Lady Deakin asked:
This is about identifying and isolating cases/exposed people after the fact, and the analogy with a vaccine (which is very different epidemiologically to contact tracing) didnt work for me. Vaccines work whether all cases are identified or not.
Yes, the name is more "marketing" orientated, to show the complementary nature to real vaccine, rather than it working like one. Although we can draw some parallels between them:
|Feature||Real Vaccine||Virtual Vaccine|
|During Vaccination||Injection into Body||Download onto Phone|
|After Vaccination||Body starts producing Antibodies||Phone starts logging Locations|
|The More The Better||Antibodies created||Locations logged|
As you pointed out, the big difference is that real vaccine works even if not all cases are identified, while virtual vaccine goes the opposite way, it job is to identify all cases so the virus cannot spread in the first place.
A more comprehensive real vaccine vs virtual vaccine comparison table is at the bottom of this page: