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Mystery in Wuhan: recovered coronavirus patients test negative then positive

npr.org

41–50 of 123 posts

Re: Mystery in Wuhan: recovered coronavirus patients test negative then positive

#41

Don't believe anything that comes out of China

this kind of lazy thinking is probably no small contributor to the rest of the wider world squandering its 2 month advantage over this virus.

I don't disagree with you that there are many suspicious acts surrounding China and this pandemic, but a blanket statement like that is nevertheless unconstructive.

Re: Mystery in Wuhan: recovered coronavirus patients test negative then positive

#43
post #28
post #12

Earlier quoted context omitted.

And if you swabbed an infected part of the body in the first place! In 205 patients with proven COVID-19 [...] bronchoalveolar lavage fluid was positive in 14/15 (93%), sputum 75/104 (72%), nasal swabs 5/8 (63%), brush biopsy 6/13 (46%), pharyngeal swabs 126/398 (32%), feces 44/153 (29%), blood 3/307 (1%), and urine 0/72 (0%). https://www.jwatch.org/na51116/2020/03/17/pharyngeal-and-nas...

Hol' up. > blood 3/307 (1%) Why isn't their blood rotten with virus?

If you're looking for a chemical explaination, I don't know, but the virus can work it's way around quite fine using the lymphatic system, so there's no "fitness" reason that would make it need to hang out in the blood.

Re: Mystery in Wuhan: recovered coronavirus patients test negative then positive

#44

Literally false positive and false negatives. In other words, if you test millions of people, there will be more people tested positive who DON'T have the disease vs. those who test positive and HAVE the disease.

Exactly! For any medical tests, there are 2 measurements: sensitivity and specificity, one to judge false positive and another judge the false negatives.

https://en.wikipedia.org/wiki/Sensitivity_and_specificity

Re: Mystery in Wuhan: recovered coronavirus patients test negative then positive

#45
post #8

Couple of thoughts: - I think we need to know a LOT more about the sensitivity, specificity, and accuracy of every test that's being deployed right now. I am 100% willing to believe that "testing negative and then positive" means "you have a pretty low viral load and our tests suck more than we're willing to admit out loud right now". - I think we need to be very clear that there are two kinds of tests: "you have an…

In general PCR tests are highly sensitive. Even smallest viral loads can be detected (Edit) added in general above due to valid points in the comments below

They're highly sensitive to the presence of the target DNA or RNA sequence in the sample well. But they can't easily tell if the target sequence they amplified came from the patient's sample or from other potential sources of contamination in the lab (the test, after all, makes billions of copies of the target DNA sequence), whether from other positive tests or from positive controls.

Re: Mystery in Wuhan: recovered coronavirus patients test negative then positive

#46

> They all requested anonymity when speaking with NPR because those who have challenged the government's handling of the outbreak have been detained. We need to be more hesitant to praise their pandemic response

Came here to quote the exact same line. This right here is why you can't trust the CCP.

Re: Mystery in Wuhan: recovered coronavirus patients test negative then positive

#47

> They all requested anonymity when speaking with NPR because those who have challenged the government's handling of the outbreak have been detained. We need to be more hesitant to praise their pandemic response

The Communist Party enjoys the luxury of dissent being a punishable offense. The media, the citizenry, the private sector are all held hostage by the absolute authority of the Party.

I'm not sure why, but the media seems so eager to accept the official CCP narrative and take the lack of clear dissent from within China to mean China should be held up as a model Nation worthy of praise while simultaneously ignoring all the restrictions and brutality that force silent those who otherwise might have much to complain about.

Deference to China by naive journalists and other useful idiots must be checked.

Re: Mystery in Wuhan: recovered coronavirus patients test negative then positive

#48
post #44

Literally false positive and false negatives. In other words, if you test millions of people, there will be more people tested positive who DON'T have the disease vs. those who test positive and HAVE the disease.

Exactly! For any medical tests, there are 2 measurements: sensitivity and specificity, one to judge false positive and another judge the false negatives. https://en.wikipedia.org/wiki/Sensitivity_and_specificity

Spain sent testkits back to China because they were unreliable

Re: Mystery in Wuhan: recovered coronavirus patients test negative then positive

#50

> They all requested anonymity when speaking with NPR because those who have challenged the government's handling of the outbreak have been detained. We need to be more hesitant to praise their pandemic response

I don't understand this. I haven't seen "praise"? I have seen realistic assessments of the ultimate effectiveness, but I see this as vastly different from "praise".

I think the majority of people in the US that have observed how they handle it see their approach as overly harsh.

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