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Local test positivity rate

Local test positivity rate

Oh Canada
Joined: Mar 2010
Posts: 1392

Oh Canada
Joined: Mar 2010
Posts: 1392

Local test positivity rate
11/20/2020 at 11:00 PM

Adam said "
The Province has issued Friday's COVID-19 bulletin at:
https://news.gov.mb.ca/news/?archive=&item=49879

A death has been reported in the Prairie Mountain Health region, a male in his 80s linked to the Gilbert Plains personal care home outbreak.

A local perspective on data released alongside today’s update is below.

BRANDON:
Total cases on dashboard: 469 (+19 or +108 since November 1)
Active cases on dashboard: 103 (+17)
Recoveries on dashboard: 365 (+2)
Deaths: 1 (no change)

It was stated that the outbreak at Fairview Personal Care Home in Brandon is at 18 cases.

The increase of 19 in Brandon is the highest in data in nearly three months (August 29).

PRAIRIE MOUNTAIN HEALTH REGION:
Reported new cases: 27
Total cases on dashboard: 892 (+25 or +260 since November 1)
Active cases on dashboard: 247 (+19)
Recoveries on dashboard: 637 (+5)
Deaths: 8 (+1)
Current Hospitalizations: 6 (no change)
ICU patients: 1 (no change)

Compared to yesterday, these are the differences in PMH case breakdown by age group in differentiating provincial data released yesterday vs today:
90-99: +5 female, +1 male
80-89: +5 female, +2 male
70-79: +2 female, + 1 male
60-69: +1 male
50-59: +1 male
40-49: +1 male
30-39: +2 female, +2 male
20-29: +1 male
10-19: +1 female, -1 male
0-9: +1 male

In Manitoba as a whole, the province is reporting 438 new cases of COVID-19 and a five day test positivity rate of 13.7% in Manitoba.
"
Hey Adan Would there be a way to show the test positive rate for Brandon and also Prairie Mountain health? Is the data to determine this available?
Adam

Joined: Mar 2005
Posts: 15663

Adam
Joined: Mar 2005
Posts: 15663

Positivity rate
11/21/2020 at 9:19 AM

Not disclosed. What Dr. Roussin did say on I believe Thursday (paraphrasing, maybe someone else that was listening can add) was that in this region, our positivity rate was in the vicinity of what it was when our previous restrictions were put in place during the summer outbreak we saw. This will be a moving target... with the 19 new Brandon cases announced yesterday and the size of the outbreak at Fairview I'll guess that the arrow is pointing up at the moment.

This isn't positivity rate... but for a little more context on where we're at as a city, this graph plots the daily increase in case counts for Brandon that has shown up on the provincial dashboard going back to when they started releasing Brandon data in mid-August.
Abbysmum
Joined: Mar 2009
Posts: 5039

Abbysmum
Joined: Mar 2009
Posts: 5039

I heard that too
11/21/2020 at 11:32 AM

Adam said "
Not disclosed. What Dr. Roussin did say on I believe Thursday (paraphrasing, maybe someone else that was listening can add) was that in this region, our positivity rate was in the vicinity of what it was when our previous restrictions were put in place during the summer outbreak we saw. This will be a moving target... with the 19 new Brandon cases announced yesterday and the size of the outbreak at Fairview I'll guess that the arrow is pointing up at the moment.

This isn't positivity rate... but for a little more context on where we're at as a city, this graph plots the daily increase in case counts for Brandon that has shown up on the provincial dashboard going back to when they started releasing Brandon data in mid-August.
"
I think I heard that too. I do distinctly recall that at our peak in August, we were just above 5%. So that gives some context.

He doesn't routinely give TP% for different regions with the exception of Winnipeg, mostly due to the smaller sample sizes. On one hand, I understand that (if your population is smaller, a single positive case has a much bigger impact on the number than in a larger group), but on the other, it's a good gauge for us to know how much it's circulating. We know the rate is lower here in Westman, but how much lower? It helps us assess risk.

