The link between the level of testing and the confirmed cases

Brendan Burgess

Brendan Burgess

Founder
Messages
52,185
212 new cases today.

Does this reflect a lower rate of infection or is it something to do with the testing.

On the RTE news, George Lee said that we are doing the same amount of testing but the percentage positive has risen. On reflection, this makes no sense.

They really should publish the number of tests finalised each day and how many of them are positive.


Brendan
 
Last edited:
Brendan Burgess said:
212 new cases today.

Does this reflect a lower rate of infection or is it something to do with the testing.

On the RTE news, George Lee said that we are doing the same amount of testing but the percentage positive has risen. On reflection, this makes no sense.

They really should publish the number of tests finalised each day and how many of them are positive.

Brendan
Click to expand...
I think it’s because of testing issues, based on anecdotal reports though. I agree with you that some of the reports make no sense. I think the media is sometimes influenced by the need not to panic people and the reports skim the facts too much.
 
DeeKie said:
I think the media is sometimes influenced by the need not to panic people and the reports skim the facts too much.
Click to expand...

Agreed, the obvious downside of this is that the public will lose trust in the media and the authorities. The big danger then is that some people are less likely to carry on following all the guidelines/rules into the future.

Very important for the authorities to be open with information. That's why they should include the number of tests they're reporting on daily as Brendan has suggested.
 
Last edited:
Brendan Burgess said:
They really should publish the number of tests finalised each day and how many of them are positive.
Click to expand...
Agree with this Brendan. It would also be useful to know how many tests are in the lab queue (i.e. the tests have been taken and are awaiting processing). It sounds like there may be a 10+ days of a backlog currently so it means the numbers we are getting each day are very old numbers. It would be good to know these numbers so that we can see if they are dropping or increasing each day.
 
Ceist Beag said:
it means the numbers we are getting each day are very old numbers.
Click to expand...

I hadn't thought of that.

So does that mean that the 200 cases yesterday are from 10 days ago?

They are arguing, with huge caveats, that the rate of growth is down from 30% a few weeks ago to 15% today.

But should this all be stepped back by 10 days? The rate of growth was 15% 10 days ago and might be much lower again now?

Brendan
 
It's hard to know tbh Brendan. On the one hand you hear (and I this to be true from a number of people) that test results are taking 10+ days to process. On the other hand you hear that there is prioritisation of which tests are processed. So some of the 200 yesterday may be from tests taken 10+ days ago while others may be from more recent tests. WIthout the numbers we're only guessing but I do think it would be good to know these things.
 
As said on another thread, the numbers are strange and there are many on-point comments in this thread. So just to add,

1. It's hard to comment on the shape of the curve with incomplete data

2. Regarding the decrease in the rate of growth, is the following not what's happening (not actual figures - just to illustrate the concept) given the ceiling in the number of cases processed?

DayOpening New TotalIncrease
x1,0002501,250
25%​
x+11,2502501,500
20%​
X+21,5002501,750
17%​
x+31,7502502,000
14%​
x+42,0002502,250
13%​
x+52,2502502,500
11%​
x+62,5002502,750
10%​
 
With the changes in testing eligibility criteria and time to get results changing not sure can draw much from numbers of new cases.
The key is R0 the number infected from each infected case which must be falling if number contacts greatly reduced .
 
I would think we will have serious spike in numbers with German labs coming on board to catch up . Impossible to know where our numbers are at or what they are testing a day.is it 1500 results we get, how many swabs are taken.
What is backlog?
It also wasn't hard to read between lines of disaster in nursing homes secrecy is not the answer here.
 
Testing numbers from Paul Reid:
Last week 2,000-2,500 per day, dropping to 1,500 per day towards end of week.

Hope to do 4,500 per day next week
 
The more I think about it, the less useful the confirmed cases figure is.

Imagine a situation where the true number of cases in the population was increasing by 50% a day. But they stopped testing completely. The confirmed cases would drop to 0.

Likewise, if we have a situation with few new cases, but the level of testing increases from 1,500 to 4,500, there will be tripling of confirmed cases.

And, of course, if the German labs send back 10,000 results on the one day, with a 15% positive rate, there will be an increase to over 1,500 confirmed cases that day.

Brendan
 
Although, I think the figure as reported is not very useful, it is a very important measure if they did it properly.

Brendan
 
The confirmed cases figure is completely arbitrary. They don’t have enough test kits and they don’t have enough reagent in the labs.
“Test, test, test”, said the WHO.
“Yes, we will”, said Ireland.
Then Ireland changed their testing criteria because they couldn’t handle the numbers they were meant to test.
My wife was tested on a Sunday morning and she said it was shambolic. The following days she was confirmed positive. Then, as I’d the same symptoms as her, I was put I the testing list. After five days I’d heard nothing so I phoned the HSE. I was told “if you were told you’re on the list, then you’re on the list”.
Five days later the Irish test criteria had changed, and after another five days I’d recovered.
When I read about COVID-19 I totally ignore the number of cases because it’s irrelevant. The number of deaths, and the deaths per million, are the only figures that matter. And R0, but thats a harder one to quantify.

Sweden, where there is no lockdown and life is largely normal, only test those being admitted to hospital.

I think such widespread testing, and efforts to test, is a waste of resources in the midst of a crisis.
 
Paul Reid:

Previous backlog of 35,000 tests
Down to 11,000 tests now. Will be completed this week.

7,900 tests completed on Saturday

Current hospital tests taking 24-36 hours to complete. Community testing takes longer.

72,000 tests completed now
 
Last edited:
You must log in or register to reply here.
Back
Top