While you're correct to point that out, I'm not aware of any health experts who expect that the current crop of vaccine candidates are sufficient to stop the disease from spreading. The hope is that it will spread slower and/or be less severe.
I'm definitely no expert on this, but it seems a little early to say. There's 321 candidates in development (albeit some very early stage) and none have fully passed trials yet. I think the effiacy of various candidates isn't clear yet (i may be totally wrong)
