Respuesta :

Well, back in their day the doctors where probably prescribing vaccines that the scientists of today don't believe are needed, or can actually harm you instead of help you. It's just considered outdated right now, because we have better more effective vaccines.
Hope that helps! :)
macipope
Today's time is different than theirs because a lot has changed and more discoveries have been made , so we don't need certain ones they may have needed then . Hope this helps !