Knowing that we're pretty much back were we started in August is both alarming and unsurprising. Unless we collectively pull up our socks, it will only get worse.
Summertime
Joined: Jul 2010
Posts: 931

Summertime
Joined: Jul 2010
Posts: 931

Steinbach 40% TP rate
11/21/2020 at 11:49 AM

Steinbach Mb reports 40% test positivity rate. While not local, these numbers will undoubtedly effect our community as COVID+ cases will be admitted to PMH as southern health beds reach capacity.
https://globalnews.ca/video/7475272/coronavirus-steinbach-manitoba-reports-40-per-cent-covid-19-test-positivity-rate

Edited by New times, 2020-11-21 11:52:43
Adam

Joined: Mar 2005
Posts: 15663

Adam
Joined: Mar 2005
Posts: 15663

Steinbach
11/21/2020 at 12:00 PM

New times said "Steinbach Mb reports 40% test positivity rate. While not local, these numbers will undoubtedly effect our community as COVID+ cases will be admitted to PMH as southern health beds reach capacity.
https://globalnews.ca/video/7475272/coronavirus-steinbach-manitoba-reports-40-per-cent-covid-19-test-positivity-rate

Edited by New times, 2020-11-21 11:52:43"
That and connections between this community and Steinbach are more than I suspect some realize. I know of a wedding that took place in Steinbach towards the end of October (before the shift to red) with a guest list of more than 80 that included a good-sized local contingent. The Steinbach MLA himself was on that guest list so I’m sure all precautions were taken and we'd be well-past the incubation period of the virus... but we shouldn’t assume we’re an island!
As far as impact on other hospitals of Steinbach's caseload, worth noting that since November 5 there have been nine cases of STARS Air Ambulance being dispatched to Steinbach for what's described as inter-facility transfers according to STARS' Twitter. Can't say by that that they are for sure all COVID-related calls but no other community in Western Canada comes even close to that number of calls over that time frame.
Oh Canada
Joined: Mar 2010
Posts: 1392

Oh Canada
Joined: Mar 2010
Posts: 1392

Test positive rate
11/21/2020 at 12:18 PM

Abbysmum said "I think I heard that too. I do distinctly recall that at our peak in August, we were just above 5%. So that gives some context.

He doesn't routinely give TP% for different regions with the exception of Winnipeg, mostly due to the smaller sample sizes. On one hand, I understand that (if your population is smaller, a single positive case has a much bigger impact on the number than in a larger group), but on the other, it's a good gauge for us to know how much it's circulating. We know the rate is lower here in Westman, but how much lower? It helps us assess risk.

Knowing that we're pretty much back were we started in August is both alarming and unsurprising. Unless we collectively pull up our socks, it will only get worse. "
Correct me if I am wrong the TPR is based on the percentage of those "tested" that turn out positive not the number of positive test to the population of the area.

I assume the 40% rate in Steinbach means that of every 10 people that are tested 4 come back positive on average correct?

If they can determine this for Steinbach and Winnipeg the one would assume they could do it for the second biggest city Brandon and also the prairie mountain health region.
Abbysmum
Joined: Mar 2009
Posts: 5039

Abbysmum
Joined: Mar 2009
Posts: 5039

Yes exactly
11/21/2020 at 12:53 PM

Oh Canada said "Correct me if I am wrong the TPR is based on the percentage of those "tested" that turn out positive not the number of positive test to the population of the area.

I assume the 40% rate in Steinbach means that of every 10 people that are tested 4 come back positive on average correct?

If they can determine this for Steinbach and Winnipeg the one would assume they could do it for the second biggest city Brandon and also the prairie mountain health region. "
That's exactly how it's calculated, and that's exactly what it means. But with smaller test numbers, which there would be in the different regions due to different population sizes, small variations in test and positivity numbers have very different impacts, and is hence considered not as reliable.

If we compare Winnipeg to Brandon, for example, Winnipeg has a population of roughly 784k while Brandon is just shy of 50K. That's roughly a 15-fold difference. Let's assume that on any given day, 1% of the population gets tested (I don't know the actual number, I'm just pulling one out of my hat).

