation of weak positive results is needed (1). The cycle threshold (Ct) needed to detect virus is inversely proportional to the patient’s viral load. Where test results do not correspond with the clinical presentation, a new specimen should be taken and retested using the same or different NAT technology.

WHO reminds IVD users that disease prevalence alters the predictive value of test results; as disease prevalence decreases, the risk of false positive increases (2). This means that the probability that a person who has a positive result (SARS-CoV-2 detected) is truly infected with SARS-CoV-2 decreases as prevalence decreases, irrespective of the claimed specificity.


The WHO article is poorly written, but I don't come to the same conclusion that there is no asymptomatic condition. Nowhere does it say what viral load is required before symptoms show or for a person to be infectious. It also doesn't report how many labs weren't following the protocols so we don't know how many positive test results were false.

It was written for the labs that do the testing, clarifying information on why not following the testing protocols might lead to reporting false positives. That topic was covered in a NPR article.

It is likely that some people quarantined due to a positive test when they didn't have to just as it is likely some people had the virus, were never tested and so should have been quarantined.

I'm still trying to understand why the Lakes Region infection rate was so low during the summer, when tourists flocked in, and so much higher since the fall. The state daily infection rate, while rising again, has fallen to where it was in November and the deaths/day have fallen over 90% over the peak.

With vaccinations rolling out, those that were careful can start to mingle with those that were never careful and open things up again.
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