Although the test kits they use are new, the technique is really basic molecular biology.
I would liken these kits to buying a Betty Crocker cake mix. They take the thinking out of it. They literally say add chemical labelled A to bottle labelled B. If you get the temperature wrong on your oven, bit clumsy with your mixing, or store the ingredients in hot warm conditions you could stuff it up. But it generally should work.
However there are thousand of bakers up and down the country who dont need a Betty Crocker cake mix. They have baked cakes thousands of times. it may seem absurd, but these kits are not more special than a cake mix (packaged nicely at produced at scale). I could literally design my own custom Covid kit in a few hours on my home PC, and get it mail ordered delivered within 48 hours. I have done this thousands of times for thousand of microorganisms.
The technique is well established, very reliable and very easy to do (One of the first experiments taught at university lab classes). The best way of thinking of Shaqiris test, is not that the testing failed. But that it was too good. Despite him having Covid-19 in the past, the test was so sensitive it could detect the small amount of virus genetic material remaining.
Unless they are buying dodgy Chinese kits, the greatest source for error is likely not to be at testing but at collection. Mislabelling, cross contamination, poorly trained and not properly swabbing.
Yes, so perhaps supports the idea that the numbers might be being inflated by false positives such as Shaqiri - in that the test is picking up historic traces even if the player isnât currently suffering or contagious?
It was a deal joke, the original post was just before a game and had an error listing Mane starting his quarantine on the 9th October, as it hadnât started yet we could have played him. Rubbish joke that now looks even worse now the dates have been updated/corrected!
No. That is not what is meant by a false positive. But it does point to a reality of a certain percentage of positive cases being subclinical.
I posted about this a couple of weeks ago about the growing evidence of this being a significant number of the cases. Furthermore, this might be one of the beneficial effects of routine mask wearing in that people who get infected while wearing a mask are likely to get a lower viral load and less or no symptoms.
Surely a test saying that a player is currently infected with coronovaris when they arenât is a false positive regardless of whether itâs picking up traces of a previous infection or not?
Your point is a fair one, but when talking about lab diagnostics, typically the focus is on analytic rather than clinical performance. So in that sense a false positive would be viewed as one in which the wrong molecule was flaggedâŚthink cross reactivity with a different coronavirus like a cold virus. You also have considerations for, in ISMFâs analogy, lab techs who bake the cake incorrectly.
But in short, even with a test that works exactly how it is supposed to, there are going to be people who test positive with little clinical relevance to the test. There are growing signs that this is a higher number than we thought, but there just isnt enough known about it yet to really get a handle on it all.
I designed my emergency covid test in one night having the lab to run it is the problem.
Also, there are a number of cases reported in which a âre-infectionâ is detected with PCR (a person who is tested positive, isolate >14 days, tested negative, then tested positive again). It isnât that the virus can return and infect the same person, itâs just that the sensitivity (or lack of) of the test isnât ideal for the current situation. I wonder if they also use some kind of antibody test. In any case, still having players flying all over the world right now just for a possibly delayed World Cup/whatever international cup is plain stupid. I donât even know who will be responsible for all this.
There is now clinical proof that reinfections can happen, there are reports of people coming down worse second time around so either they never had it all or they are reinfected.
You canât come down with it worse second time if itâs a lingering former version of it.
Though it does open the door to the fact you canât be immune to it once youâve been infected.
Of all the patients reported âre-infectionâ in my country, no further symptoms were observed and culturing samples from these patients yielded no viable virus. But their PCR results were still positive even after 3 months (which âsome peopleâ kept quiet about).
But I also have seen the paper from Lancet regarding âreinfectionsâ. Very interesting and worrying at the same time. Previous reports of reinfection were all disregarded due to no proof of infectivity in those cases.
The report from Nevada is more interesting for itâs details below⌠We donât really know how this developments and mutates, we know a lot but we also know very little and it is a lot of guess work based on what we know.
having the lab to run it is the problem.
