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NZ COVID Tracer v3 will have the Apple/Google Exposure Notification Framework! It's called Bluetooth Tracing, and is another layer of defence in protecting ourselves from COVID-19. Best of all, once you turn it on, you don't have to do anything else! https://www.newsroom.co.nz/covid-19/bluetooth-contact-tracing-beefs-up-govt-app
NZCTv3 should be available from December 10 onwards - most phones will update the app automatically, but you may need to update manually in the play/app store. Importantly, if you want to use Bluetooth Tracing, you need go into the app and opt-in to turn it on.
A/G Exposure Notification has now been implemented in over 25 countries around the world, so we have had the benefit of seeing how it has been used elsewhere and learning from their experiences (and in some cases, learning from their code too).
Bluetooth Tracing works with smartphones exchanging Bluetooth signals with each other to indicate that they were close to each other. Since Bluetooth signals are relatively short-range, this limits how far apart the phones can be when exchanging signals.
The phones measure how long they are physically proximate for, and give an approximate sense of distance based on the strength of the signal. Most importantly, the phones do this exchange anonymously - they do not reveal who owns the phone, with new random ID numbers each day.
All checks for potential overlaps and exposures are done on the phone itself - the Ministry of Health do not get access to your data. Apple and Google do not get access to your data either, and have set strict rules to say the data can only be used for public health purposes.
Because of this design, Bluetooth Tracing does not and cannot replace manual contact tracing, but it can be a helpful tool in speeding up the process. If you have been infected with COVID-19 but don't know it yet, then contact tracing will help cut the chain of transmission.
Once Bluetooth Tracing is turned on in the app, it will stay on until it is turned off. No further action from the user is needed. Bluetooth Tracing itself does not use any data, although you may need data or WiFi to download the app, and to check the list of ID numbers from MOH.
It is still important that we keep personal diaries of where we have been to help contact tracers - one way to do this is through scanning QR codes, but other methods like taking photos of where you have been, using Google Timeline, or a pen-and-paper diary are also helpful.
It is still mandatory for businesses to display NZ COVID Tracer QR codes, because it is still a good way for people to keep track of where they have been, and the exposure notifications that come from the QR-code based system will still be used where needed.
For people without smartphones, or with older smartphones, unfortunately they can't use Bluetooth Tracing yet. I hope the govt will look at further options like vouchers for smartphones or wearable devices that enable every NZer who wants to participate to be part of the network.
Importantly, the code for NZ COVID Tracer has also been made open source. Anyone can inspect the code on Github and check that it does what the government says it does. I invite anyone who is inspecting the code to get in touch and compare notes.
Bluetooth Tracing is only useful if enough people have phones with it switched on - it needs enough people participating in the system to cover a sufficient proportion of interactions. I think we want to be aiming for at least 60% of the adult population using Bluetooth Tracing.
COVID-19 is still very real and serious in many places around the world, so an additional layer of defence that is quick and easy to implement is helpful. If you can use it, and feel comfortable about it, I encourage you to use Bluetooth Tracing in the NZ COVID Tracer app.
And the most surprising thing to me - I wrote about the Apple/Google framework back in early April (!!) and somehow most of the article is still valid and applicable today: https://informedfutures.org/digital-giants-enter-digital-contact-tracing/. This is a big step for the NZ response, spread the word!
And for anyone wondering about this, MOH calling it "Bluetooth Tracing" is a very deliberate decision - trying to distinguish it from "tracking" (even though only one letter is different) because there's no location data and people seem less paranoid about tracing than tracking.
That's basically me saying "please use the word tracing and not tracking".
For those following in close detail, the NZ implementation uses iOS v1 and Android v1.5 of ENF, not the newest version that has "exposure windows". Details on scoring calcs here: https://github.com/minhealthnz/nzcovidtracer-docs/blob/main/docs/exposure-notifications/scoring.md
For those following in close detail, the NZ implementation uses iOS v1 and Android v1.5 of ENF, not the newest version that has "exposure windows". Details on scoring calcs here: https://github.com/minhealthnz/nzcovidtracer-docs/blob/main/docs/exposure-notifications/scoring.md
More official information about Bluetooth Tracing here: https://covid19.govt.nz/health-and-wellbeing/protect-yourself-and-others/keep-track-of-where-youve-been/nz-covid-tracer-app/
and really, really importantly, a delightful video from MOH on Bluetooth Tracing about how it works including the "digital high five":
And full comments from me (many overlapping with this tweet thread) alongside other experts via the Science Media Centre this morning: https://www.sciencemediacentre.co.nz/2020/12/09/bluetooth-comes-to-covid-tracer-app-expert-reaction/
