User blog comment:FairyRaven/Fairy Tail Chapter 470: Hybrid Theory, Review and Commentary/@comment-5303512-20160125131054/@comment-9595671-20160125185153

Plus recall what Zeref said when we first met him? He doesn't try to talk to humans because it's the equivalent to us ignoring a bug.

Essentially, Acnologia swatted him away like he was a fly annoying him. The main difference from usually is that he didn't do it as a Dragon.