So in Winnipeg, in our example, means 7,850 people are tested, and Brandon has 500 people tested. Both come back at 5% positivity, so Winnipeg has 393 (rounded) positive people, and Brandon has 25 positive people.

If we add just 5 additional positive people to each city, you can see the impact that even small numbers have, proportionally, to the overall numbers when dealing with small samples.

If we add 5 to Winnipeg's total, for 398 positive cases (vs. 393), that results in a test positivity rate of 5.07%

If we add 5 to Brandon's total, for 30 positive cases (vs. 25), that results in a test positivity rate of 6%.

If we added 10 additional cases to each city, it would result in 5.14% vs. 7%, respectively.

So for that reason, they are hesitant to release data on smaller populations because small differences in numbers can skew the percentages disportionally. You can argue that it's irrelevant, as numbers are numbers and even 5 cases is a lot for here (and I would agree with you). But that's the reason they're using to justify not doing it on a routine basis.
Adam

Joined: Mar 2005
Posts: 15663

Adam
Joined: Mar 2005
Posts: 15663

Positivity rate
11/21/2020 at 1:07 PM

Oh Canada said "Correct me if I am wrong the TPR is based on the percentage of those "tested" that turn out positive not the number of positive test to the population of the area.

I assume the 40% rate in Steinbach means that of every 10 people that are tested 4 come back positive on average correct?

If they can determine this for Steinbach and Winnipeg the one would assume they could do it for the second biggest city Brandon and also the prairie mountain health region. "
Abbysmum explains it well by my understanding... if for example 50 are tested in an outbreak situation and 25 come back positive that will have a bigger effect on a region's overall percentage the smaller the region is.
Just personally for my own understanding I'd still like to see data at at least the Prairie Mountain level. With population of over 170k it should be a reasonable sample size. They'd just have to share how many are tested in each region daily and we would have that percentage, but maybe there are other challenges in putting out data that useful.

Seems to vary by province on whether they give testing numbers beyond the provincial level. BC, Alberta and Sask do look like they release test data by region/health authority on their stats pages, but even then it doesn't look like you could expect it to as far down as the city level for a city our size. Ontario and Quebec from what I can see only give daily test data at the provincial level.
Oh Canada
Joined: Mar 2010
Posts: 1392

Oh Canada
Joined: Mar 2010
Posts: 1392

Apples to Apples
11/21/2020 at 1:40 PM

Abbysmum said "That's exactly how it's calculated, and that's exactly what it means. But with smaller test numbers, which there would be in the different regions due to different population sizes, small variations in test and positivity numbers have very different impacts, and is hence considered not as reliable.

If we compare Winnipeg to Brandon, for example, Winnipeg has a population of roughly 784k while Brandon is just shy of 50K. That's roughly a 15-fold difference. Let's assume that on any given day, 1% of the population gets tested (I don't know the actual number, I'm just pulling one out of my hat).

So in Winnipeg, in our example, means 7,850 people are tested, and Brandon has 500 people tested. Both come back at 5% positivity, so Winnipeg has 393 (rounded) positive people, and Brandon has 25 positive people.

If we add just 5 additional positive people to each city, you can see the impact that even small numbers have, proportionally, to the overall numbers when dealing with small samples.

If we add 5 to Winnipeg's total, for 398 positive cases (vs. 393), that results in a test positivity rate of 5.07%

If we add 5 to Brandon's total, for 30 positive cases (vs. 25), that results in a test positivity rate of 6%.

If we added 10 additional cases to each city, it would result in 5.14% vs. 7%, respectively.

