The COVID-19 pandemic

[danbrotherston]

It means the context of previous data is lost, the previous data is still valid, just in a different context...

The biggest problem is this change in context was not explained, and as a result, you get newspaper headlines like the ones I posted, which has the potential to increase panic.

The problem with continuing to report with the same methodology is that the context of that data has changed as well, so you can't interpret the results under the old methodology the same either. In fact, continuing to use that methodology could result in the public understanding that the situation is far less severe than it is. In that situation, then, you have to ask if waiting for confirmation of results from the National Laboratory better reflects the situation, or if using the preliminary results does.

I am not suggesting that they should have kept the old methodology. But they have done a disservice by changing methodology without explaining it, and the reasoning behind it clearly.

[MidTowner]

It means the context of previous data is lost, the previous data is still valid, just in a different context...

The biggest problem is this change in context was not explained, and as a result, you get newspaper headlines like the ones I posted, which has the potential to increase panic.

The problem with continuing to report with the same methodology is that the context of that data has changed as well, so you can't interpret the results under the old methodology the same either. In fact, continuing to use that methodology could result in the public understanding that the situation is far less severe than it is. In that situation, then, you have to ask if waiting for confirmation of results from the National Laboratory better reflects the situation, or if using the preliminary results does.

Testing is not really being done in order to track the spread of the virus. We don't have the capacity for that kind of testing, so testing is being done to inform decisions about treatment of individual patients. The total results don't bear much relationship (or, anyway, a definable relationship) to the real number of cases.

It's also true that the methodology has changed, so it's hard to even get a sense of the rate of increase.

Based on computer modelling, Ottawa's chief medical officer of help estimates the real number of cases in Ottawa at around 4000.

[tomh009]

Based on computer modelling, Ottawa's chief medical officer of help estimates the real number of cases in Ottawa at around 4000.

That's not quite correct. She did not estimate it at 4000.

"What's more, Etches said computer modelling suggests as many as 4,000 people could be infected across the city."

That indicates a considerably lower confidence level. In the end, no one can say how many people are infected until we actually start doing some random testing. And that's unlikely to happen until things calm down.

[tomh009]

Very troubling situation at St. Mary's Hospital. https://kitchener.ctvnews.ca/dozens-of-n...-1.4862996

Six people have been tested. Doesn't sound quite as bad as the original report, although it's possible other people will yet need to be tested.
https://kitchener.ctvnews.ca/six-staff-m...-1.4863483

[MidTowner]

Based on computer modelling, Ottawa's chief medical officer of help estimates the real number of cases in Ottawa at around 4000.

That's not quite correct. She did not estimate it at 4000.

"What's more, Etches said computer modelling suggests as many as 4,000 people could be infected across the city."

That indicates a considerably lower confidence level. In the end, no one can say how many people are infected until we actually start doing some random testing. And that's unlikely to happen until things calm down.

That's exactly right: No one can say how many people are infected at the moment. But it is certainly higher than the confirmed numbers, and might not even bear much relationship to our confirmed numbers across time. And comparing our numbers to other jurisdictions' is pointless when no one is conducting mass testing, and testing protocols vary widely.

[MidTowner]

Brant County's third confirmed case is someone who works at Cambridge Memorial: https://www.cbc.ca/news/canada/hamilton/...-1.5507341

[tomh009]

That's not quite correct. She did not estimate it at 4000.

"What's more, Etches said computer modelling suggests as many as 4,000 people could be infected across the city."

That indicates a considerably lower confidence level. In the end, no one can say how many people are infected until we actually start doing some random testing. And that's unlikely to happen until things calm down.

That's exactly right: No one can say how many people are infected at the moment. But it is certainly higher than the confirmed numbers, and might not even bear much relationship to our confirmed numbers across time. And comparing our numbers to other jurisdictions' is pointless when no one is conducting mass testing, and testing protocols vary widely.

I agree that comparing absolute numbers has limited value, although it's clear that we have more infected people than Taiwan and fewer than Italy.

But I will argue that the growth rates are still relevant, as long as the reporting and testing methodologies stay reasonably constant. Because a 2.5% daily growth in cases, while still exponential, can be manageable, while 25% will likely stretch a society to beyond its capacity to deal with it. And 30-40% growth rates simply indicate that the situation is out of control. And the rate of positive tests (for example, 2% vs 20%) is also relevant, as long as the testing methodology is also considered.

[tomh009]

Regarding the source of the infections, one thing to note is that while we have significant (voluntary) restrictions right now, last week nearly one million Canadians returned from abroad, explaining how we still have some many infections resulting from travel.

The impact of the social distancing etc will take time to become visible.

[jordan2423]

Probably the last pics for a while. I assume construction will be suspended tomorrow?

Not because of any government action - residential construction is on the "essentials" list.

really, where did you hear this?

[jordan2423]

That's right. There are only two positive tests in the latest batch. I expect some of the 13 presumed positives to be confirmed, but whether it's 1 of 13 or 12 of 13 is anyone's guess.

We can maybe compare this (five total presumed+confirmed cases per day) to the future reports, but, as Dan says, it's not comparable to the previous reports -- or to the Ontario reports, which include only confirmed cases.

A "presumed" case means that they have tested positive but have not yet had the results of the second, confirming test, no?

That is correct Panamaniac.

Presumptive cases indicated they have tested Positive for COVID-19, now they're just awaiting the second laboratory test to confirm it.

[panamaniac]

Not because of any government action - residential construction is on the "essentials" list.

really, where did you hear this?

The list came out this evening.    https://news.ontario.ca/opo/en/2020/3/list-of-essential-workplaces.html 

[jamincan]

[Spokes]

Gotta say I'm surprised by that.

[panamaniac]

Gotta say I'm surprised by that.

I’m more surprised that LCBO, the Beer Store, and weed shops are “essential”.

[tomh009]

Yeah, that pretty much sums it ups. It certainly does not look like a sea change to me.