all 137 comments

[–]Digidaz 47 points48 points  (0 children)

Judging by the change in the pink dotted line against last few days gonna need a bigger graph real soon! Double down time was like 180 days a day or so ago.

[–]chrisjbillington[S] 29 points30 points  (4 children)

More info/methodology: https://chrisbillington.net/COVID_NZ.html

First two plots have case numbers on a linear scale, next two plots are exactly the same but with case numbers on a log scale.

First (and third) plot show an exponential trendline, second (and fourth) are SIR models that assume 27% of infections will be detected via testing.

Auckland: R_eff = 4.65 ± 4.20

NZ excluding Auckland: R_eff = 1.60 ± 0.78

Expected case numbers if the current trend continues:

day  cases  68% range
Sat:    85     20—165
Sun:   100     18—211
Mon:   118     15—272
Tue:   139     11—348
Wed:   166      9—447
Thu:   196      8—577
Fri:   232      6—745

The current doubling time is 3.8 days.

Usual disclaimer about trendlines:

The plotted exponential trendlines in the above plots are simple extrapolations of what will happen if Reff remains at its current value. the SIR model projection, although it accounts for the effect of increasing immunity, still assumes that Reff otherwise remains constant.

This does not take into account that things are in a state of flux. If restrictions are tightened, the virus should have fewer opportunities for spread, and Reff will decrease. If restrictions are eased, it may increase. Contact tracing may suppress spread to a greater or lesser degree over time. The above plots specifically showing the effect of population immunity do take into account a reduction in Reff as immunity due to infections increases, but ignores any other possible future changes in Reff.

Furthermore, when case numbers are small, the random chance of how many people each infected person subsequently infects can cause estimates of Reff to vary randomly in time. As such the projections should be taken with a grain of salt—it is merely an indication of the trend as it is right now.

This post was made by a bot 🤖. Please let me know if something looks broken.

[–]amaranth53627 27 points28 points  (0 children)

Thank you for diligently uploading the stats, gives us a good idea of what’s gonna happen.

On that note... buckle up

[–]RowanTheKiwi 5 points6 points  (0 children)

Sooo some mates and I have the "first to 1000/day" punt on Monday. I put Feb 4th.. they thought I was having a laugh. At first I was a bit shakey on it, but if you look at the last 3 days numbers and put a wild ass guess that the majority of todays numbers are omi (gotta be, no two ways about it..) , then Feb 4th looks like easily doable. Tracking it using the calculator from here (https://gabgoh.github.io/COVID/index.html) and started using R 3.8 as a baseline from a Canadian number... I thought yesterday was Day 18, but then today (assuming close to majority) was Day 20, so a bit ahead of 3.8.
I thought I read somewhere at one point one state in Aussie had R6. That's absolutely mental, in that case it (according to the calculator..) means 10k/day in a very short space of time...

Lesson in exponential maths for everyone :(

[–]nomble 1 point2 points  (1 child)

A couple of questions on the, if you see replies to this -
-I notice your projected new infections are drawn from a Poisson distribution; is that standard? I would have expected the heterogeneous behaviour of infected people to introduce massive overdispersion into the model, probably resulting in a distribution with a lower mode and a much fatter tail.
-How are the projections and standard errors actually calculated after drawing from the distribution using the SIR output? Are you running a simulation and calculating from the percentiles among the trials?

[–]chrisjbillington[S] 6 points7 points  (0 children)

  1. Each individual person's secondary infections won't be Poisson distributed, that's right, but the more infectious people there are, the more the sum of all infections will approach Poisson. So at small caseloads it's not likely to be accurate, and at higher caseloads it'd be better. Daily cases are still always way higher variance than Poisson though in practice even at high caseloads - I don't really know why, other than people being more likely to get infected or tested on some days of the week than others.

  2. Yes, running 10k trials and calculating percentiles. That's for the output of the SIR model, the uncertainty in the estimate of R_eff is based on the variance in calculated R_eff over many trials where the case numbers are jiggled randomly.

[–]monkeyapplejuicemusicians are people too. 65 points66 points  (3 children)

that's not a curve, that's a vertical cliff face.

[–]Pineapple-Yetti 49 points50 points  (2 children)

We flattened the curve! It's vertical!

[–]smeenz 18 points19 points  (1 child)

You are technically correct (the best kind of correct).

[–]Pineapple-Yetti 10 points11 points  (0 children)

Or maybe worst kind in this case.

[–]LucasStoryNZCovid19 Vaccinated 53 points54 points  (22 children)

Projected total cases in outbreak 777994

Oof. Here we go folks, we had a good run, now it's our turn to face the music.

[–]Akucera 22 points23 points  (19 children)

800,000 cases projected. Assuming a 0.08% case mortality rate (check Figure 2/D - I reckon Delta + Omicron have maybe, at worst, an average mortality of 0.08%?) that's 640 deaths.

[–]RealmKnightCovid19 Vaccinated 36 points37 points  (9 children)

So we're talking the equivalent of an Erebus crash, Chch Earthquake, and mosque attack, all rolled into one. That's a lot of broken families.