So for that reason, they are hesitant to release data on smaller populations because small differences in numbers can skew the percentages disportionally. You can argue that it's irrelevant, as numbers are numbers and even 5 cases is a lot for here (and I would agree with you). But that's the reason they're using to justify not doing it on a routine basis. "
I understand what you are saying . If they are hesitant to release smaller populations the question is if they can release that Steinbach is at a 40% test positive rate then there is no reason they can not do it for Brandon correct? Test positivity rate is the key rate I think they are using to determine the need to implement more restrictions or less and in what regions correct?
LukeD
Joined: Jun 2017
Posts: 72

LukeD
Joined: Jun 2017
Posts: 72

TPR is
11/21/2020 at 1:57 PM

one of the indicators to a rise in community transmission. There's a lot of other factors
- a rise in outbreaks at workplaces, community events, gatherings etc
- a general rise in positive cases
- a rise in symptomatic cases that require to get tested
- rise in deaths

Restrictions are based on multiple factors, some of which might not be easily available for release to the public.

When Brandon had the outbreak back in August, I was interacting with PH regularly and they can get overwhelmed really fast. From contact tracing to case management to data management and reporting. It's a lot of work and I wouldn't expect all the facts and data to be readily available to the public. It's unfortunate but the nature of the situation we're in.
Grammie
Joined: Nov 2009
Posts: 33

Grammie
Joined: Nov 2009
Posts: 33

Sadly, you're wrong!
11/21/2020 at 2:03 PM

Adam said "
That and connections between this community and Steinbach are more than I suspect some realize. I know of a wedding that took place in Steinbach towards the end of October (before the shift to red) with a guest list of more than 80 that included a good-sized local contingent. The Steinbach MLA himself was on that guest list so I’m sure all precautions were taken and we'd be well-past the incubation period of the virus... but we shouldn’t assume we’re an island!
As far as impact on other hospitals of Steinbach's caseload, worth noting that since November 5 there have been nine cases of STARS Air Ambulance being dispatched to Steinbach for what's described as inter-facility transfers according to STARS' Twitter. Can't say by that that they are for sure all COVID-related calls but no other community in Western Canada comes even close to that number of calls over that time frame.
"
I know a young lady that was invited to this wedding and chose not to go. She watched the live stream and was horrified to see that the only people wearing masks were the people serving the food. No wonder Steinbach is in such a dire situation.
Abbysmum
Joined: Mar 2009
Posts: 5039

Abbysmum
Joined: Mar 2009
Posts: 5039

Well...
11/21/2020 at 4:29 PM

Oh Canada said "I understand what you are saying . If they are hesitant to release smaller populations the question is if they can release that Steinbach is at a 40% test positive rate then there is no reason they can not do it for Brandon correct? Test positivity rate is the key rate I think they are using to determine the need to implement more restrictions or less and in what regions correct? "
I don't pretend to speak for those in charge, but I suspect the fact that nearly half of all tests in Steinbach (and a third in outlying areas) coming back positive probably have something to do with it? That a big ration no matter the population size.

Steinbach has had all sorts of issues - between the protests and the overflowing hospital (with people getting triaged in cars, according to the media) and the large-scale refusal of people wearing masks - that maybe it was thought it was prudent to release these numbers.

It's also important to note that while Steinbach has only 1.5% of the provincial population, it has nearly 15% of all deaths, and is a significant source of ICU cases. It impacts us all.

Edited by Abbysmum, 2020-11-21 16:31:10
Adam

Joined: Mar 2005
Posts: 15663

Adam
Joined: Mar 2005
Posts: 15663

Test stats
11/21/2020 at 8:37 PM

I’m on the side of the more data and transparency the better, but it must sometimes be a tough decision by the powers that be on what to release and what not to since some will read into stats improperly, either innocently or to feed confirmation biases. Classic example I saw earlier this month was in a reply on a prominent local Facebook page where someone on the misinfo side of the fence dangerously posted with confidence the false info that since Winnipeg’s test positivity rate was 9.3% at the time and Manitoba’s was 9.5%, Manitoba outside of the perimeter must have next to no Covid based on subtracting the two numbers. That was of course false and based on those stats the rest of the province was higher than Winnipeg to the point of bringing the average up. The concerning part was that before it was deleted the post got a lot of likes from others who read it and obviously wrongly believed that Manitoba outside of Winnipeg was next to nil.

