One of the things that used to fascinate me early on in the pandemic was how officials could track down how someone contracted the virus, and create a chain of transmission events, literally like an infection network. Admittedly there is uncertainty in this model and events are probabilistic rather than certain, but it certainly was amazing that even a hazy picture of viral transmission could emerge. Isolation of exposed people seemed to be the obvious purpose, but I believe that focusing on only this purpose has unfortunately led us to where we are today, with contact tracing relegated because it is no longer feasible to isolate every exposed person. A very important externality of contact tracing has become unavailable to us as a result.
Individual decisions are hard even in normal times. During a pandemic, they become stressful. The best recourse is to deploy our collective understanding to aid people making choices everyday, and in turn using those decisions to inform and update our understanding. But without contact tracing, it is no longer easily identifiable where the virus spreads most efficiently. Two years into the pandemic, I still cannot claim with confidence whether taking well-ventilated and mostly mask-compliant public transport is as good (or better) than taking a cab. I cannot tell whether attending fully masked classrooms and seminars is as safe as being virtual. If we’d kept track during each wave where the virus seemed to be spreading the most, these would have been easy questions to answer with the data. Like most failures, this has been a failure of imagination by those entrusted with our collective decision rights.