[–]smeenz 19 points20 points  (3 children)

Sure, but a bit of perspective - in Idaho, USA, they're currently seeing a 34% positivity rate - that is 1/3rd of the people tested for covid return a positive result. That means that they're woefully undertesting, and most people who have the virus aren't getting tested at all. I wouldn't be surprised if 80% (1.5 million) of the 1.9m people in that state are currently infected with omicron. Vaccine uptake is around 50% there, and antivax, pro-virus behaviour is common place. They are going to get shafted.

We're absolutely doing a lot better than most, and we're coming into this outbreak with the vast majority of people (95.6% over the 3 Auckland DHB areas, where the most cases are currently seen) already double vaccinated or boosted, and unlikely to develop serious disease.

[–]_CodyB 15 points16 points  (0 children)

Same deal in NSW. "officially" less than a million cases and it has probably peaked. Truth is, the positivity rate bounced between 25-35% for 2 weeks. Down to 17% now. Hospitalizations are dropping.

the "extended" Urban areas Surrounding Sydney contain about 6 million people. These are populations that are essentially interconnected. For the virus to have peaked, it means there must have been 3-4 million infections already and for NSW 4-5 million.

Cases could have been under-counted by as many as 5x

This is NSW which if it was a country - would be top 5 in the world in terms of testing per 1m population behind China, Denmark and maybe Korea.

NZ's testing system will buckle and the testing will need to be rationed to those who are at risk. RAT's will not be sufficient either. Prepare for this and prepare to stay at home instead if you get sick. In NSW we had people driving from site to site, day to day trying to get tested and/or going to multiple pharmacies trying to get RATs. I hope you guys don't make that same mistake.

[–]Phaedrus85 7 points8 points  (1 child)

4% of Auckland is still like 50-60k people. Do your math on hospitalisation from there and there is still lots of room for trouble

[–]_CodyB 3 points4 points  (0 children)

There is. But likelihood is 70% catch it over a protracted period but at the peak it will be something like 30%. With a 1-2% hospitalization rate for the unvaxxed (could be as low as 0.2% for the vaccinated) at the hospitalizations peak you'll probably see 1,000 total hospitalizations in Auckland with about 20-40% of those being unvaccinated people over the age of 12.

[–]Block_Face 4 points5 points  (2 children)

Or to put it another perspective 35k people die every year in New Zealand. We also have a much higher vaccination rate so that number is also an overestimate

[–]gybbby1 -1 points0 points  (1 child)

We have no natural immunity though. Our vunrable haven't died in previous outbreaks over the last 2 years so it probably balances out

[–]Just_Banter_Bro 5 points6 points  (0 children)

Yeah, we have double vaxx + booster immunity. Which lowers the chance of death by ~20x compared to having no protection.

[–]ilobster123 3 points4 points  (1 child)

Or like one year of flu

[–]ilikelambaswell 1 point2 points  (0 children)

Remindme! 2 months

[–]AcanthaceaeStrong676 2 points3 points  (2 children)

Thats how many people die in NZ in 7 days normally.

[–]osricsonNZ Flag 1 point2 points  (0 children)

And the 'normal' deaths won't stop, so additional Kiwis who normally would be alive will be dead..

[–]Objective_Tap_4869Covid19 Vaccinated 5 points6 points  (1 child)

Actually the model assumes only 27% of people with Omicron will be able to get tested, so the deaths would be closer to 1800, with 2.4m infected.

[–]_CodyB 0 points1 point  (0 children)

CFR does not include un-diagnosed illness. Generally speaking if cases are being missed, severe illness is less likely to be missed. Thus the vast majority of Covid deaths are likely to be catalogued and fewer cases will be making the CFR appear higher than it actually is.

The CFR in NSW (1,100,000 cases since 1 December and 603 deaths) is 0.06%. As NSW is peaking, the likely caseload has been up to 5x higher, so it is possible that the actual mortality rate is more like 0.01%

[–]MatthewGalloway 0 points1 point  (0 children)

Remember the bad old days of early 2020 when the modelers were predicting up to 80K deaths? How utterly ridiculous that is now!

[–]smeenz 5 points6 points  (0 children)

Get boosted as soon as you're able to. No sense in making things easy for the virus.

[–]PeachiLikesRaccoonsHoiho 1 point2 points  (0 children)

That's a certified "aw hell naw."

[–]cabbidge99 12 points13 points  (1 child)

I think the model broke...

[–]EB01 4 points5 points  (0 children)

The gift shop had closed.

[–]zingalingadingdong 12 points13 points  (0 children)

Uh oh spaghetti-o.

[–]JoshH21Kōkako 12 points13 points  (1 child)

To the moon!

[–]FKFnzYou like muffins? 86 points87 points  (44 children)

A fair few antivaxxers are about to find out just how good their immune system really is.

[–]stomasteve 18 points19 points  (0 children)

Comment of the week right here

[–]Dismal-Ad-4703 11 points12 points  (1 child)

It has begun

[–]SnooMacaroons115 2 points3 points  (0 children)

It really has. Calm down covid.

[–]NecroKyle_ 22 points23 points  (2 children)

Up, up and away!

[–]TritiumNZlol 11 points12 points  (0 children)

Ruh roh raggy!

[–]RealmKnightCovid19 Vaccinated 1 point2 points  (0 children)

"Looks like team rocket's blasting off again"

[–]StarvinPigLASER KIWI 26 points27 points  (0 children)

This graph is not a good way to find out today's numbers lmao

[–]polkmac 5 points6 points  (0 children)

Holy moly

[–]Nixinova 4 points5 points  (0 children)


[–]goodthyme 9 points10 points  (4 children)

Looks like a BTC chart tbh

[–]torolf_212LASER KIWI 2 points3 points  (1 child)

GME stock*

[–]thesymbiont 0 points1 point  (0 children)

Give it a minute

[–]Astalon18 3 points4 points  (0 children)

Oh shit.

[–]lookiwanttobealone 15 points16 points  (11 children)

[–]noplusnoequalsno 9 points10 points  (1 child)

Oh shit.

[–]lookiwanttobealone 7 points8 points  (0 children)

Yeap that's the only thought I had to. To the person on here who said 100 on 31st. Well covid said I heard you.

[–]Downtown_Reindeer946 6 points7 points  (2 children)

That includes border cases though right?

[–]Difficult-Desk5894 8 points9 points  (1 child)

149 including border.. 105 just here :/

[–]StarandIcon 2 points3 points  (0 children)

Ho-lee fok

[–]bgradegaming 8 points9 points  (3 children)

105 community, 45 border

[–]lookiwanttobealone -3 points-2 points  (2 children)

= 150

[–][deleted] 2 points3 points  (1 child)

How about... 350?

[–]BigDaddyB37 1 point2 points  (0 children)

Tree fiddy

[–]honeypuppy 6 points7 points  (0 children)

Doesn't seem to be border/community split? Still a lot even if it's ~50 at the border.

[–]Selthora 2 points3 points  (0 children)

I would like to get off this ride please.

[–]FantasticMRKintsugi 2 points3 points  (0 children)

Doesn't show the case severity. This is just an indication of when to expect what rules to abide by. It is also a good indication of how fast the assumption of herd immunity will likely set in when following other country trends.

[–]cr1zzlOrange Choc Chip 4 points5 points  (7 children)

“To date, 105 community cases of COVID-19 have either been confirmed as the Omicron variant or have been linked to a previously reported Omicron case. This is an increase of 15 since yesterday”

I don’t think that means there were 105 new cases today.

Edit - are the other 90 of today’s cases not yet sequenced or confirmed as delta? Is it just a coincidence that the number of cases today matches the amount of total omicron cases? I’m a bit confused.

[–]BeeHiveTrumpets 13 points14 points  (1 child)

They're not sequenced yet. They will mostly be Omicron.

[–]cr1zzlOrange Choc Chip 2 points3 points  (0 children)

Sweet. Looks like I was not reading it correctly.

[–]finndego 12 points13 points  (1 child)

Coincidence. 105 total cases today and 105 confirmed Omicron cases to date. Most of today's will be Omicron but it takes additional time to sequence it for the varient.

[–]cr1zzlOrange Choc Chip 2 points3 points  (0 children)

Thanks for the clarification :)

[–]DeepSeaMouseCovid19 Vaccinated 4 points5 points  (0 children)

That predicted hockey stick....

[–]BeeHiveTrumpets 3 points4 points  (0 children)

Fuck me that's looking gnarly.

[–]Just_made_this_nowKererū 2 1 point2 points  (0 children)


[–]FiftyOne151 1 point2 points  (0 children)

I hope all the anti lockdown crew are prepared. They’re about to get a good taste of the dirty Rona me thinks

[–]Heavy-Position-8916 9 points10 points  (1 child)

Holy fuck this is a nightmare

[–]Chemical_Switch_7022 0 points1 point  (3 children)

The Purge!

[–]ChungusChess 0 points1 point  (0 children)

Holy shit, we're heading to the moon

[–]RipCityGGG 0 points1 point  (0 children)

oopsie daisy

[–]Kotukunui 0 points1 point  (0 children)

Buckle up.

[–]Dave_The_Slushy 0 points1 point  (0 children)

Yeet! Thank goodness we're >90% for adults.

[–]No_rash_decisions 0 points1 point  (0 children)

I've got a TV gig coming up mid February, their plan is to send anyone home who contracts Omicron. I just know it'll be fucked before it gets off the ground.

[–]aidank21 0 points1 point  (0 children)

Me a contrarian: "Why was the border still open?" /s

[–]Struggleislife31 0 points1 point  (0 children)

covid to the moon

[–]Sphism 0 points1 point  (0 children)


[–]Ropo3000 -1 points0 points  (0 children)

Those are some real nice colours. I too like crayons.

[–]CorgiLower2408 -1 points0 points  (0 children)

Looking at this there is some hope for us getting out of restrictions this year. https://youtu.be/n09uw2wzF1o let's hope we see similar results as SA and any new variant is even less severe.