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Covid-19 contact tracing


Everybody is now an expert epidemiologist, including me.

While I applaud the New Zealand government for its effectiveness in keeping the country safe and for having successfully stamped out the epidemic the first time around, I am a bit frustrated that no effective contact tracing system has since been put in place and that we have to endure lockdown again. We enjoyed 3 months of freedom, semi normality and a mini boom, but we knew that another outbreak would occur. It never was a matter of if, but a matter of when. I was hoping that when it would happen, we would have the capabilities to keep the lid on it quickly and efficiently. Reality proved me wrong.


The existing New Zealand tracing system is an App which relies on the public scanning QR codes that must be printed and displayed by all business and public places. It is too cumbersome to be widely used and is only a very incomplete record of our movements anyway. A paper trail as a backup is excruciatingly slow and error prone.

Yet, we do know that, along with wearing a mask, testing, tracing and isolation are our best tools to manage the pandemic until either the virus loses ground (which could be years away, or much sooner but while we can hope for the best, we have to prepare for the worst.) or until we have an effective, cheap and safe vaccine. (which could also be years away.), vaccines that the anti vax would somehow have to accept. (which could be never.)


If done correctly, testing, tracing and isolating would remove the need to confine entire populations and to ravage economies. We did not know any better back in March and April, but we do now. We have effective testing capabilities, effective isolation facilities, effective border control systems and a government that communicates very well, but we have a completely useless contact tracing system…the missing weapon in the arsenal. We don’t know who to isolate and who to test…or far too late. Why?


What frustrates me is that we already have the infrastructure and technology to track and trace, quickly, cheaply and effectively. We are simply not taking advantage of it. The vast majority of the population has a smartphone of sorts (Over 4.5 million in NZ population of 5 million.) and the vast majority of these devices know where they are, at all times, with pinpoint accuracy… and can record this information. Do you follow my drift thus far? Do you really need to read the rest of my mansplaining lecture or have you already worked it out by yourself?


GPS (Global Positioning Systems) navigation tools such as Google Map or Waze do it, have been doing it for over 10 years. These navigation tools are also capable of uploading these movements as they occur, very small data packets, not a huge load on the network,  so that their algorithms can warn us in advance of traffic congestion ahead and suggest alternative routes, adjust our estimated time of arrival, share our travel progress with a third party of our choice. We happily take advantage of these very convenient tools.

In other words, we have existing infrastructure and technology capable of knowing where a phone has been within 10cm,every second, to record that information and to upload it to a server. There is no need to reinvent the wheel and to develop expensive infrastructure, it is already there and readily available. This is trusted and tested technology, not a dream in the sky. It works on 3G, 4G and wifi, reliably, thus covering all the major population centres, at all time, with no effort of our own. It has practically become a natural order of things. Even your crapy old phone with a cracked screen held together with a bit of tape is perfectly capable of it. If you have never used a navigation App, please know that millions are, daily. Millions of people are even buying smartwatch gadgets with the express purpose to track and share their movements, along with their heartbeat and pace count. There are Apps allowing you to retrace your path, and find your way back home if lost, like Tom Thumb’s pebbles. This is no rocket science.


It should be fairly easy to leverage this proven technology to develop an App that would automatically capture and upload a device’s movement on a centralised database where it would be kept for 2 weeks, the maximum infection period of most viruses, including Covid-19. Tracing then becomes a matter of a simple query to the database. Phone subscribers who have been in contact within a certain radius, within 14 days, at the same time and for a long enough period of time to another phone number that happens to belong to a new positive case can be instantly notified via SMS and asked to self-isolate and to get tested.
The last cluster could have been identified and traced in a matter of minutes, instead we still don’t have a clue 10 days later, despite having teams of expert’s tracers working around the clock, doing their pathetic best, using the data from public transport cards, shop receipts and other ad hoc information to slowly put the puzzle together while unaware cases are blissfully transmitting around and Auckland is being confined, again. Simply not good enough.

Other than installing and activating an App, a 2 minutes job, the public would  not have to do anything. The App works silently in the background, as long as your phone is switched on and with you. The government could impose on phone companies not to charge their subscribers for this data traffic. This is technically possible. Even without credit or without a plan, your phone can still call emergency services.


Assuming that 4 million people have the App activated and have their phone switched on 15 hours per day, that the App records locations every 5 minutes and that the data is kept for 14 days, the database will have a maximum of 10 billions rows keeping a phone number (or some other identifiers such as the device IMEI, a 15 digits unique number), a latitude, a longitude and a time stamp. A simple SQL query can quickly find out which phone numbers have been within 2 square metres for more than 5 minutes from another phone number and send an SMS to these phone numbers:
The national tracing App has detected that you may have been in close contact with a positive COVID-19 case on (insert date and time) at or near (insert street address and/or Google place ) (on level X)  We recommend that you self-isolate and get tested as soon as possible. Please contact the Ministry of Health on www.mmmmmm.co.nz or 0800 xxxxxxx for more information. We may attempt to contact you in the near future. This message reference number is 64763489939. Be safe, be kind.“


If the same phone number has been in contact more than once, a single SMS is sent but back office contact tracers have access to this information to prioritise their follow up actions. If hunting a source case is necessary, second and third level contacts can also be queried. There is after all an average of 6 degrees of separation between two random individuals, according to some urban legend.


It seems so simple.
Surely others than me have also seen this possibility already… Why is this not happening? (It is in South Korea I believe.)   I am no network engineer and no database expert, and I may have completely missed some major technical obstacle to the implementation of such an App. If you have any tech creds, please prove me wrong.


I am no epidemiologist either and I may have also completely misunderstood the purpose and mechanics of contact tracing. Please do not hesitate to educate me, because journalists are not. For now, I hold the belief that health authorities instantly knowing who a new case has been in close contact with, when, where and for how long in the last 2 weeks and instantly knowing how to contact these people can only be a good thing, even the entire and only thing.


Option B.
Now, smartphones are also capable of knowing what other phones are nearby, via the Bluetooth capability. It should be possible to enhance this technology to record on the device the phone number, locations, and time stamps of contact with nearby devices, silently and seamlessly.

If someone is then diagnosed positive, they can mark themselves as such and the system would alert these phone numbers with an automatic SMS. The advantage of this solution is that there is no need to upload anything on a centralised database, thus, perhaps, alleviating privacy concerns. The list of contact would only be uploaded to the health officials and tracers to examine if and when you are diagnosed positive.  There would be a need to implement a mechanism that would prevent people to self-diagnose themselves and unnecessarily alert their Bluetooth contacts. Perhaps only a doctor could provide users with a code allowing to mark themselves as positive.
This can be an App or even integrated in the operating system and automatically installed on your device at the next update.


Technophobia and Privacy Concerns.

There is of course always some push back from the technophobes. Most people mistrust something they do not fully understand as ignorance generates fear. But mostly I blame it on Aldous Huxley and the Facebook conspiracy theorists.

The main obstacle I think is political. Governments do not want to offend these electors who have been brainwashed by successive scifi novelists and prophets of doom into having privacy concerns and are afraid of a brave new world where the database knows that they spend two hours in a motel room with another phone’s subscriber that is not their legit spouse. Opposition parties would accuse the party in power of wanting to be big brother, Judith Trump would seize the opportunity to lash out with exaggerated and hurtful adjectives in order to look strong, unlike these “be kind” snowflakes.  As a result, we let the epidemic send people to hospitals where some will die, businesses and services to close and the population be confined for extended periods of times. FFFFFAAAaaaaa…


Is there a danger that this information is misused for malicious intent or commercial spying? No more than IRD knowing exactly who you are, where you live, what you do and how much you earn, no more than your bank knowing how much you paid for that motel room on that day and time, no more than your Internet provider knowing how many hours of each day you spend watching porn. No more than your Health District Board knowing what disease you have, what drugs you are taking, what your blood pressure is and whether or not you have been vaccinated, when, for what, how much you weight and the graph of your cholesterol levels. No more than Google knowing that you have been searching for a recipe for Thai chicken and then serving you ads for a holiday in Thailand, Knowing where you are in order to give you personally adapted search results Or your local mechanics knowing when your WOF is due and how to contact you to let you know to book your car in. No more than your navigator knowing where you are, now and where you have been in the past.


Is there a danger that if we let government do this it would set a precedent, create a new normal where constant general surveillance is the norm? Yes, Indeed, this could happen, as it did with public and private CCTV cameras that are now recording and storing evidence of our every moves. Is there a danger that this info is leaked? Yes, indeed. The question should be “Are the benefits greater than the risks?”  And  “Is your personal right to privacy more important that everybody else right to be free and healthy?”


If your privacy is a concern, cancel your bank account, your internet, your phone, stop working, applying for social security assistance, applying for credit, for a passport, stop travelling, buying anything, never use public transport nor rent a car, never subscribe to an insurance, bury your cash under a lemon tree, talk to no one, never visit a doctor or hospital and most importantly wear a mask at all times because you are almost always on camera. “They” are watching you and “they” are going to get you.


Without being paranoid, I still do not like the idea of being spied on without my consent any more than anybody else, but in this case, it would be voluntary, and I am convinced that there will be plenty enough of sensible and reasonable people activating the App for it to be a very effective contact tracing tool for the common good. For the rest, it is just a matter of education and communication and the App would eventually be accepted in trust as a natural order of things. Besides, New Zealand already has privacy watchdogs in place and Ombdusmen, to ensure that data collected by the government and its agencies does not breach the Privacy act.


The Odd Idiot.

There will always be the odd idiot, no system or regulation can prevent that. There will always be the odd idiot no matter what. And of course, no amount of communication and reasonable explaining will ever convince the one idiot, they never change their mind.  I can only resort to calling them dicks. If they call me a cunt in return, I will be flattered. Apparently, we are what we eat, according to some other urban legend.


Olivier Duhamel


If you wish to react : olivieroduhamel@gmail.com


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