I am, and have been for years, a confirmed anti-vaccinationist...I have not the least doubt in my mind that vaccination is a filthy process that is harmful in the end.
In the dictionary of the seeker of truth there is no such thing as being "not successful." He is or should be an irrepressible optimist because of his immovable faith in the ultimate victory of Truth, which is God.
Do not believe in telling people of one's faith, especially with a view to conversion. Faith must be lived, and when it is, it becomes self-propagating