alt Hacker NewsYou can't design an infectious pathogen without testing it.
It's got all the same problems as the concept of a dirty bomb did, only worse (dirty bombs aren't practical because handling highly radioactive materials en masse is both highly visible and will kill anyone trying to do it without the money and facilities).
If the goal is just destruction then letting it free in random public places is not that hard. Especially in countries where wearing a mask is not frowned upon.