It has to be incredibly frustrating to see stats used dangerously like that, as much as to someone like yourself might find it frustrating to not have all of the data to fully understand present state.

As far as the Steinbach wedding example, I really didn’t want to make this thread about it so much as use as an example that Steinbach and Brandon are more connected than some might think. I’ll admit that even in pre-Red times where it was allowed and with precautions like splitting people into separate rooms it did raise an eyebrow to hear about an inter-city wedding.... but in this case I’d think we would’ve heard about a local cluster from it by now if anything serious came of it. At any rate we shouldn't view that city's off-the-charts positivity rate as being on a separate planet, even though with the hunkering down to Red I'm sure a lot of the lines between the communities will be paused.
nicemoustache
Joined: Apr 2012
Posts: 167

nicemoustache
Joined: Apr 2012
Posts: 167

And
11/21/2020 at 10:57 PM

How do you know who to believe? Some of the numbers we see are certainly unbelievable... both ways. According to the European center for Disease Prevention and Control, China, where this whole thing started almost exactly a year ago is only reporting 91,704 total cases and only 200 in the last 14 days...can we believe that? That’s total is less than 1/3 the cases Canada is reporting, (with almost 65,000 in the last 14 days). Population / density is not comparable. The US is at almost 12,000,000, India is at over 9,000,000, and Brazil over 6,000,000. I’m not sure of the possible advantages or disadvantages of either over- or under-reporting but some of the numbers floating around are suspicious. According to the ECDC site, the Americas (combining North, Central and South) are not reporting a whole lot more daily cases than they were some days in July when Canada was reporting a few thousand /14 days.Regardless of the numbers, we know we have a serious health issue to deal with and at this point I’m not sure if the accuracy is important. Unfortunately, because we haven’t had to deal with this before, we have to learn on-the-go and that’s a difficult thing when lives are at stake. I sure admire our politicians, Drs and health care workers for the job they are doing under incredible pressure from those of us that are much less educated in world of health.
Abbysmum
Joined: Mar 2009
Posts: 5039

Abbysmum
Joined: Mar 2009
Posts: 5039

China
11/22/2020 at 10:03 AM

nicemoustache said "How do you know who to believe? Some of the numbers we see are certainly unbelievable... both ways. According to the European center for Disease Prevention and Control, China, where this whole thing started almost exactly a year ago is only reporting 91,704 total cases and only 200 in the last 14 days...can we believe that? That’s total is less than 1/3 the cases Canada is reporting, (with almost 65,000 in the last 14 days). Population / density is not comparable. The US is at almost 12,000,000, India is at over 9,000,000, and Brazil over 6,000,000. I’m not sure of the possible advantages or disadvantages of either over- or under-reporting but some of the numbers floating around are suspicious. According to the ECDC site, the Americas (combining North, Central and South) are not reporting a whole lot more daily cases than they were some days in July when Canada was reporting a few thousand /14 days.Regardless of the numbers, we know we have a serious health issue to deal with and at this point I’m not sure if the accuracy is important. Unfortunately, because we haven’t had to deal with this before, we have to learn on-the-go and that’s a difficult thing when lives are at stake. I sure admire our politicians, Drs and health care workers for the job they are doing under incredible pressure from those of us that are much less educated in world of health. "
I think I've one of the few people on this planet that actually kindasorta believes the Chinese numbers. Why? Because they would weld people into their apartments buildings to keep them from leaving. They will have a handful of cases in a city, and will proceed to mass-test 2 or 3 million people in the space of a few days. They are highly organized, have the manpower to do aggressive contact tracing and follow-up/enforcement and have the technological and manufacturing ability to produce sufficient PPE and testing equipment.

Their society is highly rigid, the rule of the party is almost absolute, they generally obey rules/orders (there are noteable exceptions), and we've all seen the pictures of life there being more or less normal.

The disease might have originated there, but they geuinely do seem to have a handle on it.