Contact tracing works best as part of what experts sometimes call the Swiss cheese model, which involves layering multiple strategies. One method can have holes, but several combined can form a solid block.
Do it right, and “you could almost stop a pandemic in its tracks,” says Rajeev Venkayya, who was part of the US team that helped craft the George W. Bush administration’s plan to deal with the future. pandemics.
For covid, the appropriate layers would include comprehensive testing, effective contact tracing, and social distancing – but with few of those layers in place, the virus has gone wild. And once the spread is rampant, contact tracing is simply not enough.
The promise to come
Despite its shortcomings, digital contact tracing may still have a future. The arrival of several vaccines gives hope that the number of cases will drop to manageable levels. At this point, says Venkayya, “having all the tools we can at our disposal – including robust testing and tracing – will be really important. You’re just trying to keep pace and limit the damage. “
In the United States, as the Biden administration updates, federal or state solutions (like pushing for nationwide use of contact tracing apps) may be part of the answer. , as well as monitoring tools such as Bluetooth beacons, tracking bracelets, and QR codes that you scan to enter a cafe or workplace.
But the most important lessons from our global experience with exposure notifications may be less about the technology and more about how to implement it. The glitch deployment made it clear that introducing innovations – for this pandemic or the next – will require us to build trust, increase access and fairness, and consider the place of technology in complex systems.
Progress, of course, is about looking to the future. But as contact tracing reminds us, it’s just as important to retrace our steps.