Right now, that is true. That is why we are cancelling events here in 2020.
But that is not what I was asking. Continental asserted that something you said elsewhere is germane to this thread (or what Continental believes to be the "objective" of this thread, still unstated).
So far, this thread has been asking whether drum corps shows, or appearances of individual corps at such shows, have been impacted by disease concerns prior to 2020. So far, the answers show that individual corps have taken a sick day on occasion, and one corps had to take several such sick days in succession... but no entire events have been cancelled on that account.
Of course, no other drum corps seasons have had the kind of pandemic/quarantine situations that we face here in 2020. So if anyone thinks drum corps history holds some sort of profound relevance to the challenges it faces today, they will have to be specific.