Well if you want to "control public fear" for political and economic gain, you just adjust the CT value as required to bump up the positive rate or to lower it.

Note that the US CDC is using two different CT values: a higher one for unvaccinated and a lower one for vaccinated. That doesn't make any sense until you start thinking Hobbsian/Hegalian/Machiavellian.

If I was wanting to exploit the situation, this is exactly what I'd do. Instead I have ethics however.