Player positive now negative

[pete 318]

The Norwich player tested positive after Spurs game has had another test and tested negative needs further test.  If true and it is confirmed not positive this must put some doubt into the organisation doing the testing can any test really be trusted.  Questions need to be answered.

https://www.bbc.co.uk/sport/football/53064831

[Matt Juler 148]

There will always be a level of false positives in this sort of screening, hopefully that is the case here.  More concerning would be a case of mistaken identity where labeling or the sample got mixed up and we have Player A negative in isolation and Player B positive in team training.

[Making Plans 936]

There are Positive Positives, Positive Negatives, Negative Positives and Negative Negatives

[paddycanary 538]

9 hours ago, Making Plans said:

There are Positive Positives, Positive Negatives, Negative Positives and Negative Negatives

almost 'Rumsfeldian!'

[C.I.D 302]

13 hours ago, Making Plans said:

There are Positive Positives, Positive Negatives, Negative Positives and Negative Negatives

Not being negative but.............how positive are you about this ? 🙃

[The Great Mass Debater 1,076]

Coronavirus testing is done by nasopharyngeal swab. Firstly this potentially introduces a sampling bias, as the swab may simply not have been done properly, so false negative rate is suspected to be higher than the official rate.

Secondly, this method has been shown to be only 50% accurate if undertaken after 5 days from the point of infection (ie when they have retested known cases at the 5 day point, up to 50% subsequently test negative. This probably simply represents the body clearing the virus.

The player in question testing negative now probably simply means his body has almost cleared the virus/his infection was acquired over 5 days ago. It could potentially mean a false positive, but false positive rate is lower than false negative rate.

So him now testing negative really doesnt mean anything and is rather expected.

If we truly wanted to know whether the player had the infection (though why that is relevant is debatable) he would need the blood anti-body test, which Roche claims is 100% Sensitive and 100% Specific. I personally am suspicious about that. It is also unclear how long it takes for antibodies to form, or indeed how long they last for (not to mention whether this confers any immunity)

[keelansgrandad 6,679]

2 hours ago, The Great Mass Debater said:

Coronavirus testing is done by nasopharyngeal swab. Firstly this potentially introduces a sampling bias, as the swab may simply not have been done properly, so false negative rate is suspected to be higher than the official rate.

Secondly, this method has been shown to be only 50% accurate if undertaken after 5 days from the point of infection (ie when they have retested known cases at the 5 day point, up to 50% subsequently test negative. This probably simply represents the body clearing the virus.

The player in question testing negative now probably simply means his body has almost cleared the virus/his infection was acquired over 5 days ago. It could potentially mean a false positive, but false positive rate is lower than false negative rate.

So him now testing negative really doesnt mean anything and is rather expected.

If we truly wanted to know whether the player had the infection (though why that is relevant is debatable) he would need the blood anti-body test, which Roche claims is 100% Sensitive and 100% Specific. I personally am suspicious about that. It is also unclear how long it takes for antibodies to form, or indeed how long they last for (not to mention whether this confers any immunity)

So is there the possibility that any of those that tested negative can in fact be positive?

[GenerationA47 746]

5 minutes ago, keelansgrandad said:

So is there the possibility that any of those that tested negative can in fact be positive?

With the usual tests, studies are showing that 20-30% of negative results are false.
 

Govt do not talk about this much (or that 40-50% of infected cases will never show symptoms)

Edited June 17, 2020 by GenerationA47

[Wacky Waving Inflatable Arm Flailing Tube Man 3,776]

Just now, GenerationA47 said:

With the usual tests, studies are showing that 20-30% of negative results are false.

So about six of our squad actually have the virus?

[GenerationA47 746]

2 minutes ago, Wacky Waving Inflatable Arm Flailing Tube Man said:

So about six of our squad actually have the virus?

Hmmm!

[CANARYKING 634]

Confirmed Stiepermann 

[The Great Mass Debater 1,076]

42 minutes ago, keelansgrandad said:

So is there the possibility that any of those that tested negative can in fact be positive?

Absolutely. In patients we strongly suspect of having Coronavirus we have been recommending they have a second swab if the first is negative. Two false negatives is statistically improbable

[The Great Mass Debater 1,076]

38 minutes ago, GenerationA47 said:

Govt do not talk about this much (or that 40-50% of infected cases will never show symptoms)

Most estimates I have seen (and bear in mind they are only estimates, noone really knows) have put the asymptomatic percentage at around 80%. This is why the "I feel fine, I'll take my chances" approach of some is is misguided. Its not about you, its about who you might be spreading it to unknowingly, who then might not be fine.

For anyone interested, it's not actually the virus that does the damage, it's the body's reaction to it. I think of those who have had severe symptoms in the same way I think about allergies. For instance most people can take penicillin. Some will have a bad reaction. Some could have such a bad reaction they die. The virus itself isnt too different from a cold virus - where the difference lies is the immune response. The virus is cleared by the body after about 7 days. There is about a 7 day incubation period. This is why the self-isolation period is set at 7 days for symptomatic patients (you can come out of isolation on day 7 without fear as you will be clear of the virus) but 14 days for cohabitants (as they have a potential 7 day incubation period before a 7 day symptomatic period).

The damage (namely pulmonary infarction on a massive scale) comes about through something called 'cytokine storm', and it happens to people on an individual scale. Co-morbidities such as lung conditions and diabetes etc increase your risk, but anyone can become ill.

This brief article on cytokine storm explains it really well. https://www.newscientist.com/term/cytokine-storm/

[keelansgrandad 6,679]

Thank you GMD. I think that is the clearest information I have had about the virus from any source. We need you at the briefings.