The last 72 hours testing has produced 1,895 positives.

In the same period, 1,459 cases were announced.

So you might wonder what is going on with the difference of 436. I don't know for sure but there is one strong likely explanation, and it is a long answer:

The first thing to understand is a positive test =/= a case.

When you mass test hospital staff, nursing homes on a weekly or fortnightly basis you get a very small % who have a 2nd consecutive positive test.

That doesn't account for much more than a 0.3% difference.

The same goes for patients in hospitals and close contacts, although in hospitals people can have 3 consecutive positives. Some in NY hospitals had 7 or 8 consecutives.

You would always tend to test a patient more than once, days apart, to reduce the impact of false positives.

The issue with all of this is that the ratio of positives:cases was running in the high 90's.

So it was relatively safe to ballpark new cases by assessing positives in real time.

And yet, if this is still the situation, we are missing 400 cases. Why?

One possible explanation for all of this is you're going to find one day - possibly tomorrow or Saturday - where there is an enormous case load announced.

This isn't some nefarious scheme to scare anyone.

It's a natural consequence of a rising positivity rate.

The recording system used in Ireland is CIDR, in Sweden it's SmiNet, in Spain it's CNES.

All of these rely on complicated manual inputs of data and case validation.

You try to be sure that a positive correlates to a new case before you notify it.

This is a very time consuming process, so much so that many countries abandoned giving updates on Sunday and Monday - and some even on Tuesday.

Because when cases rise quickly - but staffing levels stay constant - it takes a lot longer for the entire process to play out.

As a result you tend to get a Tuesday effect.

Monday tends to be artificially low and Tuesday artificially high, when they catch up from the weekend.

But increasingly in Europe that is turning into a Friday effect, sometimes Saturday in places.

So, my best guess is we will see a day soon of 800 to 1,000 cases announced.

It will shock people but the reality will be lower and that's why 5-day and 7-day trends are important metrics to keep track of, as they help mitigate/eliminate these data validation delays and lags.

Last 24 hours:

Tests: 15,880
Positives: 754
Negativity rate: 95.24%

Cases announced today: 506

So that's a pretty huge disparity and will probably lead to the Friday effect.

So the bottom line here is you have to understand the infectious disease reporting systems in Europe rely on manual inputs.

There is a finite number of overworked people doing it, when cases suddenly rise, it leads to lag time because every 1 person is now doing twice the work.

I talk to Public Health people daily. Some depressed, some shattered, others so burned out you worry for them existentially.

The only way the public can help them is to reduce the case loads they are dealing with and try to support any initiative to get them more resources.