There are all sorts of problems with government tracing, first and foremost that it’s another huge step towards the total surveillance state. From James Ketler at mises.org:
As states move through phases of reopening, “contact tracing” has remained a topic of national interest. For months now, talking heads in the government and media have hailed the strategy as the country’s saving grace. One NBC headline read, “Coronavirus contact tracing could stop COVID-19 and reopen America,” and a CNN article declared, “the US — or really any country — can’t safely reopen without significant amounts of contact tracing and testing.” With this starry-eyed perception, dozens of states have rushed to train and hire tens of thousands of contact tracers—what former CDC director Tom Frieden gleefully described as an “army” of tracers.
It’s true that contact tracing has been an indispensable asset many times in the past, helping to snuff out viruses by diligently tracking their spread. So it’s no mystery why some health experts are flocking to it in the current crisis.
In short, this is how it works: contact tracers conduct short, over-the-phone interviews of newly diagnosed patients about who they have recently been in close physical contact with. The fear is that these recent contacts may have contracted the virus from the patient before he was diagnosed. These contacts are then phoned by tracers, informing them of this risk and encouraging them to seek testing and self-quarantine immediately. Tracers continue this process on down the line with the aim of reducing the instances in which the virus is transmitted.