In the wake of the re-emergence of community transmission of COVID-19 in New Zealand, Dr Andrew Chen has been providing expert commentary in relation to contact tracing and other related issues.
A contact tracing wake-up call: A contribution to the Science Media Centre
The announcement of four new cases in the community is a timely reminder that we all need to be engaged with contact tracing processes. We don’t need to panic, but it reiterates the message that Covid-19 can reappear and we will need to continue to maintain and collect contact tracing records for awhile. This means keeping good records of who we have been in close contact with, and where we don’t know who the people around us are, keeping records of where we have been at what times. When new cases appear in the community, contact tracers will want at least two weeks worth of records to help them identify who else may have been exposed to the virus.
There are a number of tools that you can use to help collect and record this information. The most important is the government’s NZ Covid Tracer app, which can help you keep logs of your movements by allowing you to scan QR codes for businesses. Registering for the app provides the Ministry of Health with up-to-date contact details in case they need to call you, which is already helpful in itself. Importantly, the app can also be used to help notify you if your logs indicate that you have been in the same place at the same time as someone infected with Covid-19 (through an exposure notification mechanism). The app helps contact tracers notify people more quickly, which can help reduce the spread of the disease if people then isolate or get tested more quickly too. This may be especially important in cases where there may be a lot of possible contacts, and the manual approach of calling each person may take too long. The app now also has a manual entry functionality that allows users to enter records for places that do not have QR codes available. Based on the design of the app and the rules governing how the data is handled, the privacy risk is very low and it should be safe to use.
If you cannot or do not want to use the NZ Covid Tracer app, there are other digital tools that can be helpful, such as turning on Google Maps Timeline on Android smartphones, using other QR code or location tracking apps like Rippl, or taking photos of the buildings that you enter (which will automatically have a timestamp associated with it). A pen and paper diary method is also fine for keeping your own records. These are still valuable in the event that you are diagnosed with COVID-19 and need to provide information on your close contacts to a contact tracer. However, it is important to note that these methods will not allow the Ministry of Health to automatically inform you about exposure risks relevant to you.
This is also a timely reminder that businesses should display the NZ Covid Tracer QR code, so that their customers and visitors can easily add to their records. This is an important part of protecting both your customers as well as your employees, so that they can be identified and notified quickly in the event that there is an exposure risk.
Conflict of interest statement: I have met with the Ministry of Health and provided some advice, but have no financial relationship.
While there are other technologies available, such as Bluetooth-based methods like those we have seen overseas, it is important that we focus on the tools that are available to us right now.
Manual contact tracing (i.e. public health officials interviewing active cases and making phone calls to contacts) is still the primary mechanism through which we are conducting contact tracing.
The NZ COVID Tracer app is a useful tool to provide a bit more information to contact tracers, and importantly can help notify you if they identify an exposure risk and there is an overlap with your location logs.
Keeping your own records through other means is also helpful, and it is worth spending the time to retrace your steps over the last two weeks, just in case it is needed by contact tracers.
Bluetooth-based methods (including the Apple/Google protocol and CovidCard) are being actively investigated and developed by the government, but I expect that this will still take a few months to be rolled out and we should not rush this process – it is more important to get it right.
These other technologies are not silver bullets and we have seen limited effectiveness overseas, so we need to think of these technologies as augmentations/support for the manual contact tracing system.
Under the recently released COVID-19 Public Health Response (Alert Levels 3 and 2) Order 2020, s16(2)(d) requires that businesses at level 2 (and level 3) must ‘display a copy of the QR code for the business or service in a prominent place at or near the main entrances to the workplace’ from noon next Wednesday, where the ‘QR Code’ is defined earlier as ‘a unique identifying code issued by the Government for the purpose of supporting contact tracing’.
I expect that this refers to the NZ COVID Tracer QR codes – increasing the availability and visibility of these posters will hopefully improve use of the app and help people keep records of their movements more easily. We have previously seen that more businesses making QR codes available leads to a corresponding increase in participation, so I hope that this new requirement will lift the participation rate.
Businesses can easily generate a QR code through the Ministry of Health using a self-service form.